How to Prevent & Treat Colds & Flu

Welcome to the Huberman Lab podcast where we discuss science and science-based tools for everyday life. I'm Andrew Huberman and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today we will talk about

colds

and flu. We'll talk about what. what a cold really is and what a flu really is in terms of how it affects your brain and your body and of course we'll discuss how to avoid getting

colds

and flu. In fact, there are some great science-backed techniques to avoid getting colds and flu, but of course. It's impossible to completely avoid getting a colder flu in your life, so we also looked at how to get over a colder flu more quickly if you do get one, so during today's discussion I'm going to talk about the immune system that I'm going to give you. some mechanistic understanding of how your immune system works and I promise to make that discussion accessible to everyone, regardless of whether or not they have a biology background and with that understanding of how your immune system works you will be in a much better position to understand what tools, That is, what protocols to implement in case you are exposed to a colder flu or if you are trying to get over a cold or flu faster than you otherwise would, you will learn about some powerful behavioral tools to boost your immune system and We will also discuss several compounds you might consider taking to improve the function of your immune system to protect yourself or

treat

colds and flu.

I will also dispel a number of common myths about

treat

ments for the common cold and flu. Oh, there are so many ideas about what one could take or do to avoid getting the coldest flu or get quicker relief from a colder flu. However, many of them are pure myths, it just doesn't make sense to support them and in fact there is some science that counters those ideas, but the good news is that there are in fact science-backed behavioral protocols and compounds that They could be considered to

prevent

and treat colds and flu before starting. I would like to emphasize that this podcast is separate from my teaching and research. roles at Stanford, however, is part of my desire and effort to provide consumer information about science and science-related tools at no cost to the general public consistent with that topic.

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No, unfortunately, I can't tell you the cure for the common cold today because, in fact, there is one. However, an interesting question is why we don't have a cure for the common cold and the reason is that the cold virus, as it is known, is actually a group of different viruses. Some colds are caused by one called a serotype of the virus. Other colds are caused by a different serotype of the virus. There are more than 160 different types of what people call cold viruses. Now cold viruses fall under a general category of viruses called Rhino viruses.

You can remember it easily because Rhino sounds like Rhino. horn the rhino horn which of course is in the center of the rhino's face, which is where its nose is and the cold almost always causes some degree of nasal symptoms in humans, whether it's a runny nose, sneezing or a stuffy nose. or sometimes, unfortunately, now all three. The reason we don't have a cure for the common cold is that all those different serotypes of the cold virus mean that the virus itself has a different shape on the outside and, as a result, even if you've been exposed to a cold. and you have developed antibodies against that cold virus, the next cold that appears will probably have a different form and therefore your body's antibodies against the cold virus that you successfully combed before cannot attach and defeat the next serotype different from the cold virus.

Now, a little later, I'll talk about the immune system and how those different antibodies are generated, but for now, understanding that there are many different types of cold viruses explains why we don't have a cure for the common cold in the first place. , but also why you can get several colds in a given year or even a given season, because even if you develop antibodies against one serotype of the cold virus, a different serotype can appear and you can get sick again with that new serotype of the virus of the cold, so how do you get a cold now?

One of the problems with the cold virus being called a cold virus and the fact that there are in fact more cold viruses present and transmitted between humans in the cold winter months of the year is that people Generally, It assumes that it's the cold temperatures outside that really give you the cold virus and that's simply not true; However, what you heard when you were a child most likely was your mom, but maybe your dad told you, "don't go out without a sweater or jacket." in you are going to catch a cold or you are going to catch a cold you know that this myth has been put to rest that cold temperatures in themselves are the cause of contracting a cold virus and that is simply not true, the virus that we call a cold The virus is transmitted by breathing or by sneezing or when people sneeze or cough or breathe into their hands and then touch surfaces and then other people touch those surfaces and then probably touch their eyes to become self-infected.

Now let's get into the details of how far the virus can spread with a sneeze, how long it can survive on your hands, etc., but for now know that the cold virus is a fairly stable virus in the sense that can survive on human or non-human surfaces, i.e. skin. or on a table or in a glass or on a door handle for up to 24 hours, so for all you hypochondriacs, I probably just gave you a little boost in cortisol and for you non-hypochondriacs, I hope what I just told you to point out the fact that simply avoiding people who sneeze and cough is not enough to avoid colds and flu.

However, just because a cold virus is alive and healthy on a certain surface, say on a door handle, does not mean that if you touch that door you will necessarily be infected with that cold virus and that will be Because your skin actually provides an excellent barrier against most viruses and bacteria. Your skin also includes a lot of antiviral substances, even if you haven't put any of that, you know, alcohol. Things or hand sanitizer on your skin is a very important barrier component of your immune system, we'll talk about that a little bit later, but if someone has a cold and maybe you know they're wiping their nose or sneezing. a tissue, hopefully, into a tissue and then discard that tissue, cold virus particles are extremely small, how small, most of us are familiar with thinking in centimeters or inches, if you think that a millimeter is 1/ 100 of a cmet, you can take a millimeter and you can divide it into a bunch of little slices as well so that you get the micron, the micron is 11,000 of a centimeter and if you want to get an idea of ​​how thick or thin the side of a card is The small, thin side of a credit card is about 200 microns thick, so if you place your credit card on a table and then look at it from the side, that tiny, thin edge of about 200 microns is formed by the cold virus. particles that are probably in the range of about five microns, so extremely small.

I'm talking about the cold virus, so with a good sneeze or even a light sneeze it can spread very far. The good news is that those particles are relatively heavy, they don't. they tend to fog up in the air for a long time, they tend to fall to the ground or surfaces, but as I mentioned before, they can survive for a long time on those surfaces, so if you touch your hand to a door handle, a table or shaking hands with someone who has the cold virus on their hands, either because they themselves have a cold or because they came into contact with someone who had the cold virus and it somehow landed on their hands simply when the other person sneezes .

All of these scenarios are very realistic that the cold virus will go away. It won't infect you unless it can get into your body and one of the main entry points for it to get into your body is through your eyes, clearing that cold virus in your eyes. Now you may think okay, I'm just not going to touch my eyes. eyes, but a little later we'll talk about a study that shows that almost always, in fact, almost always, when you meet someone new, you touch your eyes and how often people touch their face, which is the region of the face around the eyes. and his eyes throughout the day are extremely high, so this is one of themain routes by which the cold virus is transmitted from one person to another, but of course there is also the route that we are all familiar with, which is the person who is sneezing or coughing or blowing their nose into tissues and then throwing them in the trash and not washing your hands every time you do, so an important aspect of today's discussion that we'll get into once.

I also present to you what flu What is it and how is it different from a cold is that we are going to need to talk about at what stage of infection people are actually contagious with the coldest flu and there is actually a lot of mythology about this, in fact, there is many lies about this. people cough or sneeze and they say oh yeah I'm not contagious anymore or people make up these things like oh you know if you had the flu for 2 days then you're no longer contagious or you can do it. Don't be contagious until you have symptoms, so we'll go over all aspects of contagion and how coughing or sneezing or how long you've had a cold or flu actually relates to whether or not you're contagious at a time. but for now know that the cold virus is very, very small, it can be transmitted through the air, it can be transmitted by skin-to-skin contact, and it can survive on surfaces for up to 24 hours and when those surfaces are touched. o A person with the cold virus often the way it will enter your body and infect you so that you get a cold is by touching the region of your eyes, although touching other regions of your body can also transmit the cold virus to you, for example.

For example, the mouth and lips, but that's actually much less common, so we'll talk about that in a moment. Different serotypes, that is, different types of cold viruses, tend to create a different range of overall symptoms, so you know a cold could actually be a quote-unquote bad cold others are milder some tend to cause more discharge nasal others plus nasal congestion and a little fever or in some cases a lot of fever one thing that is important to understand is that if people are going to be infected by the cold virus they tend to develop symptoms a day or two after being exposed to the cold virus. virus.

Now the good news is that if you are exposed to the cold virus, that doesn't necessarily mean that you are going to get the cold virus, that is, if your immune system can fight off that cold even if you have never been exposed to that serotype before, then you won't actually get that cold and you won't spread it, put another way, it is possible to avoid getting the cold virus even if you have never been exposed to that cold virus serotype and come into contact with someone who has that virus serotype of the cold or touching the surface of an object, door handle, etc., that has a particular serotype of the cold virus. and God forbid you then wipe your eyes, that doesn't necessarily mean you're going to get sick and a good portion of today's episode will focus on science-backed tools that allow you to boost your immune system and greatly increase the likelihood of that even if you are exposed to a new serotype of the cold virus that is new to you and that your body has never seen before, you will not get sick, another thing you should understand about the cold virus is that you are usually more contagious to other people when you feel at your worst, that is, when you are coughing and sneezing and have a stuffy head, watery eyes, etc., but you can also be contagious to other people when you start to feel better. said that most of the data points to the fact that about 5 to 6 days after reaching the peak of the worst symptoms or I guess we should say Nader is the decline of the worst symptoms because it is such a terrible state where you probably Is coming out of the phase where you are contagious now?

I want to be very clear that that does not mean that if you have had a cold for five or six days you are no longer contagious if you continue to sneeze and cough from watery eyes at night. you feel much worse first thing in the morning you feel especially groggy Etc. well, then you're still contagious another way to frame this is that you know those people who keep showing up at the gym and at work and say yes, i have this cold but I've had it for a few days now I'm no longer contagious and they wipe their eyes and blow their nose, frankly, they don't know what they're talking about. basically walking, talking, breathing, sneezing, coughing, a cold virus.

Vector, a vector is a route for the passage of a virus, so please, if you are sneezing, if you are coughing, if you are still experiencing symptoms of a cold, stay home, stay away from other people as much as possible. possible and I realize that some people just can't avoid going to work or can't avoid interacting with other family members or other people if they have the cold virus, but this mythology that if we've had a cold for a few days and we are starting to feel better but we still have symptoms that we are not contagious, that is pure myth, it is simply unfounded, in fact, now there is nothing that can be done about that first day or two after which we are exposed to a cold virus where we are not experiencing symptoms and it is very possible to transmit the cold virus to other people, but I think that all workplaces, all home environments, all gyms and all societies would benefit greatly if people people sick with a cold would not expose other people to it. cold virus as much as possible and in fact this is a serious problem, it's not just about a few colds and watery eyes, there is a huge financial, mental health and physical health cost for people who catch colds and It's not just people with compromised immune systems. or older people, what we generally refer to today as a cold, it can be mild, it can be moderate, it can also be very severe and it can exacerbate other health problems that people have and we'll talk about that a little bit later and how to offset some of those health issues, okay, now let's talk about the flu virus.

The flu virus is, as I mentioned, a virus and just like with the cold, there are different serotypes of the flu virus, there are also different general categories of flu viruses, so I have type flu viruses. A, influenza type B viruses and influenza type C viruses and, by the way, I am saying influenza viruses, but of course I mean the flu, but nowadays it is commonplace to refer to influenza as Flu Similar to cold viruses, different types of flu viruses exist based on the different types of proteins they express on their surface; In fact, in the news in recent years there have been several different strains of flu viruses that have been described according to the characteristics of their surface proteins things like the H1N1 virus what is H1N1 H1N1 describes the different types of proteins that are expressed on the surface of that particular flu virus now the most common type of flu virus is found in that flu category this is the type of flu that caused the Spanish flu, now the Spanish flu , which by the way did not originate in Spain, people believe it probably originated in New York or perhaps somewhere else, but certainly not in Spain, killed between 17 and 50 million people, depending on what literature you read is a number huge number of people and occurred in four different waves of infection that occurred between the years 1918 and 1920 the Spanish flu was a type A H1N1 virus and in fact it is worth noting that this winter season there have been some cases of H1N1 already reported in the United States and elsewhere now, of course, the goal is always to contain the spread of those flu viruses and that is achieved through several different approaches, the best and most reliable, of course, is not to come into contact with someone who is a carrier of H1N1 or any other type of flu virus, however, depending on the way the flu virus infects the body, the way symptoms arise, and the ways the viruses spread , that can't always be avoided, one thing I should know and I consider that a fortunate aspect of flu virus biology is that the flu virus, unlike the cold virus, can only exist on surfaces for about 2 hours, after about 2 hours it tends to die, so the flu virus is usually transmitted by human contact or coming into contact is walking into a cloud of someone's sneeze that contains the flu virus or cough of someone that contains the flu virus and yes, it is possible that shaking someone's hand can introduce the flu virus to your hand and then if you wipe your eyes or I'll talk about some other portals of entry for the flu virus and cold virus in a few minutes can enter your body and infect you and yet you can get the flu virus from surfaces;

However, that is much less common than the flu virus passing through. By human contact there are now not as many different types of flu viruses as there are types of cold viruses and that is why there have been attempts to make flu vaccines or so-called flu vaccines. I think most people are familiar with the signs and advertisements online, in the workplace, and at school that say you know to get a flu shot this season. The reason flu vaccines can exist is because there are enough types of flu viruses present in a given year that specific vaccines can be given. generated against that particular strain of flu virus, so how effective is the flu vaccine?

I want to be very specific here when we say that the flu vaccine in the singular implies that there is one flu vaccine that can fight all the different types of flu and As you just learned, that is not the case, so we should probably say flu vaccines, but just for simplicity, when I say flu vaccine I mean the flu vaccine that is given in a given flu season and that targets specific strains of flu. flu because researchers have determined that that particular flu strain or strains are the most abundant in that particular flu season. Studies have shown that getting a flu vaccine reduces the risk of contracting the particular flu that is most prevalent that season. around 40 to 60% but of course the flu vaccine is completely ineffective at fighting any other form of the flu virus and of course colds or other types of upper respiratory infections.

Studies have also shown that getting a flu vaccine can reduce the severity of symptoms. If they get the flu anyway, personally, I usually don't get the flu vaccine and the reason is that I don't tend to go to environments where I'm particularly susceptible to getting the flu that I don't work in. in a hospital or clinic. I don't usually interact with a large number of people on a daily basis so I have chosen not to get the flu vaccine now, that doesn't mean I never got the flu as I mentioned. I used to tend to get sick with a cold or flu about once every 18 to 24 months and the severity of that cold or flu has ranged from, at one point, a very high fever in one case, but usually a moderate fever and the symptoms usual. of malaise that we have been discussing and I have managed to overcome them without having taken the flu tent quite easily now, of course, we also do not know if they were actually flu despite the clear differences between cold and flu symptoms. most people don't really know if they have a cold or flu, so this is another thing to think about when considering whether or not to get a flu shot, because at least as far as I know, most workplaces They do not require people to get vaccinated. flu shot I could be wrong about certain workplaces, but my experience is that most workplaces do not require people to get a flu shot when you get a flu shot, you are really hedging a bet, you're hedging a bet against the fact that it will. whether or not you are exposed to that particular strain of flu virus that is most abundant in that season or to the strains of flu virus that are most abundant in that season and that the flu vaccine you are taking is directed at those strains in particular, so again, in my case, I don't usually get the flu vaccine, but of course you should make the decision that is right for you, for example if you have family members with compromised immune systems, work in a school or believe If you are exposed to many flu or are concerned about transmitting the flu to any individual or group of people, those are all things to keep in mind and, of course, talk to your doctor.

I will also say this, and that is that I mentioned that I have dealt with getting colds or flu at a rate of about once every 18 to 24 months and when I say cold or flu I mean a serious one that keeps me in bed where I have a fever and I am sweating a lot. what have Idone and What I keep doing is because I pay a lot of attention to how well I'm sleeping or different life events, my different workouts, etc., and I put them on my calendar and I have little hand to do it, so I just takes about 30 seconds each. day, well this worked, it was kind of a level seven out of 10 intensity, I slept well last night or I slept poorly, I know what's good for me when I sleep poorly.

I mean, that's about the level I'm recording these things I've been at. able to go back and look at the events that preceded when I had a cold or flu again. I don't know if it was a cold or flu or not, but before I got sick and I have seen, for example, if I have ever done two intense workouts in one day, something I no longer do. I tended to get sick after that if I tended to do intense workouts and then expose myself to cold temperatures while traveling, especially when traveling abroad. Those colds or flu, which again for me are very rare, so it's a limited data set.

This is completely strange data, meaning it's related to my own history of colds and flu, but it's something I really recommend people should pay attention to. When you started having symptoms, pay attention to when you got over what you think is a colder flu and then look at what happened in the days leading up to that day. I don't think it's possible to do very precise forensic analysis. a colder flu, I mean, you could have gone to the gas station, put your credit card in the machine, you know, get a drink out of the refrigerator and get a colder flu from the refrigerator handle or the credit card machine. credit. or even the gas pump, you just don't know;

However, if you look at the pattern of behavior, travel, sleep, exercise, the types of interactions you had before you got a bad cold or flu, you will likely learn something interesting and be able to avoid getting a cold or flu. serious at least to some extent in the future and I think I have done it quite successfully because I can tell you that the frequency of the colds or the flu that I have contracted has actually been decreasing. from year to year, so a decade ago I tended to get a cold or flu probably about once a year and in some cases even twice a year, although that was pretty rare and actually expanded to about once every 18 months and then in the In the last five years I think I've gotten sick twice pretty seriously with a colder flu and then once with a kind of mild cold.flu, so I tell you all that just as an example of how you can start to thinking about how their immune system interacts with different types of behaviors, different types of situations, so that they can learn something about their immune system and what will best protect them. against colds and flu in the future, which of course is a great thing because we all think we can go out, be around people coughing and sneezing, we can go to the gym when it's crowded and in the winter, oh that person thence.

Do you know how to cough? But I'm going to stay a few feet away, it's not a big deal, and while I don't want to turn anyone into a hypochondriac, that's how you get infected, that's how you get colder liquid at the same time. I don't think anyone should get to the point where they're afraid to go to a gym or go to the workplace, but I'll say it again: if you're sick with a colder flu, if you cough and sneeze. blowing your nose, having runny eyes and going to work, the gym or public transport and telling people I'm not contagious, you're lying.

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Now, of course, I strive to consume healthy whole foods for the majority of my nutritional intake every day, but there are a number of things in ag1, including specific micronutrients. which are hard to get from Whole Foods or at least in sufficient quantities, so ag1 allows me to get the vitamins and minerals I need, probiotics, prebiotics, adaptogens and critical micronutrients, so every time someone asks me if I should take the Just One supplement, what is that supplement? I should tell you ag1 because ag1 supports many different systems within the body that are involved in mental health, physical health and performance to try ag1, go drink a1.com huberman and you will get a year's supply of vitamin D3 K2 and five packets of ag1 free trip again, that's drinking a1.com huberman now the diabolical thing about the flu virus is that, just like the diabolical thing about the cold virus, you start shedding the virus, meaning you're contagious about 24 hours before of the appearance of the first symptoms.

For you, that means you can be a flu viral vector even when you don't have symptoms, that's just the unfortunate aspect of these viruses. They are very intelligent, they have no brain, but these viruses have adapted to spread from one host to another. From host to host, they have the drive to stay alive and infect more hosts, so even though they don't have a brain, they have a kind of let's call it viral intelligence and, as I've said several times, you do have it. you still have symptoms of the coldest flu, you are contagious; However, regarding the flu, you are most contagious during the three days when you feel the absolute worst, when your fever is at its worst, we will talk a little about how to deal with the fever. later, when you cough and sneeze, headache, all that, when that's at its peak, that's when you're most contagious, so again I realize that people can't always avoid contact with other people, you know living under the same roof, sometimes the caregiver is interacting with the person who has a cold or flu and I want to remind you of something I said before, which is that just because you come into contact with a colder flu doesn't necessarily mean that you will get it. a cold infection. flu, whether or not you get a colder flu depends of course on whether or not you come into contact with it, you can't catch a cold or flu that you've never come into contact with, just as you can't get eaten by a shark if you never go to the ocean;

However, the likelihood of catching that cold or flu, getting past your immune system's barriers, and becoming infected will be strongly dictated by the different aspects of your immune system for which it exists. There are three main aspects that we will talk about below and of course the things that you do to support those three aspects of your immune system. Well, let's talk about your immune system and I must confess that although I have spent more than three decades being a student and researcher of the nervous system, the immune system is great and I say that because it has this incredible elegance and logic, it basically consists of three main lines of defense, there is a physical barrier or rather a set. of physical barriers that exist between the organs of your body and the outside world and you are probably immediately thinking of skin and yes, it does indeed include your skin, but also some interesting things like the mucosal lining of your nose and mouth and even some of the liquids. that are on the surface of your eyes, we will talk about them in a moment, then there is a second line of defense which is for any virus, bacteria or fungus, but today we will talk about viruses, colds and flu, any virus. that overcome the physical barrier of the skin and mucosal lining of particular regions of your body, then you have what is called the innate immune system.

The innate immune system is this very generalized response system. It is general in the sense that it displays a basic set. of neurochemicals that are not specific to the particular virus that has entered your body, so not only are they not specific to a particular cold serotype or a different type of flu virus, but they do not even discriminate between cold or flu. Call the innate immune system it is a generalized response system to go fight viruses, so it could be a cold, it could be the flu, it could be a bacteria, it could be a fungus, it could even be a physical object and its system.

Innate immune responds by saying okay, let's take care of this now, the third component of your immune system is what is called the adaptive immune system and I touched on this aspect of your immune system a little earlier. The adaptive immune system is the aspect of your immune system that recognizes because the innate immune system told you that something has infected the body at some level in some organ or set of organs and there is an emergency and the adaptive immune system comes in and in a way very specific figure out what kind of proteins you need to produce that.

There are antibodies to combat that specific serotype of virus. So the immune system has a physical barrier component and it's not just about the skin. You have other things too, you have your innate immune system, which is this generalized response system, and then there's the adaptive immune system. Let's talk about the physical barrier component first and this is a really good opportunity for us to take a quick step back and realize that whenever we talk about our physiology there will be a mechanical set of characteristics and there will be a chemical set of characteristics, so now we are talking about the immune system and the mechanical or physical characteristic of the immune system is this barrier between the organs of our body and the outside world and the most obvious of them is the skin.

They are contained in this bag of things we call skin, skin is not just for putting on clothes and adorning yourself with jewelry or tattoos, if that's your thing, watches etc., your skin is a living organ in itself, I believe we are further. I'm used to thinking of the heart, lungs, liver and brain as organs of the body, but the skin is also an organ of the body, it has a lot of different layers of cells from the outside to the inside, they are actually the skin cells. they themselves are produced in the deeper layers of the skin and they migrate to the surface of the skin and on the surface of the skin on top of those cells and those cells produce different types of chemicals that actually serve as antibacterial and antiviral agents. meaning that if a cold or flu virus or other type of virus lands on your skin, it can neutralize and kill it, so your skin is a very important physical barrier against viruses like cold or flu getting in to your body and infect other cells. and knits now your skin is not with you, which means it has holes in it, so let's think about those holes for a second as we go from head to toe.

It's pretty obvious that your eyes have these two openings and those are openings in your skin just like you. open your eyelids underneath are your corneas, the bright part of your eyes and a little further back, on the back inner lining of your eyeball, you have a very thin layer of three thick tissue cells that we call the neural retina and I say this. because the neural retina is actually a part of your brain, so you have two parts of brain that line the back of your eyes and that's the light sensing tissue in the back of your eyes.

Now I say this because what this means is that it is a There is a short distance between the opening in your skin that we call your eyelids and your brain. Now most of the brain, of course, is contained in the cranial vault within what most people call the skull, but your brain is not very far from those openings that we call your eyelids, as a result, on the surface of your eyes, those corneas, the bright part of your eyes on the outside, there are a lot of different chemical characteristics, there are tears produced by the tear glands, but there are also a lot of antibacterial agents that actively kill things that could potentially infect your body could reach to your body, maybe even your brain, if you ever wake up in the morning and you have a scab in your eyes and you look at that scab, that kind of yellowish thing. sometimes it's yellow, I know this is a little gross, they are actually dead bacteria that your eyes have successfully defeated during your night's sleep, so when you clean them, you are taking the casualties of a war that you won during your night's sleep and you're removing them now as we go a little bit further down the face, of course, they're the nostril openings and the nostril openingsThey tend to be a little sticky, they are moist, sticky and warm, you don't need to put your fingers on them. take them off right now, you know they are wet, sticky and hot, take your fingers out of your nose please, the mucous lining of your nose is actually a very important substance that is sticky to trap viruses like cold and flu, and then the chemical components within the mucosal lining can neutralize them.

That's the best case scenario. Of course, there are scenarios in which the cold or flu virus takes up residence in the mucosal lining and can return to the sinus passages and can then infect other cells and tissues. of your body because the virus replicates and spreads throughout your body and then going a little further down, I realize that it's obvious that you have your mouth and what's really interesting is that your mouth also has a mucosal lining which is sticky and has chemical components to neutralize incoming viruses, but we know that the type of mucus and the type of bacteria that live in the nose and mouth are very healthy for you and promote healthy functioning of the immune system, which acts as a way to neutralize the viruses inside the nose and mouth are very different, so your nose and mouth may seem similar to the level of well, it's warm and sticky, there's mucus, but they are very, very different tissues, of In fact, if you think about your mouth, it is this incredible structure that not only allows you to eat, inhale and exhale, although I suggest that most people breathe through their nose for most of the time of the day and night, if you can, of course, sometimes you have to breathe through your mouth, but keep this in mind that you have this big opening in the front of your face and bacteria go in there all day, viruses go in there all day and, in In most cases, it is successfully fighting those viruses and bacteria because the mucosal lining of the mouth and nose, and the microbiota, the small microorganisms that have resonated in your nose and mouth are helping to fight bacteria and viruses, as long as the microbiota is diverse and the type that you want, which we will talk about a little more later and then we will go down further.

Throughout the body, of course, there are other openings in the skin barrier, namely the urethra of the penis or vagina and of course the vaginal canal, so the genitals of course have their own mucosal lining. and, as you can imagine, he is different in terms of his physique. makeup and its chemical composition of the mucosal lining of the nostrils and mouth and then, of course, we have the rectum and the anus, which is the exit route for the intestines, which are post-design and, frankly, you need to There's more data to really sort this out, but it seems like the main entry site for viruses into the body tends to be the eyes or mouth and we can get into some of the reasons why that would be the case, but if you remember our conversation about Since colds and flu exist in the world whether in the form of aerosols or on the surfaces of objects or on the surfaces of the skin, then what I am going to tell you next will make it so obvious why the eyes and The mouths are the main sites for colds and flu, and if you keep this in mind, there is a good chance that you can avoid many colds or flu that you would otherwise get, so before we talk about the important functions of the innate and adaptive immune system for keep colds and flu at bay.

I will tell you that you have a problem and that problem is that you tend to touch your eyes very often, in fact, you tend to touch your eyes more often after shaking. Someone else's hand now, why am I bothering with you guys? Well, actually, no. I'm getting upset with all of you and I'm getting upset with myself because there have been several studies, mainly from the Noam Soel lab at the Whitesman Institute, that show that when people meet another person and shake their hand, they touch their eyes. or they touch another region of the face very close to the eyes or they touch their mouth with their hand.

Now there are a lot of theories about why people do this. There is an idea that people actually sniff their hands, and in particular, sniff their hands more frequently after shaking another person's hand as a way of detecting what signs of chemotherapy exist in the other person, not necessarily consciously smelling the other person's scent, but rather. some type of unconscious mechanism by which we take chemicals from the person we come into contact with and bring them to our nose, our eyes or, in some cases, our upper lip and our olfactory system, which are the neurons that exist right behind the back.

The ones in our nose process that information and get all kinds of important information about how stressed the other person is, their hormones, um, whether we recognize them or not, the fact that they are different from us, that's true, we smell each other too to ourselves all day. has shown that people walk with their own smell in the cloud, we tend to touch our armpits, we tend to touch different aspects of our body, yes, and we smell ourselves several times during the day. All this is done unconsciously. I guess some people do. do it consciously and that there is a lot of information about our physiology and health and when we do this after shaking someone's hand, there is a lot of information about the physiology and health of the other person, that our nervous system, our factory system and deep parts of our brain. that are involved in primitive type behaviors, but there are also some pretty sophisticated behaviors being taken into account now that Noom soel was a guest on the hubin Lab podcast.

I encourage you to watch that episode if you have time, it's a fascinating journey into the olfactory system and not just consciously smelling or sniffing things, so we say oh, that smells good or that smells bad or that person you know is someone I want to mate with or hang out with or avoid. It's also unconscious processing of so-called chemotherapy signals, chemical signals, but the reason I mention these studies now in the context of colds and flu and how to avoid getting colds and flu is to remember that we are quite programmed to touch our own face with our own hands at the level of our eyes and nose. and the upper lip and around the eyes very soon after touching another person's skin and if you are aware of this, you can avoid bringing colds or flu to your face.

By doing so, you're going to short-circuit a lot of other important biological functions. processes involved in understanding what is happening in your environment because it does not bring those smells. I suppose that's possible, but in regards to avoiding colds and flu, it seems like a pretty good trade-off to me, so the point I'm trying to make here is that in order for you to get a cold or the flu, that virus cold or flu, the small particles of the cold and flu virus must enter your body and the main entry sites are the eyes, nose, mouth and the main actions by which we bring cold and flu viruses to your eyes, nose, and mouth by touching other people or touching other surfaces that have the coldest flu virus on them, just to remind you that the cold virus can exist for up to 24 hours on a given surface.

The flu virus tends to die after about 2 hours on a given surface and we bring it to our face, we are literally bringing the virus on ourselves, so a little more awareness of that fact means you can probably avoid colds and flu to some extent, it's not clear how well. It's not clear because, as you may recall, some people have and are spreading the cold or flu virus before any symptoms, and of course, you may be able to walk into an aerosol cloud of cold or flu viruses even if you don't. There is a person there and you are not.

Don't come into contact with them, but I think a little awareness about these colder flu virus pathways can reduce your chance of getting colder flu, and of course I'm not encouraging people to ever I touched them. An important part of social connection and social bonding, but if you start thinking about these entry portals for the cold and flu virus into your body, then you know that maybe you could think twice before hugging someone and kissing them on the face. cheek for a while. where you're actively trying to avoid getting the cold or the flu now I feel a little weird sharing this information because again, I don't want to encourage, it's always going to be at arms length, you know, you know, fist bumps. false.

You know that keeping a distance from each other again, contact is an important component of social connection, but since today's topic is cold and flu and how to avoid getting colds and flu, just like a shark can't eat you if you don't come in In the ocean there is a much lower chance of getting a colder flu if you don't touch a lot of hands and put those hands to your eyes, nose or mouth. I guess there's a way around the hugging type. Shaking hands is simply being aware of the fact that when you shake someone's hand you are very likely going to touch your eyes or face in the next 30 seconds or so and you might end up being that person who puts some sanitizer on. hands. your hands can sometimes feel a little uncomfortable doing that right in front of someone, you know, it's like sending a signal like, hey, I don't want to get infected, but guess what you don't want to get infected, okay?

Imagine that a cold or flu virus enters your system, passing through the physical barrier of your skin and mucosal lining. Now you have in mind all the different ways it could happen and all the different ways it could be

prevent

ed, but we're starting at a Point here a hypothetical point by which the colder flu virus has reached your body. Your immune system has an absolutely exquisitely sophisticated way of knowing you against other cells within your body that are yours and cells in your body that are other organisms or viruses from the outside world and when viruses like the cold or flu virus are detected in your body, your body may not even recognize that it's a cold or flu virus, it may not even recognize that it's a virus, it just knows that this thing that's in me it's someone else's it's never me I had seen before this is not me these are not my cells these are not the chemicals that I am producing and your immune system is amazing that way and when your innate immune system launches a response, what is that response?

Well, first of all, the response is very quick. The coldest flu enters your body and your innate immune system immediately or almost immediately launches an attack against that invader or invaders because as soon as the virus arrives. in your body it will begin to replicate as quickly as possible. What happens, the white blood cells that your body produces will go to the sites where those viruses are and, by the way, those viruses basically enter the cells of your body and then hijack the genetic machinery of those cells to replicate inside those cells and then get out of those cells and then infect more cells, that's how these viruses work.

Your body produces white blood cells, things like neutrophils, natural killer cells, macro, these are what we call acting affective cells. as a kind of ambulance system and go to the sites where those viruses exist and the cells that they have infected and start trying to physically block them and also use specific chemical mechanisms to neutralize and kill those viruses again anytime you think of Biology thinks that the mechanical and chemical characteristics of a response are now a key component of the innate immune system. What's called the complement system is not the complement like oh, you look great today, but complement well, the complement system that exists in the plasma within your blood, these are chemicals in the bloodstream that go and mark specific cells that have been infected or viruses with a signal, a chemical signal that essentially looks like an "eat me" signal to these other types of cells in your immune system, so those natural killer cells go around the body and go looking for the cells that have this "eat me" signal and try to destroy those particular cells.

The other thing that the immune system does when it urinates is that the cells that have been infected and are suffering damage remember that they have the coldest flu virus inside them and they are hijacking the cell or the machinery of those cells and using it to produce their own virus, more viruses and, as a consequence, the genetic machinery of those cells cannot do many other things that it normally can do or at least not as well, those cells that are really suffering release a help signal and then , in response to that signal, help me. Your immune system releases what are called cytotypes, things like interlukin 1, interlan 6, tumor necrosis, alpha factor, just fancy nerd names for different ones. types of molecules that go to the site of infection and try to help or helpeliminate that infection and also help repair the cells that have been infected by these viruses, now one of the mechanical or physical consequences of these chemical signals. like Incan 1 Incan 6 tnf Alpha again, those are all types of cytos that are attracted to a particular cell or region of cells that have been infected and create some physical swelling of the area, impact the vasculature, the veins and capillaries that feed that area and in response, they put more blood there, so it swells a little or, in some cases, histamine is released.

Well, we thought about antihistamine medications. Well, histamines are an aspect of your immune system, they move around your body this way. Really cool cells called mast cells More masses of cells and when histamines are released that area gets hot and swollen, it's what we call edema and that whole area is marked really a sight, like the site of an accident on the side of the road. like hey, we have eat me signals to get the debris and bad stuff out of here, try to get those viruses out of here, we have help signals to try to help injured cells, just like you would do with people. in a car accident and there is a lot of swelling so there is extra blood flow, sometimes there are other physical characteristics as well.

Now the important thing to know is that the innate immune system is very fast and is in fact independent of the type of infection. It doesn't even matter if it's a bacterial, fungal, or viral infection, but you certainly don't pay attention to the exact serotype of the cold virus or whether or not it's H1 or another type of flu, so it's one way to Think about the innate immune system. The system is that it is a very rapid and non-specific response to a virus or other type of invader. That's all a lot of biology, but if you think about it, let's imagine a scenario where you go to a party and you hang out at the party that you don't.

I don't see anyone coughing or sneezing, but maybe a person has a cold virus or they have a flu virus and they're not even aware of it, they're not going to have symptoms until the next day, or that's what you talk to that. person you shake hands with maybe you touch your eyes maybe not, but you are exposed to that coldest flu virus you go home you go to sleep you wake up the next morning you feel fine and then in Sometime the next afternoon, you know you start to feel a little tickle in your throat or you start to feel a little fatigue or discomfort, do you have that colder flu?

Well, possibly okay, we don't know for sure, but assuming that cold or flu virus did indeed get into your system, then your immune system is starting to create a set of responses that we talked about a moment ago, but also It tends to impact things at the level of your brain so that you feel like you know I'm not feeling quite right. I feel like I'm not feeling very well and there are a lot of reasons why you would feel that way and we'll talk about those reasons a little bit later, but does that mean that you're necessarily suffering from a colder flu, well, technically yes, your innate immune system is deployed to fight this strange viral invader, but whether or not you actually get a full-blown cold or flu or, put another way, the severity of that cold or flu infection depends on whether or not your innate immune system can fight that colder flu from the beginning and in fact, there are many cases where we believe that when you are exposed to a colder flu, it enters your body, but your innate immune system is enough to overcome it and fight it.

This is one of them. of the reasons why it's so important that if you're starting to feel a little under the weather and think you're coming down with the colder flu, you do certain things to make sure your innate immune system is ready to launch a full-scale attack. against the colder flu virus, we'll talk about how to do it a little later. I'm not trying to hide it, it's just that it's important to understand that just because the virus enters your body doesn't necessarily mean that you're going to get a full-blown cold or flu, and in fact, the innate immune system is sometimes enough to prevent that colder flu from reproducing enough that you have the full set of symptoms and that's kind of an ideal scenario, so we're definitely going to talk today about what to do if you start to feel a little bit unwell, what do if you find out that, oh, you know that person I was with at the party last night, who is really sick with a colder flu because there are things you can do to increase the likelihood that your innate immune system can handle battle enough that you never have to move on to the next component of the immune response, which is the adaptive immune response that I would like to take.

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The most important thing to understand about your adaptive immune system is that, as its name suggests, its job is to create antibodies specific to the same intruder that entered you and infected your cells, the very specific serotype of the cold virus, the very type specific influenza, so you defeat that virus, but then, in a surprising way, your adaptive immune system also maintains a memory of that battle and keeps it inside your body, believe it or not, within a population of stem cells , which are cells that can become more cells, so if you ever encounter the same serotype of cold virus or the same strain of influenza again, your antibodies can immediately neutralize that coldest flu virus, the system adaptive immune system has the ability to produce proteins that have a particular shape on their surface that matches the shape of what your immune system is trying to kill now the adaptive immune system has two basic phases in the first phase the adaptive immune system produces these things called immunoglobulins IGS and immunoglobulins come in different forms there are IGG, there is IGM, there are other types of IGS as well, for the sake of today's discussion know that the initial wave of antibodies that the adaptive immune system produces or of the IGM variety and IG antibodies can travel and adhere to the surface. of the coldest flu virus and it matches quite well, it's not perfect but it matches quite well, think of, for example, a particular serotype of cold virus or the H1N1 flu virus, having a very particular outline on its surface, The M approaches that contour.

So it's better at fighting the colder flu virus than the innate immune system, but it's not a perfect fit. However, the adaptive immune system doesn't stop with producing those igms, the adaptive immune system takes that information on how accurate or inaccurate it is. The fit is between the IGM antibodies and the surface of that particular cold or flu virus and then, in a surprising way, it signals stem cell populations in the bone marrow and other tissues and then more antibodies of the variety come out. IGG and the IG. The proteins are very specific for the form of that particular cold or flu virus, so the Iggs can define and neutralize those viral particles.

So when we talk about the immune system, we're talking about a physical barrier that, if it's broken down, a cold or flu virus takes up residence and starts replicating, the innate immune system launches a widespread attack against that colder flu virus. and then the adaptive immune system kicks in, usually a couple of days later, first with the production of antibodies that are quite specific for the particular virus. virus that arrived in the body and infected the cells, but then there is a second wave of antibody production and those antibodies are incredibly specific for that particular cold or flu virus and as I mentioned earlier, the adaptive immune system acquires a memory of the specific fit between a certain antibody that you produced and the viral invader and the successful battle that those antibodies waged against that viral invader and that memory is maintained in such a way that if next week or next season you encounter exactly the same virus serotype from the cold or the same type of flu virus, then you already have antibodies ready to be used, sometimes the antibodies continue to circulate in your system, sometimes you need to generate more and the immune system is so amazing that it can send a message to that stem cell.

The population in the bone marrow or elsewhere says Hey, listen, this virus that we defeated a few weeks, months or years ago, it's back, we need more antibodies and boom, your adaptive immune system produces those antibodies and kills the virus now, like final point about the immune system I've been talking a lot today about cells traveling and killing viruses and sending signals eat me, help me, etc., it's important to understand that while cells can migrate through the body, a lot of what we're talking about here It is the movement of proteins through the vascular system through the blood system of the body, but there is another system that is very important for all of this that collaborates with the vascular system and that is the lymphatic system.

We don't have time to go into a full lecture on the lymphatic system. system, but suffice it to say that the lymphatic system can extract things from the blood, like viruses, but also cells that have been hit or cells that have been ingested and that are contained within other cells, such as macrophages, and it can filter out those different cells. types and can produce its own useful chemicals that can then be reintroduced into the bloodstream to help fight the infection. Now this becomes very important when later we talk about how specific forms, intensities and durations of exercise can increase the capacity of your innate immune system. system to fight infections, so your adaptive immune system may not even have to get involved in the battle because your innate system handled it.

There is data showing that exercise of sufficient intensity and duration, but not excessive intensity and duration, can recruit the lymphatic system. system and recruit or increase the activity of the innate immune system even in the absence of an infection, so that if you go to that party and you meet that person with a colder flu, you can beat that colder flu virus right from the start and never have to do it. Dealing with producing antibodies against that coldest flu virus is fine, so now you have a pretty sophisticated biological understanding of what colds are, what the flu is, and the way the immune system works to fight off viruses like flu. colds and the flu, so with that in mind, I think now is the appropriate time to start talking about what the peer-reviewed scientific research says about how to allow your immune system to function at its best so you can fight off colds. and the flu, that is, if you are exposed to a cold or flu, that is, if it breaks the physical barrier of the skin and the mucous lining of the nose, mouth or gets into the eyes, you have a better chance of beating that colder flu at the level of your innate immune system, so your adaptive immune system never even has to respond by creating all those specific antibodies.

Now, fortunately, there are many different things we can do to improve the function of our immune system. In fact, I feel like every time the winter months roll around we start seeing the same list. A lot of things come up online and in the press and I don't want to diminish these things; In fact, they are the foundation for maintaining and improving the function of your innate immune system. So,what are those things? Some of these will be pretty obvious things, like getting enough quality sleep every night, we know, for example, that if you're sleep deprived, especially if you stay up all night, but certainly even if you only get 50% sleep or 75% of your needs, your innate immune system will be affected. is not going to be as effective in fighting the flu or colds, we also know that exercise of a specific type, a specific duration and a specific intensity can serve to strengthen the innate immune system and we will talk about the specific exercise protocols that are best suited. they can achieve.

We hear that too and it is absolutely true that we need proper nutrition if we are in a caloric deficit, for example if we are trying to diet during the winter months, something that many people try to do and which can put our innate immune system in a state of crisis. state of vulnerability. a committed state that said that things like intermittent fasting or even longer duration fasting have been implicated and here I really want to stress that they are implicated in brief improvements in immune system function, however, the fast is prolonged or you don't eat enough calories to maintain body weight for many years.

Days in a row can compromise the function of the innate immune system. I'll talk about this a little bit more in depth in a moment and then of course we'll hear about stress, that we're all supposed to regulate our stress levels and not get too stressed. and here I have to put an asterisk next to those statements because yes, indeed, chronic stress, that is, stress that continues day after day or even short periods of stress that impede our ability to sleep at night, can in fact reduce the functioning of our innate immune system. However, it is also clear that short bouts of stress, as long as they do not inhibit our ability to sleep that night, can actually improve immune system function and this is something I don't think is talked about enough. often, quote unquote, cortisol is bad, it's a stress hormone, listen, cortisol is great as long as it's elevated early in the day and not late in the day or at night, plus cortisol has thresholds beyond which, if it is too high, it can be bad for us, but it is also the case that if cortisol levels are too low, that is bad for us and it is especially bad for the functioning of our immune system because the Glucocorticoids, of which cortisol is, play an important role in the activation of natural killer cells of the innate immune system, of which they are one of the main signals by which those interlucans such as interlan 1 and interlan 6 are deployed in our body and very often we will hear that stress increases inflammation and in fact interlukin 1 interlan 6 are pro-inflammatory, you might think, oh my gosh, I don't know.

I want that, I don't want cortisol, I don't want these Incas to be elevated, but guess what, the response to inflammation is also an important component of that innate immune system that allows us to fight infections, so in trying to maintain our innate immune system alert. We realize that it is not a fine-tuned biological statement, but rather keeping our immune system functioning at its best. We want to make inflammation available as a tool to fight infection. We want cortisol to be available as a way to activate that inflammation and other aspects of our immune system that just aren't.

We want so much cortisol and so much inflammation that we can't sleep and our gut microbiome suffers and that brings me to the other component that is important for the basic functioning of your immune system so that you can be stronger when you inevitably find yourself. Those cold and flu viruses, why do I say inevitably? Look, if you exist in the world, that is, if you live on planet Earth, you will be bombarded with different viruses, bacteria, fungi and all that throughout your days, and yes, in those. winter months because people spend more time indoors and touch each other and surfaces breathe more into each other, sneeze more and so on, there is more spread of colds and flu, so if we take a step back and ask ourselves how can I have my immune system as strong and prepared as possible to fight cold and flu viruses.

We get down to the basics: making sure you get enough, quality sleep every night. Not feeling sleepy during the day, except perhaps requiring a short nap of between 10 and 30 minutes. Not everyone requires it, but it is perfectly normal to have a dip in energy in the afternoon that can be restored with a short nap or a deep break without sleep. We will provide links to sleepless breastfeeding tools and other tools in the show notes titles that you know are zero cost tools that will allow you to get your energy back. Some people just take a nap and that sort of thing if you want tools to improve your sleep and make sure you're getting enough, quality sleep each night, we'll also provide you with a link to our zero-cost sleep toolkit that details that in PDF format it just lists the things you can do or take if that's your choice and so on and so on and of course we've done episodes on quality nutrition and what that means, we've done episodes on stress and how to combat it and we've done episodes on called gut microbiome, but right now I just want to mention that the gut microbiome, which is trillions of little microbacteria that interact strongly with the immune system and help support the immune system, you want to keep the gut microbiome healthy, so you'll notice that we included some tools related to the gut microbiome here in a moment and this is very important, keep in mind that the microbiome does not only exist in the intestine.

Nowadays we hear about the gut microbiome a lot and I am very happy that the gut microbiome is receiving the attention it deserves in the context of mental health, physical health and performance, but we cannot forget that the microbiome also exists on the surface of the eye and in the nasal passages and, in fact, the microbiome that is specific to the nasal passages. The nasal passages, as I mentioned before, are very different from the microbiome that exists within the mouth and the microbiome that exists within the mucosa of the nasal passages appears to be the most effective at fighting any viruses that we encounter, especially cold viruses and the flu, so ideally you would never encounter a colder flu virus, we know that if colder flu viruses enter through your nasal passages, you have a better chance of fighting off that particular cold or flu, So what does that mean?

This is where I can make a strong effort to be a nasal breather (certainly you want to be a nasal breather while you sleep, but also throughout the day, unless you are talking or exercising hard enough that you need to breathe through your mouth or unless you you are eating, being a nasal breather is known to provide the right environment to keep the nasal microbiome at its healthiest state and promote the diversity of microbiota in the nasal passages that can better protect you against colds and flu, and there are a number growing number of studies pointing out this fact.

I will provide a link to one that I really like titled Alterations in Nasal Oral Finger Microbiota and Salivary Proteins in Mouth-Breathing Children. This is just one study that points out the fact that breathing through the nose is a good thing for children who breathe through the mouth. and adults who breathe through the mouth, meaning that children and adults who default to mouth breathing tend to have more upper respiratory tract Cs, including colds and flu, consciously focusing on nasal breathing is one of The best things we can all do to combat any cold or flu we might encounter, earlier we talked about trying to avoid touching our eyes at least without washing our hands first or sanitizing them first after meeting someone, keeping in mind that most People do it unconsciously.

Here we also say when you enter a room where you are hanging out with people, whether you are waiting for public transportation or you are at work or walking down the hall, unless you are exercising a lot, unless you are talking, try Beyond concentrating on breathing through your nose, there are many other things. There are also reasons to be a nasal breather, but this is one of the main ones and I will provide a link to another reference which is the book Jaws by my colleagues at Stanford, which talks about nasal breathing and the importance of nasal breathing, but also The degree to which children and adults are exposed to higher levels of viral and bacterial infections, but viral infections in particular when they rely on mouth breathing and the incredible benefits of doing this very simple zero-cost thing as long as you can consciously remember to breathe through your nose instead of breathing through your mouth and just as an added point about nasal breathing because I can't resist telling you this.

I think it's great, such an interesting adaptation when we breathe through our nose we heat the air. a way that is very different from the way we warm the air when we breathe through the mouth and by warming the air entering the nasal passages, it changes the likelihood that colder flu viruses will successfully embed themselves in the lining of the mucosa and infect the underlying cells and enter. the other cells and tissues of our body, so this whole nasal breathing thing is important and effective at the level of regulating the temperature of the millu inside the nose and, therefore, the viruses that end up in the nose, as well as the mucosal line and chemicals. done by the mucosal line and again the nose is a very different place than the mouth.

In fact, I will provide a link to yet another article titled Human Nasal Microbiota. It's a really interesting article. It is actually an interview with an expert scientist. on the nasal microbiome talking about how this structure inside our nose is actually the main site of defense by which we destroy potentially incoming viruses, so if that sounds too simple, just breathe through your nose, it's very simple but it's also very effective now , it is also clearly the case that maintaining your gut microbiome is advantageous to keeping your innate immune system at its most robust level of functioning and I should mention that your gut microbiome is not just about your stomach, you know, we hear the word gut and We think of stomach, but it's actually Throughout the entire digestive tract from the mouth to the other end, there are different microbiota in different places along that mucosal tract and there are a couple of things you can do to make sure that the gut microbiome is best supported along that tract.

To the full extent, the first one is that and it was covered in the episode that we did with my colleague Justin Sonenberg, who is a world expert on the gut microbiome and is to consume two to four servings of low-sugar fermented foods per day, for what things like sauerkraut things like kimchi things like kefir things like kombucha it can be a little tricky to determine which of these you like and which ones you're willing to consume on a regular basis, but it's pretty clear that the brine you know that kind of salty solution around the sauerkraut and by the way when I say sauerkraut, what we're talking about here is the kind that needs to be refrigerated, it contains what are called live cultures, unlike sauerkraut which can exist in the non-refrigerated portion from the store or pickles that also have brine in them and that need to be kept in the refrigerator before you even open them and of course like yogurt, which has active live cultures, those are the kinds of things that will help the best. the diversity of the microbiota throughout the entire gut microbiome, so that your gut microbiome can do its job of supporting your nervous system, but here, especially in the context of today's discussion, your immune system is now important the low-sugar component of low-sugar fermented foods. because what we know is that if you consume yogurts with a lot of sugar or kombucha with high levels of sugar or you consume pickles or sauerkraut that contain a lot of sugar, you are probably going to start creating other problems related to sugar, what you are really looking for are these foods fermented ones are low in sugar and can be a little difficult to find in the store, but they are usually there and once you identify the ones you want, you should really aim for two to four servings of these per day.

You can also consume a prebiotic or probiotic in capsule form, such as ag1 athletic greens, which also contain prebiotic probiotics, but it is very clear that consuming two to four servings of low-sugar fermented foods per day are among the best ways to promote the health of the gut microbiome and that the microbiomeGut is so important for keeping your innate immune system thriving so that you can fight off the colds or flu that try to bombard your system. Now there is another tool you can use to improve your gut microbiome. I have to warn you that this one might make some of you cringe a little, but this is one I started using about four months ago.

It's interesting. It goes back to some older, quote-unquote traditional medicine practices, but it makes a lot of logical sense to be fair. I don't know of any randomized control trials exploring the use of this protocol, but it is very simple and completely free and maintained. so strongly in the logic of how the gut and oral microbiome work that, frankly, I started doing it and you know if it's a placebo effect or not, I don't know, but I feel better and it's very easy to do and it potentially means improved fun of your gut microbiome enough so that it at least shares it with you and then you can decide what this protocol essentially consists of is before you go to sleep at night or in the morning you pour yourself some water any water you consume only clean water and clear and then you take a sip of that water when you wake up in the morning and you swish it around in your mouth and then you swallow it now for those of you who are like, oh, gross.

Let's think about this: is it really gross to swish a little water in your mouth and then swallow it when you wake up before brushing your teeth? Of course, it may seem gross to you, but all night long when you're sleeping, especially if you breathe through your nose, while you're sleeping, the environment inside your mouth is such that you're creating a lot of bacteria, you're creating all these little microbacteria that potentially They can inhabit your digestive tract and provide at least some of the substrate. so the microbiota in your digestive tract can thrive and if that sounds gross to you, keep in mind that that's what having a healthy gut microbiome is really all about, so the protocol is very simple and cost-free: take a drink of water, shakes and swallows it.

Interestingly, it doesn't taste bad, in fact, it will just know how to swallow it, and it actually knows how to swallow some water, it's not like it tastes like bad breath or anything, it's a very simple protocol. which again there are no randomized control trials, but it's really based on the logic of how the oral microbiome and the gut microbiome interact and because what we're talking about here is supporting the function of your gut microbiome in a way that supports the function of your innate immune system. so that you can avoid colds and flu, at least to me that seems like a pretty low bar.

Yes, okay, so to boost your internal immune system you should get a good night's sleep as often as possible. You should support the gut microbiome in the ways we just described. What about exercise? We hear it all the time. Exercise is so good for us that it improves the immune system and so on. Listen. I am a big believer in exercise. Personally, I like to do three sets of cardio. per week, one long, one medium, one short and I do three sets of resistance training each week. All of that and specifically what I do is available to you as a zero crossing protocol in PDF form.

We have a link to that in the program. notes subtitles I also have a whole episode on fundamental fitness and such, the discussion we're going to have now is about what general forms of exercise really support the innate immune system and this is really important, what forms of exercise actually deplete your system innate immune system. This is not talked about enough. I think there are certain intensities and durations of exercise that make us more vulnerable to colds and flu, so let's discuss that before we do it. I want to talk briefly. I touch on something that I hear a lot, which is the question of whether I feel a little worn out if I exercise or not and to be honest, there is no easy answer to that question, it is impossible for me or you to know whether or not, you were exposed to a cold or flu and you are starting to fight it at the level of your immune system Nate or whether you feel or not you just feel a little sluggish, however, what we do know is that if you feel discomfort at the level of the body as if your body felt different feels heavier you feel tired you feel tired at a time of day that doesn't make sense given your usual patterns of being tired you're feeling tired in a way that doesn't make sense given the amount of sleep you got the night before .

I mean, what we're talking about here is ruling out any potential stressors in your life, you know, staying up too late or drinking caffeine at night. At the wrong time or something, what we know is that if you feel that general discomfort throughout your body, there is a good chance that you are suffering from something and that your best response would be to go home. take a hot shower or bath. I'll explain why you would want to do it in a few minutes and then go to bed early and even if you can't fall asleep you should just be as still and relaxed as possible, we know that if you push yourself to do bouts of intense activity or even just push yourself to do an activity when you feel exhausted at that whole-body level, maybe a little tickle in your throat, you're going to compromise the function of your innate immune system and you're very likely to get sicker than you would otherwise, so this is my suggestion, if you are starting to feel exhausted at the level of discomfort in the whole body or just not feeling well, it is better that you take a hot shower bath and lie down in bed or just lie down and try to rest and Get enough sleep, probably even a little extra sleep, and here's why that whole-body discomfort, that extra fatigue that's not easily explained by other factors in your life.

It has to do with the fact that when your innate immune system is activated, meaning you're already fighting off a cold or the flu, interlukin 1 and interlukin 6 have a way of interacting with a particular area of ​​the brain called the dorsal rafay nucleus. , which is a block of choa full of neurons that release serotonin and serotonin from Rafay's dorsal nucleus act in specific regions of his hypothalamus, areas such as the preoptic region for those who want to know and other areas of the hypothalamus that generate a state of drowsiness, also when we get sick our sleeping patterns.

Instead we feel like we need to sleep more but we don't feel as rested from that sleep and that has to do with the ways that serotonin interacts with some of the components of the brain circuit involved in sleep that controls slow wave or deep sleep. and this is a whole discussion in itself. I actually covered a lot of the mechanistic aspects of this. The topic of immune-induced sleepiness and Malay is associated with feeling sick in an episode about interactions between the neural and immune system which I will also provide a link to in the show notes titles, but suffice it to say if you feel like Mala's whole body is and especially if you also have a little tickle in your throat, it just doesn't feel right, you're not used to feeling like that at that time of day or night, so I encourage you to rest because it's You are probably already fighting an infection, however, if you go out a lot during the winter months or interact with a lot of people by virtue of work, public transportation or any gym, etc., you are a school teacher, perhaps your children. you're coming home with colds and flu and you still don't feel that discomfort you don't feel any tickling in your throat you don't feel that kind of burning or tickling inside your nostrils when you breathe you know we're We're all familiar with these things, the watering of the eyes that precedes a full-blown cold or flu.

Well, if you're not experiencing those things and you want to keep your innate immune system strong and able to fight off colds and flu, then we know that exercise can be a great way to increase the output of that innate immune system. What I mean by this is that the right intensity and duration of exercise can act as a stressor that promotes some inflammation and the release of cytotypes and a little activation of the innate immune system, including the production of more white blood cells. , natural killer cells, so you're causing the innate immune system to almost think there's something to fight, so if you ever encounter an infection, you can beat it. from the beginning, so let's be detailed here about what we mean by proper exercise intensity and duration.

There is a wonderful review that was published in 2019 in the Journal of Sport and Health Science titled The compelling link between physical activity and the body's defense system and there is a lot in this review article, but I will only highlight some of the critical features that They will relate directly to the protocols that I think all of you will be interested in, first of all, we know that exercise that lasts 60 minutes or less and that is intense but without total effort, okay, here we are not talking about the percentage of the single repetition maximum weight.

We're not talking about 70 to 85% of VO2 max here. We're talking about you're subjectively measuring what a 10 out of 10 effort is like you can't do more, you can't contribute more effort to that set of exercises and that's true whether we're talking about strength training exercises or not. resistance or cardiovascular exercises like running or rowing or things like that, what we know is that if you do that type of exercise for about 60 minutes or less, you promote the exchange of components between the blood and the lymphatic system that increase the circulation of those cells and chemicals within the body. innate immune system in such a way that not only during exercise but for many hours afterwards, perhaps even up to 24 hours later, the initial activity level of your innate immune system increases, allowing it to better fight infections such as colds and flu, So this is an incentive to do regular exercise of 60 minutes or less per day, which makes it of sufficient intensity for your immune system to deploy more of those chemicals and for your lymphatic and blood circulation to increase its exchange of materials. enough for Nate's immune system to become stronger.

However, it is not at all the case that more is better, in fact it is probably the case that less is better. This is what we know for sure and this review covers sort of the extreme of these examples, but for example, people who walk every day for about 60 minutes of brisk walking experience an increase in te cell function, so It's an immune cell that goes out and fights cold and flu viruses and natural killer cell activity, so they increase macro function. Now you are familiar with these cells if you don't know exactly. what they do, just keep in mind that you heard about this in the context of what the innate immune system does to go out and fight off colds and flu.

Cytoses increase, but not dramatically, okay, so this is a mild inflammation response to stress hormones like cortisol and epinephrine. Norep nephrine, also called adrenaline and norepinephrine, are also deployed, so 60 minutes or less of this moderate to high intensity exercise creates this mild stress response and an increase in innate immune system function, however, people who run a marathon and, like me, I remember that a marathon is 26.2 miles, if I'm not mistaken, they experience a very different pattern of immune response to that long session of exercise, so here we are comparing one hour of exercise with 3 hours, what it takes to run a marathon.

I have some friends who are marathon runners. I guess about three or four hours if you're really slow, but somewhere in between you know, I don't know, two and a half hours and three if you're trained and you're doing it. and you are doing them well on a regular basis, this is the point: people who have just run a marathon and people who have been training for a marathon and are approaching that marathon are severely immunocompromised, the levels of their cell function They are well below baseline, which means their innate immune system is not working as well as it would if they did not do any exercise.

Their natural killer cell activity is also greatly diminished. These are huge reductions in these cells that are in the function of the innate immune system and its stress hormones. and its inflammatory molecules, such as the cytoplasm circulating in the blood, are extremely high. Now again we represent opposite ends of the spectrum with 1 hour or less of daily exercise versus 26.2 mile marathon or half marathon exercise, as the case may be, and let me be very direct. I'm not discouraging people from running or training for marathons or half marathons. I think it's great, just understand what you're doing to your immune system when you do it andtake the necessary precautions, but I think most people who hear this.

They're trying to think of ways that they can avoid getting colds and flu, and certainly running marathons is not going to be the way to do it, but quite the opposite, the way to do it adds to the other things we've been talking about. exercise regularly maybe not every day. I actually prefer to take one day a week completely free from exercise. Usually I'll do some sauna and cold that day if I have it available, but the point is, you don't. You don't need to exercise for an hour a day to get this improvement in innate immune response.

The data shows that this improvement in innate immune response can be obtained with as little as 20 minutes per day and probably even as little as 12 minutes per day. However, if you are going to try to achieve this increase in innate immune system function or performance with a shorter session of exercise, such as 12 minutes, it would be better to make it 12 minutes of very high intensity training, in fact, that is what that corresponds to me. For me it's Friday, but it doesn't really matter what day of the week there is one day of the week where I do a very short session of cardio but I'm running hard for between 20 seconds to a minute and then I'm taking a short period of rest and then repeating that for a total of 12 minutes.

Now some people here only require 12 minutes of exercise and default to 12 minutes every time they workout. I don't think it's a good idea. We can take the law of averages here and say the following. I think everyone should do a combination of cardio training and resistance training. Maybe I think generally not on the same days, but if you're going to do that and you want to keep it up. healthy immune system functioning, my suggestion is that what I do is, unless it's a long set of cardio training that I do once a week and that for me means 60 to 90 minutes and sometimes more if it's a walk that certainly does not require so much intensity.

Suggest warming up for about 5 to 10 minutes and then limiting your total workout duration to about 50 minutes, maybe 60 minutes if that's what you need to complete what you need to do to meet your exercise goals, but be very careful. by exceeding 75 minutes of exercise in any set of exercises and if you remember at the beginning of the episode when I said that I track what I do day to day and I don't do it in a very detailed way, but I make note of when I have a flu or a serious cold. I can tell you that in almost every case where I have had a bad cold or flu, there are two things that have preceded that bad cold or flu: sleep.

Deprivation would typically be nights where I slept two hours or less for more than one night. Well, the second thing is anytime I really pushed it with exercise and did it all and went for 75 minutes and then went up to 90 minutes. and then maybe later that day because someone invited me to run or something, I also did that second run or that second workout of some kind, it could be running in the morning and weight training in the afternoon, some people can do that Training Type. even regularly and without getting sick. I'm not a person like that.

I have managed to maintain a fairly consistent physical performance, i.e. three cardio training sessions and three weight training sessions per week for over several decades and I think part of the reason I have been able to do that is because I never push myself too hard for too long. in a given workout, so this is really a call for moderation in terms of the duration and intensity of the exercise you're doing, but "We're not talking about being really relaxed, we're not talking about easy workouts, what we're talking about is speaking is an hour or less of moderate to high intensity exercise, depending on the duration of that exercise and taking into account when." you're doing that, you're activating that innate immune system, you're literally creating an immune response, you're increasing inflammation, you're increasing those types of cytocytes, you're increasing stress, stress hormones, we have to start thinking about exercise as is, what is. a form of stress that induces adaptations Dr.

Andy Galpin talked a lot about this in the series he did on exercise physiology. It's an excellent series that covers everything from strength to hypertrophy, speed and endurance, nutritional supplements. You can find all of that at Hubman Lab.com very easily exercise is a very powerful tool we know that we know that in the context of changing aesthetics like the composition of body mass you know increase muscle reduce fat we know that in the context of reducing resting heart rate reduce resting blood pressure we know that in the context of all these other health metrics, here we are talking about using exercise as a very powerful tool to increase immune system function to keep you healthy not only during the winter months but throughout the year and especially if you are sleeping less if you interact with children or adults who carry infections home from school or work on a regular basis or perhaps even work in an environment such as a hospital or clinic where regularly interacts with patients who have these One thing I am often asked is if I am sleep deprived should I exercise?

And that's a little complicated. My initial answer for many years was no, no, if you are sleep deprived, it is better not to exercise. Now I need to qualify that answer because there is data that shows that if you are sleep deprived and you exercise, especially if you do it early in the day and it doesn't disrupt your sleep schedule, it doesn't make you go to sleep even later the next day. night which can actually cause some adjustments in the function of your immune system and in the way it regulates your blood sugar level that offset some of the negative effects of lack of sleep that said you should never compromise on the amount of I dream that you can sleep to exercise in such a way that you exhaust yourself, so what I'm really saying here is that if you sleep poorly one night, you should skip your workout and you feel like, ah, you know I don't feel sick and I should do exercise or Should I go back to sleep?

Going back to sleep is probably the best idea, but if you don't have the option to go back to sleep for whatever reason you can't go back to sleep, then it would be wise to get some exercise. but I would suggest reducing the intensity and duration of that exercise by about 25%, maybe even 50%, and that should allow you to offset any of the negative effects of lack of sleep that night. Keep in mind that exercise does not replace sleep and then to allow you to sleep at the appropriate time later that night and return to a regular schedule, keeping your innate immune system fine-tuned and ready to fight off any cold or flu.

Now, one more point about exercise and here we're also going to fit in an important point about nutrition in the review I mentioned a few moments ago, they cover some of the data from studies exploring the post-exercise stress response, so This is the post-exercise induced increase in things like cortisol, those natural killer cells, white blood cell production and so on, it's very clear that if you're in a state of chronic stress because you're exercising too much and or because you're not getting enough sleep or for any reason, maybe you have a lot of life stress, it is very clear that eating carbohydrates after exercise can help attenuate part of the inflammation induced by exercise.

When we talk about carbohydrates, we are talking about oatmeal pasta with rice, that type of thing. Complex carbohydrates and fruits after exercise have been shown to attenuate and reduce some of the markers of inflammation by 30-40% compared to eating just water, especially if you train fasted, for those of you like me who They like to wake up. in the morning and just drink liquids, you know, for me it's water and whipped coffee and, by the way, I've said before that people should delay their caffeine intake by 90 minutes if and only if they're experiencing an afternoon crash, but If you exercise first thing in the morning, it's perfectly fine to ingest caffeine right away to increase energy for that exercise, that's certainly what I do on the days I exercise, but if you fast and then drink caffeine, then if you're exercising and that exercise lasts longer than 60 minutes, certainly if it lasts longer than 75 minutes you would do well to eat some complex carbohydrates, maybe also some fruit, maybe not immediately after exercise, but within 45 minutes or the hour or so after exercise. that you're not ramping up those inflammatory molecules and letting them ramp up for many hours into the morning and all day because of course this episode isn't about exercise and nutrition, but here we're talking about the role that exercise and nutrition play. to help us fight colds and flu by increasing the function of that innate immune system and the reasons why carbohydrates can have this effect on cortisol.

Etc. It's an interesting and important discussion in itself, we'll save that for another episode, but keep that in mind too. I don't know about you, but a big bowl of oatmeal, some fruit and a protein drink or some eggs after about an hour of exercise in the morning, when I haven't eaten anything since the night before, tastes really good, so keep going with the topic of things we can do at a behavioral level to improve the function of our innate immune system and fight colds and flu perhaps even prevent us from getting colds and flu but certainly help fight them off if they have initially made their way towards our system, but we have not developed full symptoms and we want to prevent those full symptoms is the use of deliberate exposure to heat, particularly the sauna.

There is a good study on this which was published very recently in 2023, the title of the study is about the effects of a single session and a series of finished sauna sessions on the immune system response and heat shock protein levels 70 in trained and untrained men. It's a very interesting study that compared athletically trained and non-athletically trained men, as most of you probably know. When you go into a hot sauna, the heart rate increases, there is vasoid dilation, there is an increase in the release of heat shock proteins, there is an increase in things like dorphins, which if it is hot enough increase to levels that make us feel a little agitated and not so much.

Well, we have to actively calm down in the sauna, so we're not talking about an easy cruise at 150° fenhe, we're talking about going up to a range of 180 degrees Fahrenheit or 210 degrees Fahrenheit, maybe even higher if you're adapted to the heat and that the dolphin makes you feel bad in the short term, but it upregulates a lot of different biological mechanisms that give you a kind of low-level euphoria and, in fact, the ability to experience more feelings of well-being thanks to the endorphins that do after leaving the sauna. It is very important to understand whether or not we are talking about exercise or deliberate exposure to cold or deliberate exposure to heat.

What happens during exposure to heat. Exposure to cold. the long term adaptation we are looking for, like exercise, increases heart rate and blood pressure but then leads to reductions in resting heart rate and blood pressure etc. this study is interesting and there are many conclusions different. of this study, because they are comparing these two different populations, I will only give you the upper outline of what the protocol entailed. There were 10 sauna sessions, each of those sauna sessions were three 15 minute rounds of sauna, so one session meant going to the sauna. the sauna was a certain temperature, but I think for most people what will work in terms of parallels with the studio will be between 176 and 210 degrees Fahrenheit, depending on how adapted you are to the heat, always be safe, don't do this . if you are pregnant don't do this if you are a child Etc. then they do three rounds of 15 minutes each separated by 2 minutes during those 2 minutes they take a cold shower where they cool down in some way.

They don't soak in a cold bath, but they refresh themselves with a cold shower and they do it three times, that's one session, they do 10 sessions, those sauna sessions were spaced out by at least a few days and the whole experiment means all 10 sessions. They were completed within a 3-we period and then a bunch of things were measured like how many white blood cells and immune cells were deployed after the first session versus the third versus the eth versus the 10th and so on, as well as The levels of cortisol and inflammatory markers are many different things measured in this study.

This is what we know. Sauna baths, as they call them, resulted in a statistically significant increase in cortisol concentration afterfrom the first and the tenth sauna session, okay, you always go to the sauna and you get an increase in cortisol. We know that because the heat is a stressor again, don't think about the heat, oh, you're just relaxing in that place. It's so nice that you get a cortisol response. Cortisol is a glucocorticoid stress hormone, as it's sometimes called, which can be a good thing if it triggers other things, like increasing the activity of the immune system, and in fact, that's what they observed later. and here.

To paraphrase after Saab's first and tenth baths, they witnessed an increase in lucite count. Lucaites are a particular type of innate immune system cell; However, only after the last sauna session did this change reach statistical significance in the trained group, so what they observed was that athletes who are trained are accustomed to being in very hot conditions due to their athletic training, the People who are not trained in athletics are not used to the fact that there are many different ways to look at this data, but the simplest conclusion is that if you are already very adapted to the heat because you sauna regularly or exercise regularly, then a further stimulus will be needed. stronger or more sauna, whether for longer, hotter or more frequently, to get the types of increase in innate immune response compared to someone who has never done it. sauna that you don't exercise regularly and that makes sense, if something is not stressful for you, you are not going to get the stimulation of that innate immune response and the general conclusion of this study was that I think if you feel a little bit down or if you are just Trying to keep colds and flu at bay, make a regular practice of entering the sauna for three 15-minute rounds separated by a two-minute cooldown—you don't necessarily have to. take a cold shower or cold bath in between, although I don't see why you couldn't or didn't want to, you could also just get out of the sauna and be outside and then come back in or maybe do something. closer to what has been shown in other studies exploring the relationship between heat exposure and immune response, which is doing two 20-minute rounds or one 30-minute round in the sauna, whatever you can do. safely and comfortably, keep in mind that safety is key.

Don't hurt yourself, I say this not to protect myself but to protect you, that the sauna is an effective way to increase the activity of the innate immune system, it increases Lucy levels, yes, it increases cortisol levels, but in a way which promotes the activity of the innate immune system however and here we return to exactly the same thing we said about exercise if you already feel very exhausted you feel a kind of heaviness in the body you don't feel well you are starting to get some colds no Don't go into a very hot sauna, but to keep colds and flu at bay, be sure to do three 15-minute rounds in the sauna between 176 degrees and 210 degrees, whatever you can safely tolerate, taking those two-minute breaks in between, maybe take a cold shower. or a cold shower, maybe just stay outside the sauna in the middle, if you're feeling too strong, jump in the charcoal for a minute, two minutes in between, not necessary but you could certainly do it and then go back in and then repeat or just do it. a 20 minute session or a 30 minute session, all of which have been shown to promote immune system activity Nate, however, I realize I said this before, but I feel like I need to say it again, especially for you hardcore exercisers or people I really feel like I can keep going if you are already sick and have the symptoms of a colder flu you want to limit the amount of stress on your body you want to lie in bed and sleep if you can't sleep you want to relax, you don't want to exercise, You shouldn't exercise, not only can you make other people sick by going to places where you exercise, but even if you exercise at home or in total isolation you are going to prolong the duration of that illness because there are many reasons to continue slowing down the circulation and allowing your innate and then adaptive immune system to kick in and fight those infections will allow you to get back to a regular regimen of exercise and work much quicker than you otherwise would.

The case, if you were to move on, okay, now we come to the part of the discussion that I think many people are probably anticipating: what can be taken to reduce the chance of getting a colder flu or shorten the duration of one? colder flu? and I actually made a call on social media. I asked the question on Instagram and on I got thousands and thousands of responses, however, many of those responses converged on a few common things, like taking garlic. I heard, for example, that some people chew a clove of raw garlic every day during the winter.

I've heard about people taking fermented garlic. Some people swear by eonia, some people swear by eonia, vitamin C and zinc. There are now too many compounds in the medical and wellness literature to cover them all, so I'm going to highlight a few that I think are especially interesting and that have been shown in the reviewed science to be potentially useful, some of them you already know and I think some of them will be surprising or at least new to you. First, let's consider what most people believe is a A very effective way to speed up colds or flu is to make them last less time than they would otherwise, perhaps even preventing colds or flu, the most important is vitamin C, we hear all the time antioxidant vitamin C I grew up in an area where the Noel prize winning chemist, Lonus Pauling, who was a fan of vitamin C, took many, many grams of vitamin C every day, used to tout the benefits of vitamin C, here's the deal, there is some evidence and frankly it's not very good, that points to the fact that taking 6 to 8 grams, that's 6,000 to 8,000 milligrams of vitamin C per day, is That is, a lot of vitamin C each day can perhaps delay the onset of a cold or shorten its duration, so we are talking about very high doses here. and it is not a very strong effect, I should mention that for most people who are not used to taking a lot of vitamin C, if they took 6 to eight grams of vitamin C in capsules, powder or pills, they would probably experience some discomfort significant gastric upsets, some people can increase to that level or take it with food in a way that does not cause gastric upset, but many people will experience gastric upset.

Much has been said about vitamin C and its other potential functions in our physiology and I don't want to touch on those topics now because it may have some interesting functions in other aspects of our physiology, but I must say that in reviewing the literature on vitamin C I found a recent article, which was published in 2023 and the The title of this article is retraction of an extra dose of vitamin C based on daily supplementation to shorten the common cold. A meta-analysis of nine randomized controlled trials. What is this article that was recently published? Why is retraction the first word in the title?

Well, it turns out that the meta-analysis of nine randomized controlled trials that showed a small but significant improvement in cold and flu outcomes or a reduction in the likelihood of getting colds and flu, that study was retracted and retracted based on multiple cases of an error where the placebo groups had been counted twice in the trials more than in the two intervention arms, so there were some serious errors in the data analysis in that meta-analysis. That's not to say that vitamin C has no benefit in reducing the chance of colds and flu, but I must always say that "If you are getting sufficient amounts of vitamin C from your food intake, you may also get some your vitamin mineral supplement or if you take a basic supplement like Ag1 or something similar, you are almost certainly getting enough vitamin C, it doesn't seem like taking high doses of vitamin C would put 6 to 8 grams of vitamin C in the range.

High doses will be effective in treating or preventing colds and flu, so more data may be coming in the near future, but vitamin C probably isn't a very good investment if you take it solely for the purpose of improving your system's function. immune and prevent colds and flu now. What about vitamin D? We hear a lot today about the importance of having sufficient levels of vitamin D. Ideally, everyone should measure their vitamin D levels through regular blood tests. I have blood tests every 6 months. I find it incredibly informative. I wonder what's going on under the hood in ways I could never know where I shouldn't get that test, but I realize those tests come at a cost and not everyone can afford them.

I think most doctors would agree that supplementing with anywhere between a thousand and 2,000 IU of vitamin D per day is probably safe for most people and will buffer that level of vitamin D in your system so that it is little They are likely to be deficient and far exceed what is safe in the body, however, there are people who need higher levels of vitamin D supplements to achieve sufficient amounts of vitamin D for their mental and physical health. I mean, vitamin D is involved in many different processes in the brain and body. It is now clear that people who take vitamin D-deficient, so these are people whose vitamin D levels have been measured, often have diminished immune system function and are more prone to acute respiratory tract infections.

There is a very extensive and very interesting review titled Vitamin D supplements to prevent acute respiratory tract infections, systematic review and meta-analysis of data from individual participants this is a beast um I read it all very, very interesting, many studies, the exact conclusions of a large review like this of 20 randomized control trials is a bit complicated, I mean, they concluded that vitamin D supplementation reduced the risk of acute respiratory tract infection among all participants; however, the degree of prevention was small to moderate in some cases. However, they noted that only because people with low levels of vitamin D tend to get colds and flu more often. that people who don't do it doesn't necessarily mean that vitamin D deficiencies are the reason for this, for example, we know that people who are regularly exposed to sunlight and as everyone knows, I'm a big proponent of let sunlight reach your eyes as soon as possible during the day after you wake up and, if it's cloudy, spend even more time outside if you can and if you can't access sunlight for any reason, perhaps invest in a 10,000 Lux light tablet, you can find them online at reasonable prices. you know, it costs between $100 and $200, in some cases, sunlight sets in motion a lot of different things, including increasing the amount of vitamin D in your system, but also a lot of other things, increases in the cortisol, increases in dopamine, increases in serotonin that cascade to and relate to improved immune system function, so what's the takeaway here?

I think for most people taking supplements with between 10 and 2000 international units of vitamin D it's probably safe; However, if you need more vitamin D, you won't know unless you take a Vitamin D test, that is, it measures the amount of vitamin D in your bloodstream, and in fact, some people need between 5,000 and 10,000 IU of the vitamin. D per day, but you don't want to overdose on vitamin D, that is, if you already have high enough levels. of vitamin D in your system and you are getting enough sunlight, then taking 10,000 or more international units of vitamin D could be harmful.

I think it's fair to say that based on the meta-analysis and review I mentioned a moment ago and the other articles. I was able to deduce that vitamin D itself is unlikely to be the only protector against colds and flu, but it's probably good to include in your overall nutrition and supplementation toolkit if your goal is to keep your innate immune system fighting. colds and flu, other things that maybe support the innate immune system will be, as I mentioned earlier, things that support the gut microbiome, so those low sugar fermented foods maybe a probiotic capsule prebiotics maybe something like sports greens ag1, although it could certainly be achieved. sufficient microbiome support from foods if you are careful and intentional with the foods you select Now the other compound or substance that we often hear about in the context of colds or the flu is eonia eonia is a compound that has been proposed toboosting the immune system works now when you look at the data and explore what taking eonia tinctures or other forms of eonia actually does to prevent colds and flu, the answer that comes back is not much, if anything now, is taking eonia dangerous, probably not, however, it has been demonstrated.

In some studies, people taking eonia regularly at high doses can potentially impede the function of their innate immune system, meaning reductions in white blood cell count, reductions in those natural killer cells, so my suggestion would be if you love absolutely to eona for anything. For the reason that you are convinced that it helps you, you reserve taking it when you start to feel a little run down or maybe only in the winter month, not plural, but in the month when you are most prone to colds and the flu. infections, but then don't take it continuously throughout the year and certainly not for more than four weeks at a time, but again, if you do, know that there is actually no solid scientific data to support the use of eona, on the contrary, there.

There is pretty good data supporting zinc supplementation as a way to combat colds and flu, particularly colds. Now here doses really matter. It has been shown that taking less than 75 milligrams of zinc in supplement form to try to impact your chance of getting or shortening a common cold is not going to work, you need to take 100 milligrams or more and now 100 milligrams or more of zinc to Some people will experience gastric upset if taken on an empty stomach. In fact, I have done it. the mistake of taking I think it was 50 milligrams of zinc on an empty stomach and I felt very nauseous I didn't feel well so don't take zinc on an empty stomach and if you're trying to cut short a colder flu you think you already got or are trying to To keep a cold or flu at bay because you've been around people with a cold or flu or you're just worried about taking 100 milligrams of zinc, maybe split it into two doses of 50 milligrams each. or perhaps 100 milligrams at once, but making sure you take it with at least a moderate or full meal could certainly be advantageous.

Keep in mind that people over 65 are perhaps those who need to supplement zinc the most. Note that children, i.e. people under 15 years old, should probably not supplement with too much zinc as it can be problematic and certainly pregnant women should have spoken to their doctor before supplementing with zinc, so fact, every time you go for a drink, whether you are there or not. Pregnant young, elderly or not, you should consult your doctor before taking anything or eliminating anything from your health protocols. One of the most interesting aspects of zinc supplementation that I could find in the literature is a three times faster recovery rate for people who already caught a cold, so in this study people didn't take 100 milligrams, but the dose was pretty close: they took 90 milligrams per day of zinc acetate and experienced a three times faster rate of recovery from that cold compared to people who weren't taking the zinc now, of course, there could be other factors as well, but The study was quite convincing, given that zinc has a fairly low cost, given that it is generally safe for most people and the fact that if taken with food it does not cause any discomfort supplementing with Inc at a level between 90 and 100 milligrams per day, probably no more than 120 per day, seems like a logical way to avoid colds and flu and reduce the duration of a cold or flu in case you get one now.

To be very clear, I've been talking about colds and flu together, treating them more or less as the same thing, some of that is a matter of time and simplicity, most studies showing a benefit from zinc. There are studies showing the benefit of zinc for treating or speeding up colds, not specifically for the flu. However, I consulted with some doctors, one of whom is an expert in this area and he told me that he saw no reason why I wouldn't take it. Zinc, if you had the flu, there's no reason to think it would introduce any kind of increased risk, but check back with your doctor before taking or eliminating anything from your supplement regimen.

Now many of the compounds we are discussing are somewhat conventional. in the sense that I think most people have probably already heard of them, perhaps the most esoteric sounding one so far is eona, which we established is probably not very helpful for colds or the flu, but we've been talking of vitamin C. zinc, vitamin D, making sure you get sunlight, supporting your microbiome, etc., a compound that I guess most people may not have heard of, but is very interesting, actually , I have taken it before and stock it in my supplement cabinet in case I feel like I am suffering from something is it acetylcysteine ​​or Knack what is Knack Knack is a precursor to glutathione what is glutathione glutathione is the master antioxidant involved in reducing the so-called reactive oxygen species that accumulate in cells that are metabolically very active reactive oxygen species accumulate further in cells that are under stress or in a body that is under stress and also has the property of reducing reactive nitrogen species Reactive oxygen and reactive nitrogen species increase significantly under conditions of infection and having sufficient levels of glutathione is a good thing now.

Netal is used in certain clinics abroad and in the US as a way to treat cystic fibrosis because it is also a mucolytic and cystic fibrosis is the buildup of fluid in the lungs and a mucolytic substance. it's something that loosens mucus and allows it to flow more easily from different cavities of the body, including the lungs, nasal passages, and sinuses, and in fact, last winter, unfortunately, I came down with a cold, which I told you about once every 18 to 24 months. I caught a cold and it was quite unpleasant 1. At first I felt very congested. I thought it was an ear infection pretty quickly.

I realized I had a cold and felt so congested I wasn't sleeping well and they suggested that. To take acetylcysteine, I ended up doing it at a dose of between 600 and 900 milligrams three times a day, so it was a 600 to 900 milligram capsule, depending on the brand. I bought many different versions of this on the market. I took it in the morning at the end of the morning and in the afternoon and it's actually a powerful mucolytic, the mucus just starts coming out of you. You better have an extra box of tissues on hand and that greatly relieved the pressure in my sinuses and the reason I liked using Knack is because I have actively avoided using decongestants that can be bought over the counter, most of them.

Decongestants are of the alpha one agonist variety. What is an alpha 1 agonist? Causes constriction of the vessels. Constricting the vessels may be beneficial in preventing some of the intense congestion that occurs when you have a sinus infection or a cold or flu, but then when those decongestants wear off, you tend to have a rebound increase in congestion and It's a really painful headache, etc. Also, some over-the-counter decongestants can be habit-forming, not necessarily addictive, but they are habit-forming and don't seem to have any other positive health benefits, so I prefer not to take decongestants if I can avoid them.

I had a very good experience with Knack and using Knack and acetal cysteine ​​as a decongestant and also as a way to prevent colds and flu is not a completely new idea; in fact, there is an article dating back to 1997 titled Attenuation of Flu-Like Symptomology and Enhancement of Cell-Mediated Immunity with Long-Term Anical Cinee Treatment. Now, in this study, they looked at people who were taking 600 milligrams of anal cysteine ​​twice a day for 6 months and what they observed is that people who took anal cysteine ​​were significantly less likely to get the flu. Now this is just one study, there have been a few other studies done and unfortunately there isn't a huge amount of research looking at Knack as a preventative for colds and flu, but the data in this article is interesting enough and it compelled me. to find a doctor who I noticed was answering my questions on social media about What do you use for colds and flu?

When I posted that, as I mentioned, I got thousands of responses on both Twitter X and Instagram and one doctor in particular who has a YouTube account, his name is Dr. Schwell, he's a doctor. He works in an INT Ive care unit and deals with many patients who have different strains of flu. In fact, he was the one who pointed out to me that there seems to be a good amount of H1N1 flu viruses circulating this year. and remember that the H1N1 flu virus, while not deadly to everyone, can be quite serious in some people, so we want to be vigilant and try to avoid getting H1N1 if we can.

I spoke with Dr. Schel, he was very generous. with his knowledge of anical cysteine, he recognized and I will acknowledge again here that it would be great to get more randomized control trial data on netal cine, but we talked about this article from 1997 and he mentioned that he and other doctors who are forced to be in The hospital seeing patients all winter and year-round are bombarded with cold and flu exposure all the time, which means he and some of his colleagues deliberately take cysteine ​​anical as a preventative to try to reduce the chance of catching colds. and flu, and while we don't want to put too much weight on any one study or data, which is what we're describing when I tell you about a doctor who told me this or what I did and experienced, I think it's worth paraphrasing the study I mentioned before that NAC prevented the symptomatic forms caused here that they talk about. the ah1n1 influenza virus quite efficiently since the vast majority of infected subjects in the placebo group (79% developed clinically apparent disease versus only 25% in the knat group in other words, approximately 80% of The people in the study who did not take acetylcysteine ​​got the flu, while only 25% of the people who took anical cysteine ​​got the flu, so it's a pretty dramatic difference and certainly the fact that anal cysteine ​​has been shown to increase glutathione, which is its main mechanism of action as far as we know and the fact that it increases in glutathione are generally healthy and good for us and the fact that anical cysteine ​​is still legally available without a prescription in the US, at less so currently, a few years ago, as you may have heard that the FDA called for the removal of over-the-counter Netal Cysteine ​​-over-the-counter sales I should point out were based on the fact that certain supplement companies were making claims about. netal cine as a hangover treatment and they made a bunch of other claims for which there was no real data, but because the FDA was effective in getting those companies to stop those claims Andor because of the advocacy groups that worked very hard to try to stop keep Netline available for over-the-counter sales, as far as I know, at least until before recording this episode, netal cysteine ​​is available for sale. without a prescription so whether or not you decide to use netal cysteine ​​as a preventative and again the dosage is about 1200 milligrams per day divided into two different doses of 600 milligrams each or if you decide to take anal cysteine ​​like I did which was not like preventative, but once I had a cold I couldn't fight it, apparently I caught a cold and decided to take 900 Mig three times a day avoiding that intake close to sleep because it interrupted my sleep if I took it too close to sleep because of the way the mucus flowed so easily.

You know, essentially. I know it sounds gross, but it felt like it was filling the back of my throat, the so-called postnasal drip, but it felt like a postnasal waterfall and I decided to restrict. my intake of cysteine ​​anical until earlier in the day only and of course there is the third option which is that you choose not to take cysteine ​​anical until more randomized control trials are published or not take cysteine ​​Cal at all because it is the kind that's okay with a little sleep a hot shower a good meal some chicken soup maybe some garlic who knows maybe you have other tools and techniques that you like you like that lemon ginger tea Etc.

Maybe that's all you need and if that's all you need and that's all you need to deal with a cold or the flu, be my guest. I'm certainly not here to convince anyone that you have to take a certain supplement, but I felt I would be remiss if I didn't cover what they are. generally known as so-called preventatives and treatments for colds and flu, things like zinc, vitamin D, vitamin C, now we know that, unfortunately, vitamin C gets a, you know, probably a Dminus or an F, at least based on current data, but there are these other things like zinc and potentially a cysteine ​​acetal that may be beneficial in shortening the duration of colds or flu and maybe even helping us avoid colds or flu due to complete.

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