How to Prevent & Treat Colds & Flu

welcome to the huberman Lab podcast

where we discuss science and

science-based tools for everyday

[Music]

life I'm Andrew huberman and I'm a

professor of neurobiology and

Opthalmology at Stanford school of

medicine today we are discussing colds

and flu we will talk about what a cold

really is and what a flu really is in

terms of how they impact your brain and

body and of course we will discuss how

to avoid getting colds and flu there are

indeed some excellent science supported

techniques to avoid getting colds and

flu but of course it is impossible to

completely avoid ever getting a colder

flu in your lifetime so we also discuss

how to more quickly get over a colder

flu should you happen to catch one so

during today's discussion I'll talk

about the immune system I'll give you

some mechanistic understanding of how

your immune system works and I promise

to make that discussion accessible to

everybody regardless of whether or not

you have a background in biology and

with that understanding of how your

immune system works you will be in in a

much better position to understand which

tools that is which protocols to

implement should you be exposed to a

colder flu or if you are trying to get

over a cold or flu more quickly than you

would otherwise you'll learn about some

potent behavioral tools for bolstering

your immune system and we will also

discuss various compounds that you might

consider taking to enhance the function

of your immune system to ward off or

treat colds and flu I will also be

dispelling a number of common myths

about treatments for the common cold C

and for the flu there are oh so many

ideas out there about what one could

take or do in order to avoid getting the

colder flu or more quickly get relief

from a colder flu however many of those

are pure myth there's just no sence to

support them and indeed there's some

science that counters those ideas but

the good news is there are indeed

science suppored behavioral protocols

and compounds that one could consider in

order to avoid and treat colds and flu

before we begin I'd like to emphas ize

that this podcast is separate from my

teaching and research roles at Stanford

it is however part of my desire and

effort to bring zero cost to Consumer

information about science and science

related tools to the general public in

keeping with that theme I'd like to

thank the sponsors of today's podcast

our first sponsor is ju ju makes medical

grade red light therapy devices now if

there's one thing I've consistently

emphasized on this podcast is the

incredible role that light can have on

our biology and of course I'm always

telling people that they should get some

sunlight in their eyes as soon as

possible after waking on as many days of

their life as possible for sake of

setting circadian rhythm daytime mood

focus and alertness and improve sleep

now in addition to sunlight red light

and nearin red light has been shown to

have positive effects on improving

numerous aspects of cellular and organ

Health including faster Muscle Recovery

improved skin health and wound healing

even improvements in acne or that is

removal of acne reducing pain and

inflammation improving mitochondrial

function and even improving Vision

itself what sets ju apart and why it's

my preferred red light therapy device is

that it has clinically proven

wavelengths meaning it uses specific

wavelengths of red light and near

infrared light in combination that

trigger the optimal seller adaptations

personally I use the handheld ju every

day the handheld ju is about the size of

a thick piece of toast and I also own a

ju panel that allows for full body

exposure and I use that one

approximately five times per week for

about 10 to 15 minutes per session if

you'd like to try ju you can go to ju

spelled

jv.com huberman again that's jv.com

huberman for this month only January

2024 juv is offering exclusive discounts

to huberman lab listeners with up to

$500 off select ju products again that's

ju spell

jv.com huberman to get up to $500 off

select ju products today's episode is

also brought To Us by Helix sleep Helix

sleep makes mattresses and pillows CL

that are tailored to your unique sleep

needs now sleep is the foundation of

mental health physical health and

performance when we are sleeping well

and enough mental health physical health

and performance all stand to be at their

best one of the key things to getting a

great night's sleep is to make sure that

your mattress is tailored to your unique

sleep needs Helix sleep has a brief

two-minute quiz that if you go to their

website you take that quiz and answer

questions such as do you tend to sleep

on your back your side or your stomach

do you tend to run hot or cold in the

middle of the night maybe you don't know

the answers to those questions and

that's fine at the end of that

two-minute quiz they will match you to a

mattress that's ideal for your sleep

needs I sleep on the dusk D mattress and

when I started sleeping on a dusk

mattress about 2 years ago my sleep

immediately improved so if you're

interested in upgrading your mattress go

to helixsleep.com

huberman take their two-minute sleep

quiz and they'll match you to a

customized mattress for you and you'll

get up to $350 off any mattress order

and two free pillows again if interested

go to helixsleep.com huberman for up to

$350 off and two free pillows today's

episode is also brought To Us by Roa Roa

makes eyeglasses and sunglasses that are

the absolute highest quality I've spent

a lifetime working on the biology the

visual system and I can tell you that

your visual system has to contend with

an enormous number of challenges in

order for you to be able to see clearly

Roa understands those challenges and has

designed their eyeglasses and sunglasses

accordingly so that you always see with

Crystal Clarity Roa eyeglasses and

sunglasses are designed with a new

technology called float fit which allows

them to fit perfectly and not move

around even when you're active in fact

whenever I'm wearing my Roa eyeglasses

or sunglasses I usually forget that I'm

wearing them I happen to wear Roa

eyeglasses at night when I drive or if

I'm reading at night and I wear Roa

sunglasses during the daytime if it's

very bright especially if I'm driving

into sunlight if you'd like to try Roa

eyeglasses or sunglasses you can go to

roka.com that's

r.com and enter the code huberman for

20% off your first order again that's

r.com and enter the code huberman at

checkout okay let's talk about the

common cold first off no unfortunately

today I cannot tell you the cure for the

common cold because indeed there isn't

one one interesting question however is

why don't we have a cur for the common

cold and the reason is that the cold

virus as it's referred to is actually a

bunch of different viruses some colds

are caused by one what's called serotype

of the virus other colds are caused by a

different serotype of the virus there

are over 160 different types of what

people call the cold virus now cold

viruses fall under an umbrella of a

general category of viruses called Rhino

viruses you can remember that easily

because rhino sounds like Rhino horn the

rhinoceros horn which is of course in

the center of the Rhino's face which is

where your nose is and the cold almost

always causes some degree of nasal

symptoms in humans it's either runny

nose or sneezing or stuffed up nose or

sometimes unfortunately all three now

the reason we don't have a cure for the

common cold is that all of those

different serotypes of the cold virus

mean that the virus itself has a

different shape on its outside and as a

consequence even if you've been exposed

to a cold and you've developed

antibodies against that cold virus the

next cold that comes along very likely

has a different shape and therefore your

body's antibodies to the cold virus it

combed successfully before can't latch

onto and defeat that next different

serotype of the cold virus now a little

later I'll talk about the immune system

and how those different antibodies are

generated but for the time being

understanding that there are a lot of

different types of cold viruses explains

first of all why we don't have a cure

for the common cold but also why you can

get multiple colds within a given year

or even within a given season because

even if you develop antibodies against

one serotype of the cold virus a

different serotype can come along and

you can get sick again with that new

serotype of the cold virus so how do you

catch a cold now one of the problems

with the cold virus being called the

cold virus and the fact that indeed

there are more cold viruses present and

transmitted between humans in the cold

winter months of the year is that people

generally assume that it is the cold

temperatures outside that actually give

you a cold virus and that is simply not

true however what you heard as a kid if

your mom most likely but maybe your dad

said hey don't go outside without a

sweater or jacket on you're going to

catch a cold or you're going to catch

cold you know has ated this uh this myth

that the cold temperatures themselves

are the cause of catching a cold virus

and that's simply not true the virus

that we call the cold virus is spread by

breathing or by sneezing or by people

sneezing or coughing or breathing onto

their hands and then touching surfaces

and then other people touching those

surfaces and then touching most likely

their eyes in order to self- infect now

we're going to get into the details of

how far the virus can spread with a

sneeze how long it can survive on the

hands Etc but for the time being know

this the cold virus is a pretty stable

virus in that it can survive on surfaces

nonhuman or human surfaces meaning skin

or on a table or on a glass or on a door

handle for up to 24 hours so for all you

hypochondriacs out there I probably just

gave you a little spike in cortisol and

for you non- hypochondriacs I hope what

I just said cues you to the fact that

just avoiding people who are sneezing

and coughing is not sufficient to avoid

getting colds and flu However the fact

that a cold virus is Alive and Well on a

given surface let's say on a door handle

does not mean that if you touch that

door handle that you will necessarily be

infected with that cold virus and that's

because your skin actually provides an

excellent barrier against most viruses

and bacteria your skin also includes a

lot of antiviral substances on it even

if you haven't put any of that you know

alcohol stuff or the hand sanitizer

stuff on your skin is a very important

barrier component of your immune system

we're going to talk about that a little

bit later but if somebody has a cold and

they happen to perhaps you know wipe

their nose or sneeze into a tissue

hopefully into a tissue and then discard

that

tissue the cold virus particles are

extremely small how small well most of

us are familiar with thinking about

centimeters or inches if you think about

a millimeter being 1/ 100th of a cmet

well you can take a millimeter and you

can divide that up into a bunch of

little slices also such that you get the

Micron the Micron is 1

1,000th of a centimeter and if you want

to get a sense of how thick or thin that

is the side of a credit card the little

thin side of a credit card is about 200

microns thick so if you set your credit

card flat on a table and then you look

at it from the side that tiny tiny thin

little Edge that's about 200 microns the

cold virus is made up of particles that

are probably in the range of about five

microns or so so it's extremely small I

mean the cold virus therefore with a

good sneeze or even a light sneeze can

spread really far now the good news is

those particles are relatively heavy

they don't tend to mist about in the air

for very long they tend to fall down

onto the ground or onto surfaces but as

I mentioned before they can survive for

a very long time on those surfaces so

should you touch your hand to a door

handle or table or shake the hand of

somebody that has cold virus on their

hands either because they themselves

have a cold or they contacted somebody

else had cold virus and it somehow

landed on their hands just cu the other

person sneeze all these scenarios are

very

realistic that cold virus will not

infect you unless it can get inside of

your body and one of the primary entry

points of it getting inside your body is

via the Eyes by wiping that cold virus

on your eyes now you may think okay I'm

just not going to touch my eyes but a

little bit later we're going to talk

about a study that shows that almost

always indeed almost always when you

meet somebody new you touch your eyes

and the frequency of people touching

their face that is the region of the

face around the eyes and their eyes

throughout the day is extremely high so

this is one of the primary routes by

which the cold virus is transmitted from

one person to the next but of course

there's also the route that we're all

familiar with which is the person that

is sneezing or coughing or blowing their

nose into tissues and then throwing them

in the trash and not washing their hands

after each and every time they do that

so an important aspect of today's

discussion that we will get into once I

also present to you what a flu is and

how it differs from the cold is that

we're going to need to talk about what

stage of infection people are actually

contagious with the colder flu and

there's actually a lot of Mythology

about this in fact there's a lot of just

lying about this people will be coughing

or sneezing and they'll say oh yeah I'm

not contagious any longer 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 that you can't be

contagious until you have symptoms so

we're going to go through all the

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 in a little bit

but for the time being know that the

cold virus is very very small it can be

transmitted through the air it can be

transmitted via contact from skin to-

skinin contact and it can survive on

surfaces for up to 24 hours and when you

touch those surfaces or a person with

the cold virus most often the way it's

going to get into your body and infect

you such that you get a cold is by

touching your eye region although

touching other regions of your body can

also pass the cold virus into you for

instance the mouth and lips but that's

actually far less common so we'll get

into that in just a little bit now

different serotypes that is different

types of cold virus tend to create a

different array of overall symptoms such

that you know one cold might be a really

quote unquote bad cold others are more

mild some tend to induce more runny nose

others more stuffy head and a little bit

of a fever or in some cases a lot of

fever one thing that's important to

understand is that if people are going

to be infected by the cold virus they

tend to develop symptoms one to two days

after they were exposed to the virus now

the good news is if you are exposed to

the cold virus that doesn't necessarily

mean that you are going to catch that

cold virus that is if your immune system

can fight off that cold even if you've

never been exposed to that serotype

before then you won't actually have that

cold and you won't transmit it so put

differently it is is possible to avoid

getting a cold virus even if you've

never been exposed to that serotype of

cold virus and you happen to come into

contact with somebody who has that

serotype of cold virus or you touch a

surface of some object door handle Etc

that has particular serotype of the cold

virus on it and God forbid you then wipe

your eyes that doesn't necessarily mean

that you're going to get sick and a good

portion of today's episode is going to

focus on tools that are supported by

science that allow you to bolster your

immune system and greatly increase the

probability that even if you're exposed

to a novel serotype of the cold virus

that is one that's new to you that your

body's never seen before that you won't

get sick another thing to understand

about the cold virus is that you're

generally most contagious to other

people when you feel at your worst that

is when you're coughing and sneezing and

you got the stuffy head watery eyes and

so on but you can also be contagious to

other people when you are starting to

feel better that said most of the data

point to the fact that about 5 to 6 days

after you hit your peak of worst

symptoms or I guess we should say your

Nader the dip of worst symptoms because

it's such an awful state to be in you

are probably exiting the phase in which

you're contagious now I want to be very

clear that does not mean that if you've

had a cold for five or six days that you

are no longer contagious if you continue

to experience sneezing and coughing

watery eyes in the evening you're

feeling much worse first thing in the

morning you're feeling especially groggy

Etc well then you are still contagious

another way to frame this is you know

those people that continue to show up at

the gym and show up at work and they

tell you yeah I got this cold but I've

had it for a few days I'm no longer

contagious and they're wiping their eyes

and they're blowing their nose frankly

they don't know what they're talking

about they are basically a walking

talking breathing sneezing coughing cold

virus Vector a vector is a route for

passage of a virus so please if you are

sneezing if you are coughing if you are

still experiencing the symptoms of a

cold stay home stay away from other

people as much as possible and I realize

that some people simply cannot avoid

going to work or cannot 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're starting

to feel better but we're still

exhibiting symptoms that we're not

contagious that is pure myth it's simply

not grounded in fact now there's nothing

that could be done about that first day

or two after which we're exposed to a

cold virus where we are not not

experiencing symptoms and it's quite

possible to pass the cold virus on to

other people but I think that every

workplace every home environment every

gym every society would benefit greatly

if people who were sick with the cold

did not expose other people to that cold

virus as much as possible and indeed

this is a serious issue it's not just

about a few sniffles and watery eyes

there's an enormous financial and mental

health cost and physical health cost to

people getting the cold and it's not

just about people who are immune

compromised or elderly people what we're

generally referring to as the cold today

can be mild it can be moderate it can

also be very severe and it can

exacerbate other health issues that

people have and we'll talk about that a

little bit later and how to offset some

of those health issues okay so 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

virus so you've got your a type flu

viruses your B type type flu viruses and

your C type flu viruses and by the way

I'm saying flu viruses but of course I'm

referring to influenza but it's just

kind of Common Place nowadays to refer

to influenza as the flu similar to cold

viruses the different types of flu

viruses exist based on the different

types of proteins that they express on

their surface in fact in the news over

the last few years there have been a

number of different flu virus strains

that have been described according to

their surface protein character istics

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 viruses are

in that a category of flu 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 think it

probably originated in New York or

perhaps elsewhere but certainly not in

Spain killed anywhere from 17 to 50

million people depending on which

literature you read that's an enormous

number of people and it 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 actually it's 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

propagation of those flu viruses and

that is done through a number of

different approaches the best and most

reliable approach of course is to not

come into contact with somebody that is

carrying the H1N1 or any other type of

flu virus however based on the way that

the flu virus infects the body the way

that the symptoms emerge and the ways

that viruses propagate that can't always

be avoided one thing to know and I

consider this a fortunate aspect of flu

virus biology is that the flu virus

unlike the cold virus can only exist on

surfaces for for about 2 hours after

about 2 hours it tends to die off so the

flu virus is most typically passed by

human human contact or coming into

contact that is walking into a cloud of

somebody's sneeze that contains flu

virus or somebody's cough that contains

flu virus and yes it is possible that

shaking someone's hand could actually

introduce flu virus to your hand and

then if you wipe your eyes or I'll talk

about a few other portals of entry for

the flu virus and cold virus in a few

minutes can get into your body and

infect you and yet you can pick up the

flu virus from surfaces however that is

far less common than the flu virus

passing from human human contact now

there aren't as many different types of

flu virus as there are types of cold

virus and that's why there have been

attempts at making flu vaccines or

so-called flu shots I think most people

are familiar with the signs and

advertisements online and in the

workplace and school saying you know get

your flu shot this season the reason

that flu shots can exist at all is

because there are limited enough types

of flu virus present in a given year

that specific vaccines that is flu shots

can be generated against that particular

strain of the flu virus so how effective

is the flu shot and I want to be very

specific here when we say the flu shot

singular it sort of implies that there's

one flu shot that can combat all the

different types of flu and as you just

learned that is not the case so we

probably should be saying the flu shots

but just for sake of Simplicity when I

say the flu shot I mean the flu shot

that's given in a given flu season that

is directed at specific strains of the

flu because researchers have determined

that that particular strain of flu or

strains of flu are the ones that are

most abundant for that particular flu

season Studies have shown that getting

the flu shot reduces one's risk of

Contracting the particular flu that is

most abundant That season by about 40 to

60% but of course the flu shot is

completely ineffective at combating any

other forms of the flu virus and of

course colds or other types of upper

respiratory infections Studies have also

shown that taking the flu shot can

reduce the severity of one's symptoms if

they in fact get the flu anyway now

personally I don't typically get the flu

shot and the reason for that is that I

don't tend to go into environments where

I am particularly susceptible to getting

the flu I don't work in a hospital or

clinic I don't tend to interact with

large numbers of people on a daily basis

so for me I've opted not to get the flu

shot now that doesn't mean that I've

never contracted the flu as I mentioned

earlier I 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 you know at one point a very

high fever in one case but typically a

moderate fever and the usual symptoms of

malaise that we've been discussing and

I've managed to get over those without

having taken the flu shop pretty easily

now of course we also don't know that

those were actually flu despite the

distinct differences between the

symptoms of Cold and Flu most people

don't really know whether or not they

have a cold or flu so this is another

thing to think about when considering

whether or not to get the flu shot

ultimately because at least to my

knowledge most workplaces do not mandate

that people get the flu shot I could be

wrong about certain workplaces but my

experience is that most workplaces do

not mandate that people get the flu shot

when you take the flu shot you're really

hedging a bet you're hedging a bet

against the fact that you will be or not

be exposed to that particular strain of

flu virus that's most abundant That

season or strains of flu virus that are

most abundant That season and that the

flu shot that you're taking is directed

at those particular strains so again in

my case I don't tend to take the flu

shot but of course you need to make the

decision that's right for you for

instance if you have family members that

are immune compromised or you work in a

school or you think that you are exposed

to a lot of flu or you're concerned

about transmitting flu to any one

individual or group of individuals those

are all things that need to be taken

into consideration and of course speak

to your physician I will also say this

which is that I mentioned that I've

tended to catch colds or flu at a rate

of about once every 18 to 24 months and

when I say a cold or flu I mean a

serious one one that keeps me in bed

where I have a fever and I'm sweating

what I have done and I continue to do is

because I pay pretty close attention to

how well I'm sleeping or different life

events my different workouts Etc and I

put those into my calendar and I have a

short hand to do that so it only takes

about 30 seconds each day okay did this

work out it was kind of level seven out

of 10 intensity got good sleep last

night or poor sleep in know what good in

poor sleep is for me I mean that's about

the level that I'm charting these things

I have been able to go back and look at

the events preceding when I've come down

with a cold or flu again I don't know

whether or not it was a cold or a flu

but before I got sick and I have seen

for instance if I've ever done two hard

workouts in a day something I never do

any longer I've tended to get sick after

that if I've tended to do hard workouts

and then expose myself to cold

temperatures while traveling especially

traveling overseas that tended to

precede those colds or flu which again

for me are very seldom so it's a limited

data set this is entirely anic data

meaning related to my own history of

getting colds and flu but it's something

that I actually recommend people do

which is you know to pay attention to

when you first started getting symptoms

pay attention to when you got over a

given what you think is a colder flu and

then to look at what was happening in

the days before in that day I don't

think it's possible to do hyper precise

forensics on a colder flu right I mean

you could have gone into to the gas

station put your credit card in the

machine to you know grab a drink out of

the refrigerator and picked up a colder

flu from the handle of the refrigerator

or from the credit card machine or even

from the gas pump you simply don't know

however if you look at the pattern of

behavior travel sleep exercise sorts of

interactions you were having prior to

getting a bad cold or flu chances are

you're going to learn something

interesting and be able to avoid getting

a serious cold or flu at least to some

extent going forward and I've done that

I think fairly successful y because I

can tell you that the frequency or colds

or flu that I've come down with has

indeed been dropping from year to year

so where're as a decade ago I tended to

get colds or flu probably about once a

year and in some cases even twice a year

although that was pretty rare that

really expanded to about once every 18

months and then in the last five years I

think I've gotten sick uh two times

pretty badly with a colder flu and then

once with a kind of mild colder flu so I

tell you all that just as an example of

how you can start to think about how

your immune system interacts with

different types of behaviors different

types of situations such that you can

learn something about your immune system

and what's going to best protect you

against getting colds and flu going

forward which of course is a great thing

to do because we all think that we can

get out there be around people that are

coughing and sneezing we can go to the

gym when it's crowded and winter oh that

person over there is you know coughing

but I'm going to just you know stay a

few feet away no big deal and while I

don't want to turn anyone into

hypochondriacs that's how you get

infected that's how you get a colder

fluid and at the same time I don't think

anyone should you know get to the point

where they're afraid to go into a gym or

afraid to go to the workplace but I will

say once again if you're sick with a

colder flu if you are coughing sneezing

blowing your nose runny eyes and you're

walking into work or the gym or onto

public transportation and you're telling

people I'm not contagious you're lying

I'd like to take a brief moment and

thank one of our sponsors and that's ag1

ag1 is a vitamin mineral probiotic drink

that also contains adaptogens I started

taking ag1 way back in 2012 the reason I

started taking it and the reason I still

take it every day is that it ensures

that I meet all of my quotas for

vitamins and minerals and it ensures

that I get enough Prebiotic and

probiotic to support gut health now gut

health is something that over the last

10 years we realized is not just

important for the health of our gut but

also for our immune system and for the

production of neurotransmitters and

neuromodulators things like dopamine and

serotonin in other words gut health is

critical for proper brain functioning

now of course I strive to consume

healthy Whole Foods for the majority of

my nutritional intake every single day

but there are a number of things in ag1

including specific micronutrients that

are hard to get from Whole Foods or at

least in sufficient quantities so ag1

allows me to get the vitamins and

minerals that I need probiotics

prebiotics the adaptogens and critical

micronutrients so anytime somebody asks

me if they were to take Just One

supplement what that supplement should

be I tell them ag1 because ag1 supports

so many different systems within the

body that are involved in mental health

physical health and performance to try

ag1 go to drink a1.com huberman and

you'll get a year supply of vitamin D3

K2 and five free travel packs of ag1

again that's drink 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 virus that is you are

contagious about 24 hours prior to the

onset of first symptoms for you so that

means that you can be a flu viral Vector

even when you aren't having symptoms

that's just the unfortunate aspect of

these viruses they're very clever they

don't have brains but these viruses have

adapted to propagate from host to host

to host they have a drive to continue to

stay alive and to infect more host so

even though they don't have a brain they

have a sort of uh let's call it viral

intelligence and as I've said several

times now if you are still exhibiting

symptoms of the colder flu you are

contagious however with respect to the

flu you are most contagious during the

three days when you feel the absolute

worst when your fever is at its worst

we'll talk about how to deal with fever

a little bit later when you are coughing

and sneezing headache all of that when

that is at its peak that is when you are

most contagious so again I realize that

people can't always avoid contact with

other people you know you live under the

same roof sometimes caretaker is

interacting with the person that has the

cold or flu and I do want to remind you

something I said earlier which is just

because you come into contact with a

colder flu does not necessarily mean

that you will come down with that is be

infected by a colder flu whether or not

you come down with a colder flu is of

course dependent 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 like you

can't get eaten by a shark if you never

go in the ocean however the probability

of coming down with that cold or flu of

it getting past your immune system

barriers and infecting you is going to

be strongly dictated by the different

aspects of your immune system for which

there are three major aspects which

we'll talk about next and of course the

things that you do to bolster those

three aspects of your immune system okay

let's talk about your immune system and

I have to confess that even though I've

spent well over three decades being a

student of and a researcher of the

nervous system the immune system is oh

so cool and I say that because it has

this incredible elegance and logic to it

it basically consists of three major

lines of Defense there's a physical

barrier or rather a set of physical

barriers that exist between the organs

of your body and the outside world and

you're probably immediately thinking

skin and yes indeed it includes 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'll

talk about those in a moment then

there's a second line of defense which

is for any virus or bacteria or fungus

for that matter but today we're talking

about viruses colds and flu viruses any

viruses that get past the physical

barrier of your skin and the mucosal

lining of particular regions of your

body well then you have What's called

the innate immune system the innate

immune system is this very generalized

response system it's General in the

sense that it deploys a basic set of

neurochemicals that are not specific to

the particular virus that's made it into

your body so not only is it not specific

to a particular serotype of the cold or

a different type of flu virus but it's

not even discriminating between cold or

flu virus this thing we call the innate

immune system is a generalized response

system to go and combat viruses so it

could be a cold it could be a flu it

could be a bacteria it could be a fungus

it could even be a physical object and

your innate immune system responds by

saying okay let's go deal with this now

the third component of your immune

system is What's called the Adaptive

immune system and I alluded to this

aspect of your immune system a little

bit earlier the Adaptive immune system

is the aspect of your immune system that

recognizes because the innate immune

system told it that something has

infected the body at some level at some

organ or set of organs and there's an

emergency and the Adaptive immune system

goes in and in a very targeted way

figures out what sorts of proteins it

needs to produce that is antibodies to

combat that specific serotype of virus

okay so the immune system has a physical

barrier component and it's not just skin

some other things as well you've got

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 actually a

good opportunity for us to just take a

brief step back and realize that anytime

we're talking about our physiology

there's going to be a mechanical set of

features and there's going to be a

chemical set of features so right now

we're talking about the immune system

and the mechanical feature or the

physical feature of the immune system is

this barrier between the organs of our

body and the outside world and the most

obvious of those is the skin you are

contained in this bag of stuff that we

call skin the skin isn't just for

putting clothing on and for adorning

with jewelry or tattoos if that's your

thing watches Etc your skin is a living

organ in and of itself I think we're

most accustomed to think about the heart

and the lungs and the liver and the

Brain as organs of the body but the skin

is an organ of the body as well it has a

bunch of different layers of cells from

the outside to the inside actually the

skin cells themselves are made in the

deeper layers of the skin and they

migrate out towards the surface of the

skin and at the surface of the skin on

top of those cells and made by those

cells are different types of chemicals

that actually serve as antibacterial and

antiviral agents meaning if a cold virus

or flu virus or other type of virus

lands on the skin it can neutralize and

kill that virus so your skin is a very

important physical barrier against

viruses such as the cold or flu virus

getting into your body and infecting

other cells and tissues now your skin is

not contigous meaning there are holes in

it so let's think about those holes for

a second as we go from head to foot it's

pretty obvious that your eyes have these

two openings and those are openings in

your skin right as you open your eyelids

beneath there are your corneas the shiny

part of your eyes and a little bit

further back at the back inner lining of

your eyeball you have a very thin three

cell layer thick piece of tissue that we

call the neural retina and I say this

because the neural retina is actually a

piece of your brain so you have two

pieces 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's a very short distance between the

opening of 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 isn't far

away from those openings that we call

your eyelids so as a consequence on the

surface of your eyes those corneas the

shiny part of your eyes on the outside

there are a bunch of different chemical

features there are tears that are made

by your lacrimal glands but there also a

lot of antibacterial agents that

actively kill off stuff that could

potentially infect your body could make

it into your body maybe even into your

brain if you've ever woken up in the

morning and you have some crust on your

eyes and you look at that crust that

kind of yellowy stuff sometimes it's

yellow I know this is kind of gross

that's actually dead bacteria that your

eyes have successfully defeated during

your night's sleep so when you wipe

those away you're taking the casualties

of a war that you won during your

night's sleep and you're whisking those

away now as we descend a little bit

further down the face they're of course

the nostril openings and the nostril

openings tend to be kind of sticky right

they're moist sticky and warm right you

don't have to put your fingers up them

right now you just know they're moist

sticky and warm get your fingers out of

your nose please the mucosal lining of

your nose is actually a very important

substance that is sticky in order to

trap viruses such as colds and flu

viruses and then chemical components

within the mucosa lining can neutralize

them that's the best case scenario there

are of course scenarios in which the

cold or flu virus takes residence in

your mucosal lining and can make its way

back into your sinus passages and can

then infect other cells and tissues of

your body because the virus replicates

and spreads throughout the body and then

going a a little bit further down I

realize this is obvious you have your

mouth and what's really interesting is

that your mouth also has mucosal lining

which is sticky and it has chemical

components to neutralize incoming

viruses but we know that the type of

mucus and the type of bacteria that live

in your nose and mouth that by the way

are very healthy for you and encourage

healthy immune system function that is

act as ways to neutralize viruses within

your nose and mouth are very different

so your nose and your mouth may seem

similar at the level of okay well it's

warm and sticky in there there's mucus

but they are very very different tissues

in fact if you think about your mouth

it's this incredible structure that not

only lets you eat and breathe in and out

through although I suggest most people

be nasal breathers for most of the time

of their day and night if you can of

course sometimes you have to mouth

breathe but keep this in mind that you

have this big opening in the front of

your face and bacteria are getting in

there all day long viruses are getting

in there all day long and in most cases

you are successfully combating those

viruses and bacteria because the mucosal

lining of your mouth and your nose for

that matter and the microbiota those

little micro organisms that have taken

resonance in your nose and mouth are

helping to contribute to fight off

bacteria and viruses provided the

microbiota there are diverse and are of

the type you want which we'll talk a

little bit more about later and then

descending further down the body of

course there are other openings Into

Your 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 it is distinct in terms of

its physical makeup and its chemical

makeup from the mucosal lining of your

nasal passages and mouth and then of

course we have the rectum and anus which

is the outflow pathway of your

intestines which are

post-design and frankly there need to be

more data in order to really resolve

this but it seems like the primary entry

site for viruses to get into the body

tends to be the eyes or the mouth and we

can get into some of the reasons why

that would be so but if you think back

to our conversation about the way that

colds and flu exist in the world either

as aerosols or on surfaces of objects or

on surfaces of skin well then what I'm

about to tell you next will make it oh

so obvious why the eyes and the mouth

are the primary sites of for colds and

flu and if you keep that in mind there's

a good chance you can avoid a lot of

colds or flu that you would otherwise

catch okay so before I talk about the

important roles of the innate and the

Adaptive immune system in keeping colds

and flu at Bay I'll 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 most

often after you shook somebody else's

hand now why am I picking on you well in

fact I'm not I'm picking on all of you

and I'm picking on myself included

because there have been several studies

now primarily from Noam soel Lab at The

whitesman Institute showing that when

people encounter another person and they

shake their hand they either touch their

eyes or touch another region of their

face very close to the eyes or that they

touched their hand to their mouth now

there are a bunch of theories as to why

people do this there's the idea that

people are actually sniffing their own

hands

and in particular sniffing their own

hand more often after they Shake someone

else's hand as a way to detect what

chemo signals exist on the other person

not necessarily conscious smelling of

the other person's smell but rather some

sort of unconscious mechanism by which

we take the chemicals of the person we

come into contact with and we bring them

to our nose our eyes or in some cases

our upper lip and that our olfactory

system that is the neurons that exist

just behind the back of our nose are

processing that information and getting

all sorts of important information about

how stressed the other person is their

hormones uh whether or not we recognize

them the fact that they are different

from us that's right we are also

smelling ourselves all day long noom's

lab has shown this that people are kind

of walking around in their own odor

Cloud we tend to touch our armpits we

tend to touch different aspects of our

body yes and smell ourselves multiple

times throughout the day this is all

being done unconsciously I suppose some

people are doing it consciously and that

there's a lot of information about our

physiology and health and when we do

this after shaking somebody's hand that

there's a lot of information about the

other person's physiology and health

that our nervous system our factory

system and deep parts of our brain that

are involved in primitive type behaviors

but also some pretty sophisticated

behaviors are taking into account now

Noom soel was a guest on the hubin Lab

podcast I encourage you to check out

that episode if you have time it's a

fascinating Voyage into the olfactory

system and not just conscious smelling

or sniffing of things so we go oh that

smells good or that smells bad or that

person you know is somebody I want to

mate with or hang out with or avoid it's

also unconscious processing of so-called

chemo signals chemical signals but the

reason I'm bring up these studies now in

the context of colds and flu and how to

avoid getting colds and flu is as a

reminder that we are pretty much wired

to contact our own face with our own

hands at the level of our eyes nose and

upper lip and around the eyes very

shortly after we touch somebody else's

skin and if you are mindful of it you

can actually avoid bringing colds or flu

to your face now in doing so are you're

going to shortcircuit a bunch of other

important biological processes involved

in understanding what's going on in your

environment because you're not bringing

in those smells I suppose that's

possible but with respect to avoiding

colds and flu it seems like a pretty

good trade-off to me so the point that

I'm trying to make here is that in order

for you to catch a cold or flu that cold

or flu virus the little particles of

cold and flu virus need to make it into

your body and the primary entry sites

are eyes nose mouth and the primary

actions by which we bring colds and flu

viruses to our eyes nose mouth are by

touching other people or by touching

other surfaces that have colder flu

virus just to remind you cold virus can

exist up to 24 hours on a given surface

flu virus tends to die off after about 2

hours on a given surface and we're

bringing to our face we are literally

bringing the virus to ourselves so a

little bit more conscious awareness

about that fact means that you can

probably avoid colds and flu to some

extent how much well it's unclear it's

unclear because as you recall some

people have and are passing along cold

or flu virus prior to any symptoms and

of course it's possible that you can

walk into an aerosol cloud of cold or

flu virus even if a person isn't there

and you don't come into contact with

them but some conscious awareness of

these routes of path passage for the

colder flu virus I do believe can reduce

the probability that you will catch a

colder flu and of course I'm not

encouraging people to never touch touch

is an important part of social

connection and social bonding but if you

start to think about these portals of

entry for the cold and flu virus into

your body well then you you know perhaps

might think twice before you know

hugging someone kissing them on the

cheek during a time in which you're

trying to actively avoid getting the

cold or flu now I feel a little bit

funny about sharing this information

because again I don't want to encourage

will always be at you know arms distance

you know uh you know fake fist bumping

you know keeping a gap between them

again touch is an important component of

social connection but since today's

topic is colds and flu and how to avoid

getting colds and flu just like you

can't get eaten by a shark if you don't

go in the ocean there's a much lower

probability that you're going to get a

colder flu if you're not touching a lot

of hands and bringing those hands to

your eyes nose or mouth I suppose one

way around the sort of do I hug do I

shake hands thing is to just be

conscious of the fact that when you

shake somebody's hand that you're very

likely to touch your eyes or face within

the next 30 seconds or so and maybe you

end up being that person who puts some

hand sanitizer on your hands sometimes

that can feel a little awkward to do

that right in front of somebody you know

it's kind of sending a signal like hey I

don't want you to infect me but guess

what you don't want them to infect you

okay let's imagine that a cold or flu

virus makes it into your system it

breaches the physical barrier of your

skin and mucosal lining now you have in

mind all the different ways that could

happen and all the different ways that

could be prevented but we are starting

at a point here a hypothetical point

whereby that colder flu virus has made

it into your body your immune system has

an absolutely exquisitely sophisticated

way of knowing you versus other meaning

cells within your body that are of you

and cells of your body that are from

other organisms or viruses from the

outside world and when viruses such as a

cold or flu virus are detected in your

body your body might not even recognize

that it's a cold or flu virus it might

not even recognize that it's a virus at

all it just knows that this thing that's

in me is of other it's not me I've never

seen it before this is not me these are

not my cells these are not the chemicals

that I'm producing and your immune

system is amazing in that way and when

it occurs your innate immune system

launches a response what is that

response well first of all the response

is very rapid right colder flu makes it

into your body and your innate immune

system immediately or near immediately

launches an attack on that Invader or

Invaders because as soon as the virus

gets into your body it's going to start

replicating as quickly as it

can what

happens white blood

cells that your body produces will go to

the sites where those viruses are and

the by the way those viruses are

basically getting into cells of your

body and then hijacking the genetic

Machinery of those cells in order to

replicate within those cells and then

exit those cells and then go infect more

cells that's how these viruses work your

body's making white blood cells things

like neutrophils natural killer cells

macras these are what we call affector

cells that act as a kind of ambulance

system and go to the sites that those

viruses exist and the cells that they've

infected and start trying to physically

barrier them in and also use specific

chemical mechanisms to neutralize and

kill those viruses again anytime you're

think about biology think mechanical

features and chemical features of a

response now a key component of the

innate immune system is What's called

the complement system not complement

like oh you look very nice today but

complement okay the complement system

which exists in the plasma within your

blood these are chemicals in your

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 cell types of your immune

system such that those natural killer

cells go through the body and go looking

for the cells that have this eat me

signal on them and try and destroy those

particular cells the other thing that

urinate immune system does is that the

cells that have been infected and that

are undergoing damage remember they have

colder flu virus within them and they're

hijacking the cell or Machinery of those

cells and using it to produce their own

virus more of the virus and as a

consequence the genetic Machinery of

those cells is not able to do a bunch of

other things that it normally can do or

at least not as well well those cells

that are really hurting release a help

me signal and then in response to that

help me signal your immune system

releases what are called cyto kindes

things like interlukin 1 interlan 6

tumor necrosis Factor Alpha just fancy

nerd names for different types of

molecules that go to the site of

infection and try to help or assist to

remove that infection and they also Tred

to assist the repair of the cells that

have been infected by those viruses now

one of the mechanical or physical

consequences of these chemical signals

like Incan 1 Incan 6 tnf Alpha again

those are all cyto kindes being drawn to

a particular cell or region of cells

that have been infected is that it

creates some physical swelling of the

area it impacts the vasculature the

veins and capillaries that feed that

area and in response to they put more

blood there so you get some swelling or

you'll get in some cases the release of

histamines right we think of

anti-histamine drugs well histamines are

an aspect of your immune system they

move around in your body in these really

cool cells called masted cells Mas mass

cells and when the histamines are

released that area becomes kind of hot

and swelling it's what we call edema and

that whole area is marked as really a

sight just like a crash site on the side

of the road it's like hey we've got eat

me signals to get the debris and the bad

stuff out of here try to get those

viruses out of here we've got help me

signals to try and help the injured

cells just like you would try and help

people at a car crash and there's a

bunch of swelling so there's additional

blood flow sometimes there's some other

physical features as well now the

important thing to know is that the

innate immune system is very fast and it

is agnostic to the type of infection in

fact it doesn't even matter if it's a

bacterial physical fungal or viral

infection but it certainly isn't paying

attention to the exact serotype of cold

virus or whether or not it's an H1

influenza or another type of influenza

so way to think about the innate immune

system is that it is a very fast and

non-specific response to a viral or

other type of Invader now that's all a

bunch of biology but if you think about

it let's imagine a scenario where you go

to a party hang out the party you don't

see anyone coughing or sneezing but

maybe one person there has a cold virus

or they have a flu virus and they aren't

even aware of it they're not going to

come down with symptoms for another day

or so you talk to that person you shake

hands maybe touch your eyes maybe you

don't but you're exposed to that colder

flue virus you go home you go to sleep

you wake up the next morning you feel

fine and then sometime in the next

afternoon you know you start to feel a

little tickle in your throat or you

start to feel just a little bit of

fatigue or

malaise do you have that colder flu well

possibly okay we don't know for sure but

assuming that that cold or flu virus did

indeed make it into your system then

your immune system is starting to create

a set of responses that we talked about

a moment ago but it also tends to impact

things at the level of your brain such

that you kind of feel like you know I

don't feel quite right I feel like a

little bit I don't feel great 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 coming down

with a colder flu well technically yes

your inate immune system is deployed to

fight this foreign viral Invader but

whether or not you actually get a

full-blown cold or flu or put

differently how severe that cold or flu

infection is depends depends on whether

or not your innate immune system can

fight off that colder flu at the outset

and indeed there are many cases we

believe where you get exposed to a

colder flu it makes it into your body

but your innate immune system is

sufficient to beat it to fight it back

this is one of the reasons why it's so

important that if you're starting to

feel a bit under the weather and you

think you're coming down with a colder

flu that you do certain things in order

to make sure that your innate immune

system is both ready and that it can

launch a fullscale attack on that colder

flu virus we're going to talk about how

to do that a little bit later I'm not

trying to withhold it's just it's

important to understand that just

because the virus makes it into your

body doesn't necessarily mean that

you're going to get a full-blown cold or

flu and in fact that inate immune system

sometimes is sufficient to prevent that

colder flu from replicating enough that

you get the full-blown 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 of malaise what to do if you

just discover that oh you know that

person I was hanging out with at the

party the night before they're really

sick with a colder flu because there are

things you can do to increase the

probability that your innate immune

system can handle the battle

sufficiently such that you never have to

get to the next component of the immune

response which is the Adaptive immune

response I'd like to take a quick break

and thank our sponsor insid tracker

insid tracker is a personalized

nutrition platform that analyzes data

from your blood and DNA to help you

better understand your body and help you

reach your health goals now I've long

been a believer in getting regular blood

work done for the simple reason that

many of the factors that impact your

immediate and long-term Health can only

be analyzed from a quality blood test

now a major problem with a lot of blood

tests out there however is that you get

information back about metabolic factors

lipids and hormones and so forth but you

don't know what to do with that

information with inside tracker they

make it very easy because they have a

personalized platform that allows you to

see the levels of all those things

metabolic factors lipids hormones Etc

but it gives you specific directives

that you can follow that relate to

nutrition behavioral modifications

supplements Etc that can help you bring

those numbers into the ranges that are

optimal for you if you'd like to try

insid tracker you can go to insid

tracker.com huberman to get 20% off any

of insid tracker's plans again that's

insidetracker

tocomin okay so the third layer of your

immune system is your adaptive immune

system and this is an amazing aspect of

you okay the stuff we talked about up

until now the physical barrier the

innate immune system so so cool but the

Adaptive immune system is really a

mindblower the most important thing to

understand about your adaptive immune

system is that as the name suggests its

job is to create antibodies specific to

the very Intruder that made it into you

and infected your cells the very

specific serotype of cold virus the very

specific type of influenza such that you

defeat that virus but then in an amazing

way your adaptive immune system also

maintains a memory of that battle and

keeps within your body believe it or not

within a population of stem cells which

are cells that can rise to more cells

such that if you ever encounter that

same serotype of cold virus or same

strain of influenza again that your

antibodies can immediately neutralize

that colder flu virus the Adaptive

immune system has the ability to make

proteins that have a particular shape on

their surface that matches the shape of

the thing that your immune system is

trying to kill now the Adaptive immune

system has two basic phases in the first

phase the Adaptive immune system makes

these things called

immunoglobulins IGS and the

immunoglobulins come in different forms

there's IGG there's IGM there are other

types of IGS as well for sake of today's

discussion know that the initial

wave of antibodies that the Adaptive

immune system makes or of the IGM

variety and the IG antibodies can travel

to and latch on to the surface of the

colder flu virus and it matches it

pretty well it's not perfect but it

matches it pretty well think about uh

for instance a particular serotype of

cold virus or the H1N1 flu virus having

you know very particular Contour on its

surface the M approximates that Contour

such that it's better at fighting that

colder flu virus than is the innate

immune system but it's not a perfect fit

however the Adaptive immune system

doesn't stop with the production of

those igms the Adaptive immune system

takes that information about how precise

or imprecise that fit is between the IGM

antibodies and the surface of that

particular cold or flu virus and then in

an amazing way send signals back to the

stem cell populations in the bone marrow

and other tissues and then more

antibodies come out of the IGG variety

and the IG proteins are very specific to

the shape of that particular cold virus

or flu virus such that the Iggs then can

Define to and neutralize those viral

particles okay so when we talk about the

immune system we're talking about a

physical barrier that if it is

breached a cold or flu virus takes

residence and starts to replicate the

innate immune system launches a

generalized attack on that colder flu

virus and then the Adaptive immune

system kicks in usually a couple days

later first with the production of

antibodies that are pretty specific to

the particular virus that happened to

make it into the body and infect cells

but then there's a second wave of

production of antibodies and those

antibodies are incredibly specific for

that particular cold or flu virus and as

I mentioned earlier the Adaptive immune

system then acquires a memory of the

specific fit between a given antibody

that it made and the viral Invader and

the successful battle that those

antibodies waged on that Viral Invader

and that memory is maintained such that

if the next week or the next season you

encounter the exact same serotype of

cold virus or same type of flu virus

well then you already have antibodies

ready to be deployed sometimes the

antibodies continue to circulate in your

system sometimes you need to generate

more of them and the immune system is

that amazing it can actually send a

message back to that stem cell

population in the bone marrow or

elsewhere say Hey listen this virus that

we beat a few weeks or months or years

back it's back we need more antibodies

and boom your adaptive immune system

churns those antibodies out and kills

the virus now as a final point about the

immune system I've been talking a lot

today about cells traveling to and

killing viruses and sending signals eat

me help me Etc it's important to

understand that while cells can migrate

through the the body a lot of what we're

talking about here is the movement of

proteins through the vascular through

the blood system of the body but there's

another system that's very important for

all of this that's collaborating with

the vascular system and that's the

lymphatic system we don't have time to

go into a whole lecture about the

lymphatic system but suffice to say the

lymphatic system can pull stuff from the

blood such as viruses but also cells

that have been beaten up or cells that

have been eaten and are contained within

other cells such as macrofagos and it

can do some filtering of those different

cell types and it can produce its own

useful chemicals that then can be

reintroduced to the bloodstream in order

to help combat the infection now this

becomes very important when later we

talk about how specific forms

intensities and durations of exercise

can increase the ability for your innate

immune system to combat infections so

that your adaptive immune system perhaps

doesn't even have to get involved in the

battle because your innate system

handled it there are data to show the

exercise of sufficient intensity and

duration but not excessive intensity and

duration can recruit the lymphatic

system and recruit or increase the

activity of the innate immune system

even in the absence of an infection such

that if you go to that party and you

encounter that person with a colder flu

you can defeat that colder flu virus at

the outset and never have to deal with

making antibodies to that colder flu

virus at all okay so now you have a

fairly sophisticated biological

understanding of what colds are what flu

are and the way that immune system works

to fight off viruses like colds and flu

so with that in mind I think now is the

appropriate time to start talking about

what the scientific peer-reviewed

research says about how to allow your

immune system to function at its best

such that you can combat colds and flu

meaning if you are exposed to a cold or

flu that is if it breaches that physical

barrier of your skin and the mucosal

lining of your nose your mouth or it

gets into your eyes that you stand the

greatest chance of defeating that colder

flu at the the level of your innate

immune system such that your adaptive

immune system never even has to respond

to it by creating all those specific

antibodies now fortunately there are a

lot of different things we can do to

improve the function of our immune

system in fact I feel like anytime the

winter months roll around we start to

see the same list of things surface

online and in the press and I don't want

to diminish these things they are in

fact the Bedrock of maintaining and

enhancing the function of your innate

immune system so what are those well

some of these will be pretty obvious

things like getting enough

quality sleep each night we know for

instance that if you're sleep deprived

so especially if you stay up all night

but certainly even if you only get 50%

or 75% of your sleep requirement that

your innate immune system is going to

suffer it's not going to be as effective

at combating flu or colds in addition to

that we know that exercise of specific

type and specific duration and specific

intensity can serve to bolster the

innate immune system and we'll talk

about the specific exercise protocols

that can best achieve that we also hear

and it's absolutely true that we need

adequate nutrition if we are in a

caloric deficit for instance if we're

trying to diet through the winter months

which many people try to do that can

place our innate immune system in a bit

of a compromised state that said things

like intermittent fasting or even longer

duration fast have been implicated and

here I really want to underscore

implicated in brief improvements in the

function of the immune system however

extended fast or not eating enough

calories to maintain body weight for

many many days in a row can actually

compromise the function of the innate

immune system I'll go into this a bit

deeper in a moment and then of course we

hear about stress that we're all

supposed to regulate our levels of

stress not get too stressed and here I

have to put an asterisk next to those

statements because yes indeed chronic

stress meaning stress that continues day

after day after day or even short

periods of stress that impede our

ability to sleep at night can indeed

reduce the functioning of our innate

immune system however it's also clear

that short bouts of stress provided that

they don't inhibit our ability to sleep

that night can actually enhance the

function of the immune system and this

is something that I don't think is

talked about enough you know we hear so

often that quote unquote cortisol is bad

it's a stress hormone listen cortisol is

fantastic provided that it is elevated

early in the day and not late in the day

or evening also cortisol does have

thresholds Beyond which if it's too high

can be bad for us but it's also the case

that if cortisol levels are too low

that's bad for us and it's especially

bad for the functioning of our immune

system because glucocorticoids of which

cortisol is have an important role in

activating those natural killer cells of

the innate immune system they are one of

the primary signals by which those inter

lucans like interlan 1 and interlan 6

are deployed in our body and so very

often we'll hear stress increases

inflammation and indeed interlukin 1

interlan 6 are pro-inflammatory you

might think oh my goodness I don't want

that I don't want cortisol I don't want

these Incans elevated but guess what the

inflammation response is also an

important component of that innate

immune system that allows us to combat

infections so in trying to keep our

innate immune system tuned up I realize

that's not a biological statement tuned

up but keep our immune system

functioning at its best we want

inflammation available as a tool to

combat infection we want cortisol

available as a way to activate that

inflammation and other aspects of our

immune system we just don't want so much

cortisol and so much inflammation that

we can't sleep and that our gut

microbiome suffers and that brings me to

the other component that's important for

the basic functioning of your immune

system so that you can be at your

strongest when you inevitably encounter

those cold and flu viruses why do I say

inevitably look if you exist in the

world that is if you live live on planet

Earth you are going to be bombarded with

different viruses and bacteria and

funguses and all this stuff throughout

your days and yes in those winter months

because people are spending more time

indoors and they're touching each other

and surfaces more breathing on each

other more sneezing on each other more

and so on and so forth there is more

propagation of colds and flu so if we

take a step back and we ask how can I

have my immune system as strong and

ready as possible to combat cold and flu

viruses we get to those Basics it's make

sure you're getting enough quality sleep

each night how much is enough however

much you need in order to not feel

sleepy during the day except maybe the

requirement for a short nap of anywhere

from 10 to 30 minutes not everyone

requires that but that's perfectly

normal to have an afternoon dip in

energy that can be restored with a short

nap or non-sleep deep bre we'll provide

links to non-sleep deep breast and other

tools in the show note captions that you

know are zero cost tools to allow you to

recover your energy some people just

simply take a nap and that sort of thing

if you want tools for improving your

sleep and making sure that you're

getting enough quality sleep each night

we will also provide a link to our zeroc

cost sleep tool kit that details that in

PDF form it just lists out the things

that you can do or take if that's your

choice and so on and so forth and of

course we've done episodes on quality

nutrition and what that means we've done

episodes on stress and how to combat

stress and we've done episodes on the

so-called gut microbiome but right now I

just want to mention that the gut

microbiome which are the trillions of

little microbacteria that interact

heavily with the immune system and help

support the immune system you want to

keep the gut microbiome healthy so

you'll notice that we include some tools

related to the gut microbiome here in a

moment and and this is very important

keep in mind that the microbiome doesn't

just exist in the gut so often these

days we hear about the gut microbiome

and I'm oh so happy that the gut

microbiome is getting the attention that

it deserves in the context of mental

health physical health and performance

but we can't forget that the microbiome

also exists on the surface of the eye

and in the nasal passages and indeed the

microbiome that's specific to the nasal

passages as I mentioned before is very

different from the microbiome that

exists within the mouth and the

microbiome that exists within the mucosa

of the nasal passages seems to be the

most effective at combating any viruses

that we encounter especially cold and

flu viruses so while ideally you would

never encounter a colder flu virus we

know that if the colder flu viruses go

in through the nasal passages you stand

the greatest chance of combating that

particular cold or flu so what does that

mean this is where I get to make a

strong push for being a nasal breather

certainly in sleep you want to be a

nasal breather but also throughout the

day unless you're speaking or unless

you're exercising hard enough that you

need to breathe through your mouth or

unless you're eating being a nasal

breather is known to provide the right

millu the right environment to keep that

nasal microbiome at its healthiest and

to promote the diversity of microbiota

in the nasal passages that can best

protect you against colds and flu and

there are a growing number of studies

that point to this fact I'll provide a

link to one that I like very much which

is entitled alterations in oral nasal

Fingal microbiota and salivary proteins

in mouth breathing children this is but

one study pointing to the fact that

being a nasal breather is a good thing

mouth breathing children and mouth

breathing adults meaning children and

adults that default to mouth breathing

tend to get more in C of of the upper

respiratory tract including colds and

flu consciously focusing on nasal

breathing is one of the best things that

we can all do to combat any colds or flu

that we might encounter so earlier we

talked about trying to avoid touching

your eyes at least without washing your

hands first or sanitizing your hands

first after you meet somebody keeping in

mind that most people do that

unconsciously here we are also saying

when you enter a room you're hanging out

with peoplebe you're waiting for public

transportation or you're at work work or

walking down the hallway unless you are

exercising hard unless you are talking

try to focus on being a nasal breather

there are a bunch of other reasons to be

a nasal breather as well but this is one

of the primary ones and I'll 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 open themselves up to increased

levels of viral infections as well as

bacterial infections but viral

infections in particular when they rely

on mouth breathing and the incredible

benefits of doing this very simple zeroc

cost thing of whenever you can

consciously remember to breathing

through your nose as opposed to

breathing through your mouth and just as

an additional point about nasal

breathing because I can't resist telling

you this I just think it's so cool such

an interesting

adaptation when we breathe through our

nose we heat the air in a way that's

very different from the way we heat the

air when we mouth breathe and by heating

the air that's coming into the nasal

passages it shifts the probability that

colder flu viruses will successfully

embed in the mucosal lining and infect

the underlying cells and get into the

other cells and tissues of our body so

this whole thing about nasal breathing

is important and effective at the level

of temperature regulation of the millu

within the nose and therefore the

viruses that end up in the nose as well

as the mucosal line and the chemicals

made by the mucosal line

and again the nose is a very different

place than the mouth in fact I'll

provide a link to yet another paper uh

which is entitled human nasal microbiota

it's a really interesting paper it's

actually an interview with a scientist

who's expert in the nasal microbiome

talking about how this structure within

our nose really is the primary defense

site by which we destroy potentially

incoming viruses so if it sounds overly

simple just breathe through your nose it

is very simple but it's also very

effective now it's also clearly the case

that keeping your gut microbiome is

advantageous for keeping your innate

immune system at its most robust level

of functioning and I should mention that

your gut microbiome isn't just about

your stomach you know we hear the word

gut and we think stomach but it's

actually the entire length of your

digestive tract from your mouth out the

other end and different microbiota exist

at different locations along that tract

of mucosa and there are a couple things

that one can do in order to make sure

that the gut microbiome is best

supported along that entire length the

first one is that and this was covered

on the episode that we did with my

colleague Justin sonenberg who is a

world expert in the gut microbiome and

that is to consume anywhere from two to

four servings of low sugar fermented

foods per day so things like sourkraut

things like kimchi things like kefir

things like kombucha it can be a little

bit of work to figure out which of these

you like and which ones you're willing

to consume on a regular basis but it's

very clear that the brine you know that

kind of uh salty solution around the

sauerkraut and by the way when I say

sauerkraut what we're talking about here

is the type that has to be refrigerated

it contains what are called live

cultures as opposed to the sauerkraut

that can exist in the non-refrigerated

portion of the store or pickles that

also have that Brine and that have to be

kept in the refrigerator even before

they're opened and of course like yogurt

which have active live cultures those

are the sorts of things that are going

to best support the diversity of

microbiota along the entire length of

the gut microbiome such that your gut

microbiome can do its job in supporting

your nervous system but here especially

in the context of today's discussion

your immune system now the low sugar

component of low sugar fermented foods

is important because what we know is

that if you're consuming yogurts with a

lot of sugar or you're consuming

kombucha with high levels of sugar or

you're consuming pickles or sauerkraut

that have a lot of sugar in them you're

probably going to start to create some

other issues related to the sugar what

you're really looking for are these low

sugar fermented foods and they can be a

little bit tricky to seek out in the

store but they're usually there and once

you identify the ones that you like you

should really aim to get two to four

servings of those per day you can also

consume a Prebiotic or probiotic in the

form of capsule form things like ag1

athletic greens also contain Prebiotic

probiotic but it's very clear that

consuming two to four servings of low

sugar fermented foods per day is among

the best ways to promote health of the

gut microbiome and that the gut

microbiome is so so important for

keeping the innate immune system

thriving such that it can combat the

colds or flu that are trying to bombard

your system now there's another tool

that you can use to enhance your gut

microbiome I have to warn you this one

might make a few of you um cringe a

little bit but this is one that I

actually started doing about four months

ago um it's an interesting one it kind

of dates back to some older quote

unquote traditional medicine practices

but it makes really good logical sense

to be fair I'm not aware of any

randomized control trial exploring the

use of this protocol but it's so simple

and completely cost-free and it stands

so strongly on the logic of how the gut

and oral microbiome work that frankly I

started doing it and you know whether or

not it's placebo effect or not I don't

know but I feel better and it's so easy

to do and it stands to potentially

improve the fun of your gut microbiome

enough that I figured I would at least

share it with you and then you can

decide so what this protocol essentially

consists of is before you go to sleep at

night or in the morning you pour

yourself a little bit of water whatever

water you happen to consume just clean

clear water 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 that are like oh gross

let's think about this is it really

gross to swish a little bit of water

around in your mouth and then swallow

that water when you first wake up prior

to brushing your teeth of course well it

might seem gross to you but throughout

the night when you're sleeping

especially if you are a nasal breather

while you sleep the environment within

your mouth is such that you're breeding

a lot of bacteria you are creating all

those little

microbacteria that potentially can

inhabit your digestive tract and provide

at least some of the substrate for the

microbiota in your digestive tract to

thrive and if that seems gross to you

keep in mind that's what having a

healthy gut microbiome really is all

about so the protocol is very simple at

zero cost you take a swig of water swish

it around and swallow it oddly it

doesn't taste bad um in fact it'll just

taste like swallowing um and in fact it

tastes like swallowing a little bit of

water it's not as if it tastes like um

bad breath or something like that it's a

very simple protocol that again no

randomized control trials but really

stands 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 such that it

supports the function of your inate

immune system such that you can avoid

colds and flu at least to me it seems

like a pretty low bar yes okay so to

bolster your inade immune system you

want to get that quality sleep as often

as you possibly can you want to support

the gut microbiome in the ways that we

just described what about exercise we

hear it all the time time exercise is so

good for us it enhances the immune

system and on and on and listen I'm a

huge believer in exercise I personally

like to do three bouts of cardiovascular

exercise per week one long one medium

one short and I do three bouts of

resistance training each week all of

that and specifically what I do is

available to you as a zeroc cross

protocol in the form of a PDF we have a

link to that in the show note captions I

also have a whole episode about

foundational Fitness and so on and so on

the discussion we're going to have now

now is about what general forms of

exercise actually do support the innate

immune system and and this is really

important what forms of exercise

actually deplete your innate immune

system this isn't talked about enough I

think there are certain intensities and

durations of exercise that make us more

vulnerable to colds and flu so we're

going to discuss that before we do that

I want to just briefly touch into

something that I hear a lot which is the

question if I'm feeling a little bit

rundown should I exercise or not and to

be honest there isn't a straightforward

answer to that question it's impossible

for me or for you to know whether or not

you were indeed exposed to a cold or flu

and you're starting to combat it at the

level of your Nate immune system or

whether or not you're just you know

feeling a little bit

sluggish however what we do know is that

if you are feeling malaise at the level

of the body like your body is feeling

different it's feeling heavier you're

feeling tired you're feeling 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 how much sleep

you got the night before right I mean

here what we're talking about is ruling

out any possible you know life stressor

you were up too late or you drank

caffeine at the wrong time or something

like that what we know is that you're if

you're feeling that General malaise

across your whole body it is fairly

likely that you're coming down with

something and that your best response to

that would be to go home take a hot

shower or bath I'll explain why you

would want to do that in a few minutes

and then get into bed early and even if

you can't fall asleep to just be as

still and as relaxed as possible we know

that if you push into bouts of intense

activity or even just push yourself to

engage in activity when you're feeling

run down at that sort of whole body

level maybe a little tickle in your

throat you are going to compromise the

function of your innate immune system

and it's very likely that you're going

to get more sick than you would

otherwise so here's my suggestion if

you're starting to feel rundown at the

level of whole body malaise or you just

don't feel right

you're best off taking a hot shower bath

and getting into bed or just getting

into bed and trying to rest and get as

much sleep probably even a little bit of

extra sleep and here's why that whole

body malaise that extra fatigue that's

not easily explained by other factors in

your

life have to do with the fact that when

your innate immune system is activated

meaning it's already combating a cold or

flu interlukin 1 and interlukin 6 have a

way of interacting with a particular

brain area called the dorsal rafay

nucleus which is choa block full of

neurons that release serotonin and

serotonin from the dorsal rafay nucleus

acts on specific regions of your

hypothalamus areas like the preoptic

region for those of you that want to

know and other areas of the hypothalamus

that generate a state of sleepiness in

addition when we are getting sick our

sleep patterns change 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 circuitry involved in sleep

that controls slow wave or deep sleep

and this is a whole discussion unto

itself I actually covered a lot of the

mechanistic aspects of this business of

immune induced sleepiness and Malay is

associated with feeling sick in an

episode about interactions between the

neural and immune system that I will

also provide a link to in the show note

captions but suffice to say if you're

feeling that whole body Mala is and

especially if you also have a little bit

of a throat tickle you're just not

feeling right for you you're not

accustomed to feeling that way at that

time of day or night well then I

encourage you to get rest because

chances are you're already combating an

infection however if you are out and

about a lot during the winter months or

you're interacting with a lot of people

by virtue of work or public

transportation or whatever the gym Etc

you're a school teacher maybe your kids

are coming home with colds and flu and

you're not yet feeling that malaise

you're not feeling any throat tickle

you're not getting that kind of um kind

of burning or tickle within your nasal

passages when you breathe you know we're

all familiar with these things the

watering the eyes that kind of precedes

the getting the full-blown cold or flu

well if you're not experiencing that

stuff and you want to keep your inate

immune system strong and able to combat

off colds and flu then we know that

exercise can be an excellent way to

increase the output of that innate

immune system what I mean by that is the

appropriate intensity and duration of

exercise can act as a stressor that

promotes a bit of inflammation yes the

release of cyto kindes and a bit of

activation of the innate immune system

including the production of more white

blood cells natural killer cells such

that you're sort of prompting the innate

immune system to almost think that

there's something to battle such that if

you ever encounter an infection you can

defeat it right off the bat so we're

going to get granular here about what we

mean by proper intensity and duration of

exercise there's a wonderful review that

was published in 2019 in the Journal of

Sport and Health Science entitled The

compelling link between physical

activity and the body's defense system

and there's a lot to this review article

but I'll just highlight a few of the

critical features that are going to

directly relate to protocols that I

think all of you are going to be

interested in first of all we know that

exercise that's of 60 Minutes in

duration or less and that is intense but

not allout effort okay here we're not

talking about percentage of single

repetition max weight here we're not

talking about 70 to 85% of one's VO2 max

what we're talking about is you

subjectively gauging what is a 10 out of

10 effort like you could not do any more

you could not contribute any more effort

to that exercise bout and that's true

whether or not we're talking about

resistance training exercise or

cardiovascular exercise like running or

rowing or things of that sort what we

know is that if you do that sort 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 innate immune system such

that not just during exercise but for

many many hours afterwards maybe even as

much as 24 hours afterwards your innate

immune system level of Baseline activity

is ramped up allowing you to better

combat infections such as colds and flu

okay so this is an incentive for getting

a regular exercise of 60 Minutes or Less

per

day making it of sufficient intensity

for your anate immune system to deploy

more of those chemicals and for your

lymphatic and blood circulation to

increase their exchange of materials

enough that your Nate immune system is

bolstered however it is absolutely not

the case that more is better in fact

it's probably the case that less is

better here's what we know for sure and

this review covers sort of the extreme

of these examples but for instance

people that do bouts of walking each day

for about 60 Minutes brisk walking

experience

increased te- cell function so that's an

immune cell that goes out and combats

cold and flu viruses and natural killer

cell activity so those increase increase

macras function you are now familiar

with these cells if you don't know

exactly what they do just keep in mind

that you heard about these in the

context of what the innate immune system

does to go out and fight colds and

flu cyto coses increase but not

dramatically okay so this is a mild

inflammation response stress hormones

such as cortisol epinephrine norep

nephrine also called adrenaline and

noradrenaline those are deployed as well

so 60 minutes or less of this moderate

to high-intensity exercise creates this

mild stress response and an increase in

the function of the inate immune system

however people that run a marathon and

as I recall a marathon is 26.2 miles if

I'm not

mistaken they experience a very

different pattern of immune response to

that long bout of exercise so here we're

comparing one hour of exercise to 3

hours is that what it takes to run a

marathon I have some friends that are

marathoners I'm guessing about three

maybe four hours if you're really slow

but somewhere between you know I don't

know two and a half and three hours if

you're trained up and you're doing it

and you're doing them regularly well

here's the point people who just ran a

marathon and people who have been

training for a marathon and are

approaching that Marathon are severely

immune compromised the levels of their

te- cell function are way below Baseline

meaning their inate immune system is not

functioning nearly as well as it would

if they were to not exercise at all

their natural killer cell activity is

also greatly diminished these are huge

huge reductions in these cells that is

in the function of the inate immune

system and their stress hormones and

their inflammatory molecules such as

cyto circulating in their blood are

extremely high now again we're

representing opposite ends of the

spectrum here with 1 hour or less of

exercise daily versus 26.2 mile marathon

exercise or half marathons 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 that's great just understand

what you're doing to your immune system

when you do that and take the necessary

precautions but I think most people

listening to this are trying to think

about ways that they can avoid getting

colds and flu and certainly running

marathons is not going to be the way to

do that quite the contrary the way to do

that is in addition to the other things

we've been talking about to get regular

exercise maybe not every single day I'm

actually aan of taking one day per week

completely off from exercise usually on

that day I'll do some sauna and cold if

I have it available to me but the point

is this you don't have to exercise for

an hour a day in order to get this

Improvement in the inate immune response

data show that you can get this

Improvement in anate immune response

with as little as 20 minutes per day and

probably even as little as 12 minutes

per day however if you're going to try

and accomplish this increase in the

innate immune system function or output

with a shorter bout of exercise such as

12 minutes it better be 12 minutes of

very high-intensity training in fact

that's what lands on my uh for me it's

Friday but it doesn't really matter

which day of the week there is one day

of the week where I do a very short bout

of cardiovascular exercise but I'm

sprinting hard for anywhere from 20

seconds to a minute and then I'm taking

a brief period of rest and then

repeating that for a total of 12 minutes

now some people here oh only 12 minutes

of exercise required and they default to

12 minutes every single time they train

I don't think that's a good idea I think

we can take the law of averages here and

say the following I do believe everyone

should do a combination of

cardiovascular training and resistance

training perhaps I think in general not

on the same days but if you're going to

do that and you want to maintain healthy

immune system function my suggestion

what I do is unless it's the long bout

of cardiovascular training that I do

once a week and long for me means 60 to

90 minutes and sometimes longer if it's

a hike which certainly doesn't require

that much intensity

I 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's

required to complete what you need to do

in order to keep with your exercise

goals but to be very careful about

exceeding 75 minutes of exercise in any

one single exercise bout and if you

remember back to the beginning of the

episode when I said that I track what I

do on a day-to-day basis and I don't do

it in a very detailed way but I do take

note of when I've gotten a bad flu or

cold I can tell you that in almost every

single case where I've gotten a bad flu

or cold there are two things that have

preceded that bad flu or cold one is

sleep deprivation typically it would be

nights where I got two hours of sleep or

less for more than one night okay the

second thing is anytime that I really

pushed it with exercise and went all out

and I went for 75 minutes and then I

continued to 90 minutes and then maybe

later that day because somebody invited

me on a run or something like that I

also did that second run or that second

workout of some kind could be running in

the morning and weight training in the

afternoon some people can do that kind

of training on a regular basis even and

not get sick I am not such a person I've

managed to maintain fairly consistent

Fitness output meaning the three

cardiovascular and the three weight

training sessions per week for more than

several decades now and part of the

reason I think I've been able to do that

is because I don't ever push too hard

for too long within a given workout so

this is really a call for moderation in

terms of the duration and intensity of

the exercise that you're doing but we're

not talking about really being laidback

we're not talking about easy workouts

what we're talking about is an hour or

less of moderate intensity to

high-intensity exercise depending on the

duration of that exercise and keeping in

mind that when you're doing that you are

activating that innate immune system you

are literally creating an immune

response you're increasing inflammation

you're increasing those cyto kindes

you're increasing stress stress hormones

we have to start to think about exercise

for what it is which is a form of stress

that induces adaptations Dr Andy Galpin

talked a lot about this in the series

that he did on exercise physiology it's

an excellent series that covers

everything from strength to hypertrophy

to speed to endurance nutrition

supplementation you can find all that at

hubman lab.com very

easily exercise is a very potent tool we

know that we know that in the context of

changing Aesthetics like body mass

composition you know increasing muscle

reducing fat we know that in the context

of reducing resting heart rate reducing

resting blood pressure we know that in

the context of all these other health

metrics here we're talking about using

exercise as a very potent tool to

increase the function of the Nate immune

system to keep you healthy not just

through the winter months but around the

year and especially if you're getting

less sleep if you're interacting with

kids or adults that are carrying

infections home from school or work on a

regular basis or maybe you even work in

an environment like a hospital or a

clinic where you're regularly

interacting with patients that have

these issues one thing that I often get

asked is if I am sleep deprived should I

exercise and that's a little bit of a

tricky one my initial response for many

years was no no if you're sleep deprived

you're better off not

exercising however I now need to qualify

that answer because there are data

showing that if you're sleep deprived

and you exercise especially if you

exercise early in the day and it doesn't

disrupt your sleep schedule so it's not

making you go to sleep even later the

next night that it actually can cause

some adjustments in the function of your

immune system and in the way that you

regulate your blood sugar that offset

some of the negative effects of sleep

deprivation that said you should never

ever compromise the amount of sleep you

could get in order to get exercise such

that you run yourself down so what I'm

really saying here is if you get one bad

night's sleep should you skip your

workout and you feel like ah you know

I'm not feeling sick and should I work

out or should I go back to sleep

probably going back to sleep is the

better idea but if you don't have the

option to go back to sleep for whatever

reason you can't fall back asleep then

you would be wise to do a bout of

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 sleep

deprivation for that one night keep in

mind exercise is not a replacement for

sleep and then to allow you to get to

sleep at the appropriate time later that

night and back onto a regular schedule

keeping your innate immune system tuned

up and ready to combat any colds or flu

now one more point about exercise and

here we're also going to dovetail in an

important point about nutrition in the

review that 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 the

production of white blood cells and so

on it's very clear that if you are in a

state of chronic stress because you're

you're exercising a lot Andor because

you're not sleeping enough or for

whatever reason maybe you have a lot of

Life stress it's very clear that

ingesting

carbohydrates after exercise can help

attenuate some of the inflammation that

exercise

induces when we talk about carbohydrates

we're talking about rice oatmeal pasta

those sorts of things soal complex

carbohydrates and fruit post exercise

has been shown to attenuate to reduce

some of the markers of inflammation by

about 30 to

40% when contrasted with water only

intake especially if you're training

fasted so for those of you like me that

like to wake up in the morning and just

drink fluids you know for me it's water

y bate coffee and by the way I've said

before that people should delay their

caffeine intake 90 minutes if and only

if they're experiencing an afternoon

crash but that if you are exercising

first thing in the morning it's

perfectly fine to ingest your caffeine

right away so that gives you increase in

energy for that exercise that's

certainly what I do on days that I

exercise but if you fast and then you're

drinking caffeine and then you're

exercising and that exercise goes longer

than 60 Minutes certainly if it goes

longer than 75 minutes you would do well

to ingest some complex carbohydrates

maybe also some fruit perhaps not

immediately after exercise but within

the 45 minutes or so or hour or so after

exercise so that you're not ramping up

those inflammatory molecules and leaving

them ramped up for many hours into the

morning and throughout the day because

of course this episode is not about

exercise and nutrition but here we're

talking about the role that exercise and

nutrition play in helping us combat

colds and flu by increasing the function

of that innate immune system and the

reasons why carbohydrates can have this

effect on cortisol Etc is an interesting

and important discussion into itself

we'll leave it for another episode but

keep that in mind also I don't know