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Health Begins in the Gut: Why Gut Microbes Produce Health or Disease with David M. Ferriss, MD, MPH

Health Begins in the Gut: Why Gut Microbes Produce Health or Disease

Are you ready to take charge of your health? Schedule your free 20-minute discovery call with our New Patient Coordinator to see how you can become a patient at MaxWell Clinic and start your healing journey today.


It’s no secret that what we eat has a huge impact on our body, but did you know that the bacteria in your gut also play an important role? The trillions of microbes living in your digestive tract are crucial to your health and well-being. When the microbes in your gut get out of balance or there are too many bad bugs it can lead not only to gastrointestinal problems but impact heart health, brain health, and immune health.

Wondering how to improve your gut health?

Watch the video as Dr. Ferriss shares what steps will ensure you have plenty of good microbes in your gut. Making choices that keep your gut healthy will help you live a long, happy and exciting life!


Understanding the Gut-Brain Connection: Your Guide to a Healthy Microbiome

The human body is a complex ecosystem inhabited not only by its cells but also by trillions of microorganisms. This intricate network of microorganisms, collectively known as the microbiome, plays a pivotal role in maintaining our overall health. In recent years, scientific research has shed light on the profound impact of the microbiome on various aspects of our well-being, particularly in the realm of mental health. In this blog, we will explore the gut-brain connection and delve into how a healthy microbiome can positively influence both our physical and mental health.

The Gut-Brain Axis: A Two-Way Street

Imagine your body as a bustling metropolis, with communication highways connecting every part of this vast city. In this analogy, the gut-brain axis is the central freeway that allows constant communication between your gut and brain. This bidirectional communication system relies on various mechanisms, including neuronal connections, hormones, and the immune system.

Research has shown that the gut microbiome is intricately linked to mental health. Conditions such as depression and anxiety have been linked to alterations in the composition of the gut microbiota. While this connection is complex and not fully understood, it is clear that the gut microbiome plays a role in modulating our mood and emotions.

The Rise of Nutritional Psychiatry

Nutritional psychiatry is a burgeoning field that explores the relationship between diet, gut health, and mental well-being. It emphasizes the pivotal role of our diet in shaping the composition of our gut microbiome and, subsequently, its impact on mental health. A diet rich in whole foods, plant-based sources, and fiber is considered one of the cornerstones of a healthy microbiome.

Fiber, in particular, serves as a vital food source for the beneficial bacteria in our gut. These microbes, often referred to as probiotics, thrive on fiber, which helps them flourish and maintain a balanced ecosystem. When we consume a diet lacking in fiber and abundant in processed foods, we starve these friendly microbes, potentially disrupting the harmony of our gut microbiota.

Probiotics: Guardians of Gut Health

Probiotics are live microbial organisms that can provide numerous health benefits when consumed in adequate amounts. While probiotics can be found in fermented foods like yogurt, kefir, and sauerkraut, they are also available in supplement form. Research has identified specific probiotic strains that may aid in weight management, reinforcing Dr. Haasey’s insights on the role of probiotics in this context.

Over 500 studies have linked probiotics to behavior, particularly in cases of anxiety and depression. While probiotics offer a promising avenue for enhancing mental well-being, they are not a magic cure. Instead, they are one piece of the puzzle when it comes to achieving and maintaining good mental health.

Prebiotics: Fueling Your Microbial Allies

Prebiotics are therapeutic supplements that serve as food for the beneficial bacteria in your gut. By mimicking the nourishing properties of a healthy diet rich in fiber, prebiotics encourage the growth of these microbial allies. Incorporating prebiotic-rich foods into your diet, such as garlic, onions, and asparagus, can further support a flourishing gut microbiome.

It’s crucial to recognize that while probiotics and prebiotics have their merits, they should complement, not replace, a wholesome diet and lifestyle. A balanced diet that nourishes your gut microbiome remains the foundation for optimal health.

The Promise of Fecal Transplants

In severe cases of gastrointestinal distress, such as recurrent C. difficile infections, fecal transplants have emerged as a groundbreaking treatment option. C. difficile is a troublesome microbe notorious for causing severe diarrhea and other debilitating symptoms. Traditional antibiotic treatments may not be effective for all individuals, leading to chronic suffering.

Fecal transplants involve transferring fecal material from a healthy donor with a balanced gut microbiome to the colon of the afflicted individual. The results can be astonishing, often leading to rapid symptom improvement and, in many cases, complete resolution of the infection.

This innovative therapy underscores the profound impact of a healthy gut microbiome and the potential for therapeutic manipulation to restore health.

Conclusion: Nurturing Your Microbial Garden

In summary, the gut-brain connection is a fascinating area of scientific exploration that highlights the crucial role of the microbiome in shaping both our physical and mental health. The state of our gut microbiota is influenced by various factors, including diet, lifestyle, and exposure to antibiotics. While probiotics, prebiotics, and even fecal transplants offer exciting therapeutic possibilities, they should complement a healthy lifestyle.

Maintaining a diverse and balanced gut microbiome requires a commitment to a diet rich in whole foods and fiber, regular physical activity, and mindful antibiotic use. The future of healthcare may involve personalized approaches to optimize the gut microbiome, ushering in an era where microbial health is as important as any other aspect of well-being.

As you embark on your journey to better health, remember that the trillions of microbial inhabitants within you are not mere passengers; they are active participants in the intricate dance of your body’s ecosystem. By nurturing your gut microbiome, you empower it to work in harmony with your body, contributing to a healthier and happier you.

So, as you navigate the path to better health, embrace the wisdom of nurturing your internal microbial garden. Your gut may hold the key to unlocking a happier and healthier life.


Are you ready to take charge of your health? Schedule your free 20-minute discovery call with our New Patient Coordinator to see how you can become a patient at MaxWell Clinic and start your healing journey today.

good afternoon i’m dr david ferris with
the maxwell clinic and i want to welcome you to our latest
group visit which is the latest in a series of topics that we’re covering
to communicate information that we as clinicians think is important for our
patients to understand today we’re going to be talking about how health begins in the gut and just
how important it is for us to have good gut health and why
it matters not only for physical health but for our mental health as well
before we get started a couple of housekeeping items
you will be on mute but if you have a question please type your question into
the q a box and i’ll attempt to answer as many of those questions
as uh time permits after the the remarks that i make and in
the unlikely event that the internet goes down uh we will switch to a hot spot so just
uh hang on for a few minutes and uh we’ll hopefully be able to continue the webinar in the unlikely
event that we have an internet connection problem
all right let’s jump in uh i want to start with a couple of definitions
uh you’ll hear the terms human microbiota and human microbiome
when we talk about human microbiota we’re referring to all the different
microbes probably well over a thousand different microbes that reside on and in
each of our bodies when we talk about the human microbiome we’re talking about all of the
microbial genes that reside in and on the human body so human microbiota
refers to all the microbes themselves when we talk about the human microbiome
we’re talking about all of the genes in that collective group of of microbes
that reside in or on our body so
each of us as human beings has approximately 10 trillion cells that
comprise our bodies but each of us has approximately 100
trillion microbial cells in and out of our body so in a very real sense uh
our human cells are are way outnumbered by our microbial cells
furthermore each of us as humans has approximately twenty thousand genes
but we carry some two to twenty million microbial genes
in and on our bodies this means each of us has far more microbial genes than human genes in our
bodies another way of looking at this is to say that 92
of the total genes in our bodies come from microbes which is a little daunting when uh when we
think about it and these microbes and their genes play a more important role than we can
imagine the research in this area of the
human microbiome and particularly the gut microbiome which we’re going to
focus on today uh has been exploding over the last couple of decades and continues to to
explode research has linked microbes to a number
of conditions and these are only some and the list continues to grow but obesity
arthritis autism anxiety and depression
are all conditions which there has been established a
significant microbial link in terms of the effect that the composition of the
microbes particularly in our guts have on these conditions
so what i’d like to do next to kind of set the stage for the rest of the presentation
is to show you a a short video uh this is a video that i came across
several years ago i’ve used it in a number of presentations and i think it tells in a an engaging and humorous way
communicates a lot uh about the importance of our gut microbiome
and um and and its significance for us so let’s hope the technology works and
we’ll play this and then uh and then i’ll continue
the next time you look in the mirror think about this in many ways you’re more microbe than human there are 10
times more cells from microorganisms bacteria viruses fungi than human cells
in and on our bodies and our genes are outnumbered 100 to 1 by microbial genes
scientists even have a name for all these microbial genes the human microbiome
now this might make a lot of people rush for the hand sanitizer but it turns out most of these
microorganisms aren’t bad germs that will make us sick most are good and
without these good microbes our bodies don’t seem to do as well we don’t seem to be as healthy and we
actually might get sick more often so one question is where do our
microbiomes come from in the first place well like a lot of things it starts with our mothers
as the infant passes through the birth canal it gets coated with microbes from the mom
these microbes may kind of seed the baby with just the right mix combined with bacteria and breast milk
and other microbes we encounter early on they seem to slowly take shape in our first few years of life
the overall mix of our microbes becomes very personal sort of like a fingerprint or maybe a blood type but our microbes
tend to resemble those of our parents and siblings and may stay with us for much of our lives
[Music] they may also be doing all sorts of things such as educating our immune
cells like this one teaching them the difference between things they should fight off bad bugs
that might make us sick and things that aren’t a threat like our good microbes [Music]
when we’re adults microbes become our first line of defense fighting off germs that try to invade our bodies protecting
their turf while protecting our health [Music] scientists have discovered they can even
spew out their own antibiotics
the types of microbes in your body vary depending on exactly where they live like different ecosystems in nature
there are wet places like our mouths noses and armpits oily places like our
scalps and backs and dry places like our forearms different species of microbes have
adapted to each of these habitats the biggest most important microbial
habitat seems to be in the gut it’s the most complex the most diverse and
everything microbes are doing everywhere else in our bodies fighting off infections revving up and dampening down
our immune systems signaling cells that’s all happening in the gut in spades
they even seem to help regulate our metabolisms how much energy we burn
so if it’s not functioning for some reason because of what we eat antibiotics we take that may actually
lead to all kinds of diseases diseases like colon cancer colitis maybe even
diabetes and obesity some scientists think one reason a lot
of diseases are increasing is because we’ve lost key gut microbes our microbiomes look far less diverse
compared to those of people in less developed countries and earlier generations and remember how we get our microbiomes
in the first place from our mothers when we’re born and from breast milk well some scientists think that too many
babies aren’t getting that because of all the c-sections and not enough breastfeeding plus all the antibiotics
kids get these days and our obsession with cleanliness all this may help explain why problems
like asthma and allergies have been soaring maybe because our microbiomes never taught our immune systems how to
work the right way
maybe swallowing good microbes probiotics could prevent and treat some diseases
so could taking prebiotics essentially food that good microbes love
[Music] we end our story with a reminder this
research is really new we still have a lot to learn about what many of our microbes are really doing but scientists
say that it’s getting clearer and clearer that the tiny organisms all over our bodies are essential to our health
and happiness
[Music]
oops there we go sorry so uh i hope that was helpful in in just
giving a a nice overview of the importance of uh our microbial friends to uh to
health and as the video said um we first get our microbes from from our
mothers uh an unborn child to the best that we understand now although there’s some debate about this
uh basically start as sterile they don’t have any microbes
on them or in them but as the baby passes down through the
birth canal of the mother then the baby picks up the microbial
flora in the mother’s vaginal tract and that inoculates the baby
uh their guts and their skin their mucous membranes
for what is the beginning of a very important uh immune defense
uh and a regulator of of so many things um with
respect to to health as the video pointed out as well
babies born by means of c-section which has been a significant percentage
of of children in past decades they have different microbes because
they’re not passing through the vaginal um tract of the of the mother
um and so they’re going to pick up their first microbes from typically
their their mother from nurses caring from them from others through skin contact
uh and they’re going to be seated with very different microbes than others and and we think this may be
one of the reasons that c-section is associated with increased rates of
asthma immune system issues food allergies and atopic disease in children that were
born from c-section in fact um dr rob knight whom i’ll
mention again in in a minute is one of the leading
uh scientists in the world he’s at uc university of california san diego
in this area of the gut microbiome he tells the story of when several years
ago he and his wife had their first child a daughter
they had to have an unexpected c-section at the last minute and knowing what he did about the
importance of inoculating uh newborns with the right
microbes from the mother’s birth canal he actually took secretions from
his wife and they inoculated their daughter with those in order to try to
mimic what would have happened had their daughter had a normal non-c-section birth
so i’m not aware that that’s being done very widely um or certainly routinely at
this point but it’s possible that uh it may be in the in the future
so as that infant grows and develops and they start eating
more solid food and probably between six and nine months of age
then diet begins to influence the composition
of their their gut microbiomes we know that breastfeeding versus
formula feeding produces different results
i think it’s well established that breastfeeding is the optimal food for
for newborns and and babies uh whenever that’s that’s possible
um but uh breast milk has certain microbes
uh that uh we’re still learning what role they play
in the development of the baby’s immune system and in the baby’s
overall health um it’s it’s probably fair to say that
in the long term um we are what we eat because our diets
do make a huge difference in what our microbiomes
of our guts look like we know from studies in different uh
human populations around the world that have very different diets
that they have different uh microbes inhabiting their guts
for example for populations who have a lot of meat in
their diet which would be true of most developed countries including
the u.s these individuals tend to have much
higher number of bacteroides species in their guts
whereas individuals that live in parts of the world
where the diet has very little meat and is predominantly complex carbohydrate
grains they have a predominance of species
called prevotella so we’re seeing these differences uh still learning about what’s the
significance of those differences in in the gut microbiome of different
peoples with different diets and uh you know what is the prevalence
of different diseases different conditions in these different populations and more and more we’re
discovering that there’s a strong tie to um to the the gut microbiome
so let’s talk about sickness and health for a minute um as i’ve already referenced our microbes
have already been linked to a wide spectrum of disease this has been demonstrated
both in animal studies and in human studies and
you you see these some of these repeated and some additions
from a previous slide inflammatory bowel disease multiple sclerosis autism
depression anxiety obesity allergy these are some of the lists which i
think will become far longer that we know that the gut microbiome and its
composition uh has a connection in some way to these diseases we’re still trying
to elaborate the details of that i mentioned dr rob knight at uc san
diego a couple of minutes ago he
is director of the microbiome initiative at the university of california san diego a major
world research lab in this area and he’s also co-founder of the american gut
project and the earth micro biome project these were major projects which
he uh helped start to analyze the
uh the gut microbes of uh thousands if not by now millions of
people around the world and particularly in the us to understand uh the connections between
uh what’s in our gut micro microbiomes and
and the health or the disease that we experience and i thought this was a bit humorous
but it’s based on his research and the research of others his advice for
healthy children is first have a dog but start early
ideally in the prenatal time
live on a farm with cows and straw that’s probably not going to apply to most people but at least
be outside and what you’ve heard about um you know perhaps it’s okay for for kids
to play in the dirt a bit and we shouldn’t uh freak out if we see them
then touching putting their fingers in their mouths which particularly small children will
inevitably do it’s not the end of the world and it may play a very important role in helping
train uh these children’s immune systems to to function in in an optimal way
avoid antibiotics early in life especially antibiotics can be
life-saving and so we’re very thankful for them but they have been grossly
overused for for many years and so good advice is not to use an
antibiotic unless it’s really necessary and then to use it for a shorter period
of time as will eradicate the offending micro but this is particularly true
early in life when the the child’s microbiome is so malleable
children and adults will recover uh from a course of antibiotics but but
it takes some time it may take weeks to months for them to restore a more normal
microbial composition after a course of antibiotics
and then breastfeed as i’ve already alluded to breast milk has certain microbes which
we’re still learning about the the impact of them on health particularly in
infants but this is important so in short
exposure to a diverse array of microbes is important and we’re seeing that in
the adult research as well having a diverse
number of different species particularly species that we’ve identified as being
particularly beneficial to health is is really important
let me take just a moment to talk about the gut brain axis
undoubtedly if you’ve been a patient at maxwell clinic for very long you’ve probably heard your provider talk about
the connection between the gut and the brain and this is an area where research has
exploded in recent years as we’re learning more and more about how the gut
communicates with the brain and how the brain communicates with the gut
uh there’s increasing evidence that our gut microbiome influences
who we become and how we feel microbes not only influence how we
digest our food how we absorb drugs and produce hormones but they also interact
with our immune systems to affect our brains and it’s these interactions between our
gut microbes and our brains that’s what we call the gut brain axis
or the gut brain connection and thus far we’ve elicited a number of
different mechanisms for this communication between gut and brain we know there are neuronal
um connections hormonal and immune mediated mechanisms
that that that enable this communication between gut and brain so it’s a
fascinating area of research and one that continues to expand
um as i’ve said earlier but we know the microbiome has been linked to depression
and anxiety and we’re still trying to tease that out and how we might uh use
uh changes uh in the gut microbiome through
therapeutic means to help reduce anxiety and depression in
individuals it’s it’s not the single thing but it’s one of a number of important factors
that that contribute to good mental health in fact there is a whole
uh field of psychiatry that is developing and getting inclu increasing
attention called nutritional psychiatry in which
scientists are studying how diet as we’ve already said
has a huge impact on the composition of our gut microbiome and then subsequently
how the gut microbiome through the uh brain uh gut axis
is impacted in terms of our mental health um
probably all of you are familiar with the term probiotic these are actual living microbial organisms
that we frequently administer to patients when
the gut when their gut health is less than optimal they may be experiencing
leaky gut which is quite common and we use these microbes
in the form of probiotics for perhaps a period of months or perhaps
even longer term to help bring about beneficial changes in the health of that individual
to date there are more than 500 studies linking probiotics to behavior
especially for anxiety and depression so again just an area that continues to
to grow in its importance so finally
i want to talk for just a minute about how can we change our microbes to
improve ourselves to specifically to improve our health
we know that we modify our microbiome all the time um by what we eat
if we change the the balance of carbohydrates that we’re eating uh and
the amount of protein that we’re consuming particularly animal protein
uh it changes the microbiome um probably the the healthiest diet and
this is not news to most of you uh would be a whole food plant-based
diet one that is rich in phytonutrients has abundant uh fiber in it
um and uh it’s the fiber that our beneficial
bacteria in our guts uh really thrive on so if we want to feed the good bugs then
eat a healthy diet lots of vegetables lots of fruits legumes whole grains
minimize the uh the animal protein of the eggs the
the dairy they have can have a place in the diet but most individuals particularly in
the u.s and other industrialized countries
do not eat nearly enough complex carbohydrates you know all the colors of
the rainbow in the diet lots of fiber the other thing that impacts our
microbiome is alcohol so to the extent that we utilize alcohol
it may benefit or have deleterious effects on our microbiome and our health and
then of course we’ve already um i’ve already spoken about the issue of antibiotics
and how while antibiotics can be life-saving we want to use them only when really
necessary to achieve the desired end and improve health because of the toll that they can take
on our gut microbiomes 40 alluded to probiotics which are
live organisms usually delivered in a capsule form
to help replenish healthy microbes in the gut
when when improvement is is needed an individual there’s also the category
of of therapeutic supplements called prebiotics and these are really substitutes that
that mimic the healthy diet that i just spoke of these are high in
in fiber and they feed the healthy the healthy microbes that we want whose
growth we want to encourage in the gut so we use a lot more probiotics and we
do prebiotics both have a place but again neither one of these
these supplements can substitute for a healthy diet that’s foundational along with exercise for a
healthy life let me wrap up my remarks
with an example of uh something that is already uh being more widely and widely
used and that’s in patients who have developed a chronic c difficile
infection uh c difficile is a really noxious
microbe it tends to produce severe diarrhea in individuals most
people when they’re diagnosed they’re treated with an antibiotic and that’s appropriate
uh quite a number will improve with that and be cured but there’s a certain
significant subset of those individuals who are treated with antibiotics that have recurrent c difficile and
their lives become quite miserable with with the chronic diarrhea and bloating and abdominal pain
that they experience so um an application of this whole area
of gut microbiome science has been fecal transplants
taking fecal material from healthy volunteers who have healthy guts and
transplanting that into the colons of individuals who are
experiencing a c difficile infection with all of these
severe symptoms of diarrhea and other gastrointestinal distress
and so in the vast majority of these individuals who receive a fecal
transplant um the results can be pretty amazing
uh within many times just one to two days there is a significant improvement
in uh in the symptoms of these individuals with c-difficile
difficile infections and and a large percentage of these individuals
get a complete cure so their their their treatment and their cure was giving them healthy microbes
from a healthy volunteer uh transplanting those into
the guts into the colons of the of the afflicted individuals so that’s
just one example i think we will probably see many more
examples of this as we learn more about our microbiome
how do we get it healthy how do we keep it healthy and when we’re sick how can we
therapeutically manipulate our gut microbiomes to restore them to health
and and improve the the overall health and well-being of of these individuals
so um that concludes the remarks that um i had
planned to um to make i hope this has given you at least
something of a high level overview i anticipate that
in the future we will dive more deeply into some of the subtopics related to
this in other group visits uh certainly the we we could talk for some time about the
gut brain axis that i mentioned briefly and its importance to overall health and
particularly to uh to mental health so with that i’m going to stop the uh
my screen share for the presentation and we’ll go to
q a and see what questions
um yes first question is uh one
whether refers to dr haasey’s presentation last week about various
supplements and he said that there was a probiotic that it’s been found that may help with
with weight i deluded to earlier that we know the microbiome is related to um
obesity and so there there are probiotics with particular
strains that have been found to to aid
achieving a more normal a healthier um [Music]
body composition so i would completely agree with what
what dr dr hazy said i think as we learn more about the
microbiome there probably be even more advances and uh we may be um
um we may be able to um to do to do more in this area
again it won’t be it won’t be the magic bullet it will be one probably of a number of things the
most important thing we can do to achieve and maintain a healthy weight
is through our diet and that diet can directly support a healthy gut microbiome
and so just swallowing whether their supplements or pharmaceuticals
will not generally get us well and keep us well certainly to optimize our health
um we have to go back to those lifestyle fundamentals but that can be helpful
uh was asked the name of the supplement and um you know i’m it’s escaping me at
the uh at the minute it is one of the um the probiotics that we we uh we carry
um so i’m sorry i i don’t want to misspeak so i’ll have to i’ll have to recheck that to make uh
make sure i have that correctly but we’ll be happy to to tell you
i don’t know whether there are other questions if there are i’ll wait just a minute and
pause to submit those are the only two that have come in thus far
but if you have another question please submit that now and
i’ll be happy to try to respond to that
all right if there is aren’t any uh further questions
then uh thank you for your attendance thank you for your participation in these group visits
um as we discussed doing these several months ago with the launch of maxwell
care our intent is to be able to talk in more detail about a wide variety of topics
that we think are important for achieving maxwell health but that um even a 45
minute or hour long patient visit doesn’t allow us the time to do that so i hope this is helpful
thank you for your attention and i hope you’ll uh keep coming back for uh
other group visits uh webinars in this series thanks so much

This blog provides general information and discussions about health and related subjects. The information and other content provided in this blog, website or in any linked materials are not intended and should not be considered, or used as a substitute for, medical advice, diagnosis or treatment. This blog does not constitute the practice of any medical, nursing or other professional health care advice, diagnosis or treatment. We cannot diagnose conditions, provide second opinions or make specific treatment recommendations through this blog or website.

If you or any other person has a medical concern, you should consult with your health care provider or seek other professional medical treatment immediately. Never disregard professional medical advice or delay in seeking it because of something that you have read on this blog, website or in any linked materials. If you are experiencing a medical emergency, please call 911 or call for emergency medical help on the nearest telephone immediately.

David M. Ferriss, Jr., MD, MPH

David Ferriss, MD is a board-certified preventive medicine physician with a special interest in the role of a healthy lifestyle in the prevention and reversal of chronic disease.