How the Gut Microbiome affects the Brain and Mind

How the Gut Microbiome affects the Brain and Mind

Thanks to Squarespace for sponsoring this
video. One summer afternoon when Doctor Martin Blaser
was still a medical student, he went to see an eleven-year-old boy who had suddenly become
ill and was hospitalized. He was perfectly fine until two days earlier when he suddenly
developed a fever and an upset stomach. The next day the fever worsened, and on the third
day, the boy developed small purplish dots on his body. The emergency room doctors quickly
realized the boy had Rocky Mountain spotted fever, something caused by a bite from a tick
infected with a type of bacteria called rickettsia. This bacterium multiplies within cells lining
blood vessels, invoking an aggressive immune response. Since this involves the brain’s
blood vessels, it caused a form of encephalitis, a swelling of the brain provoking a massive
headache. When Blaser accompanied doctors to see the
boy, the room was darkened as the light hurt his eyes, his body was covered with purple
spots, and he was thrashing around in his bed covered in sweat. He was yelling incoherently
as loud as he could while hallucinating. As Dr. Blaser explains in his book “Missing
Microbes,” the boy was started on an antibiotic called tetracycline and after just five days,
he was discharged from the hospital. Especially considering the Gut Microbiome
is the big topic in health and science recently, you may know that not all microbes are bad.
While there are pathogenic microbes like these just mentioned, at all times there are 500
to 1000 different species of bacteria in the human body. And the importance of their function
is becoming more apparent as we learn new things about them. However, it’s hard to picture how tiny microbes
in our gut contribute to our day to day cognition and brain function. In the case of rocky mountain
spotted fever it may not be surprising that the introduction of a deadly pathogen could
induce drastic changes in a person’s mental state. However, the relationship between the
microbes normally residing in the gut and how our brain operates becomes apparent when
we take them out. Scientists observing microbe-free mice living
in sterile bubbles quickly noticed that these mice have a personality that is distinct from
mice with gut microbes. Microbe-free mice were found to be more prone to taking risks
and they freely explore their environment. Risk taking might be good if you’re a young
entrepreneur, but the kind of risk these mice engage in is wandering further out in an open
field. For a mouse, this is an excellent strategy for quickly getting killed by a predator.
Not only are the mice unusually reckless, scientists also noticed that these microbe-free
mice have memory-related defects. The book “The Good Gut” by Erica and Justin
Sonnenburg describes how a group of researchers put normal and microbe free mice through some
memory tests. First, the mice were given five minutes to explore two new objects, a small
smooth ring and a large checkered ring. Then the objects were removed for twenty minutes.
After that, the large checkered ring and a new object, a star-shaped cookie cutter, were
put in the cages. Predictably, the mice with the normal microbiota checked out the cookie
cutter and paid less attention to the checkered ring because they already knew what it was.
The microbiota free mice, explored the new cookie cutter, but spent just as much time
checking out the old object – the checkered ring. It seemed that these mice had completely
forgotten an object they had just seen twenty minutes earlier. The forgetfulness in these mice may be explained
by the fact that the microbe free mice have lower levels of BDNF. BDNF, brain-derived
neurotrophic factor is a powerful protein important for learning and memory. It stimulates
the production of new brain cells and strengthens existing ones. Low levels of BDNF are linked
to depression and anxiety. Since making microbe-free humans would be
quite unethical, such experiments haven’t been repeated in humans, but… you may have
heard of the woman who, after receiving a fecal microbiota transplant, became obese.
The fecal microbiota transplant or FMT is just as it sounds, it’s taking the poop
from one healthy person and putting it into another person, in order to share the healthy
microbiota of the donor. FMT is not a common practice, but it’s the most effective treatment
for a Clostridium difficile infection, which causes diarrhea and abdominal pain for weeks.
In this case, the woman’s donor was her 16 year old overweight but otherwise healthy
daughter. The transplant went smoothly and successfully cured the woman’s issues. But,
over a period 16 months, the woman gained 34 pounds. And this happened despite persistent
diet and exercise efforts. She even went on a medically supervised liquid protein diet
and still could not get the weight off. On the flipside of this, it’s been found
that putting the microbiota of lean mice into other mice protects them from gaining weight.
So it looks like a microbiota transplant can transplant body types, but what about personality? In 2011, a research group at McMaster University
did an experiment with two different types of lab mice. One type had a personality that
was the mouse equivalent of anxious and the other type was sociable and extroverted. To
set a metric for how nervous the mice were, they put them on an elevated platform and
recorded how long it took for them to step down. The mice with the anxious personality spent
an average of four and a half minutes slowly and carefully making their way off the platform.
The “extroverted” mice jumped down in seconds. Then, the scientists switched the
microbiota of the two types of mice and did the platform test again. The mice with the
extroverted personality, after receiving the microbes of the anxious mice, now took over
a minute to get off the platform. On the other hand, after getting the microbes from the
extroverted mice, the “anxious” mice got off of the platform a whole minute quicker.
What this group showed was that in these mice, behavior and levels of anxiety were dependent
on which microbes were living in their gut. One other thing: remember BDNF, the protein
that we should like to have more of for better brain function? Well, the microbiota switch
that made the “anxious” mice more “confident” also increased their levels of BDNF. The change
in microbiota not only made observable changes in behavior, but in brain chemistry as well. In fact, there’s all kinds of chemistry
going on in the gut that can affect the brain. There’s even research identifying which
specific microbes produce which neurotransmitters. For example it’s estimated that 90% of our
serotonin is produced in the gut, and it’s been found that some of this serotonin is
produced by these four microbes. These two microbes produce gamma-Aminobutyric
acid or “GABA” – our chief inhibitory neurotransmitter which has relaxing and anti-anxiety
effects. And these two (Bacillus and Serratia) produce
our motivation neurotransmitter, dopamine. [R] So we basically have this huge mass of little
drug factories sitting in our gut pumping out different substances that affect our brain.
In fact the gut and its microbes appears to affect the brain so much that preclinical
research in rodents suggested that certain probiotics have antidepressant and anti-anxiety
effects. Probiotics are basically substances you can take orally to stimulate the growth
of microbes. One study even found that a Bifidobacterium infantis probiotic had anti-depressive effects
on par with that of the anti-depressant drug citalopram. I used to think that the only benefit of fiber
was that it helped you poop. However, considering dietary fiber isn’t food for us but for
our microbes, a diet rich in fiber from a variety of sources should also be good for
our mental health. This information about the gut microbiome
makes you start to wonder how many mental afflictions could be traced back to disruptions
in gut health from, for example, diets rich in fiberless processed foods and refined carbohydrates,
or from the unmitigated use of antibiotics. Antibiotics can be a life saver when absolutely
necessary as we saw at the start of the video, but the most commonly prescribed antibiotic
– a wide-spectrum antibiotic doesn’t just kill the offending bacteria, but all kinds
of other bacteria get caught in the crossfire. This is like poisoning your cat along with
a bunch of cockroaches you’re trying to kill. In the United States alone, tens of millions
of people are prescribed antibiotics for minor afflictions. 60 to 80 percent of children
taken to the doctor complaining of bad sore throats or ear pain will walk out with an
antibiotic. It’s estimated that people will take 30 courses of antibiotics by the age
of 40. But, the highest prescription rate was for children under the age of two with
1,365 courses per 1000 babies. So, could all these antibiotics affect the
young gut microbiome and the brain development of these children? A 2012 paper by Dr. Derrick MacFabe describes
what happens when rats are injected with something called Propionic Acid or PPA. The PPA injection
provoked peculiar changes in the rats’ brains like neuroinflammation, increased oxidative
stress, and glutathione depletion.The rats also displayed abnormal movements, repetitive
interests, cognitive deficits, and impaired social interactions. Basically, the results
of this injection were very similar to autism spectrum disorders. And, PPA is a fermentation
product of bacteria, namely Desulfovibrio, Bacteroidetes and Clostridia. It was found
that patients with autism have many more species of the clostridium bacteria and have high
levels of PPA in their feces. It’s estimated that in one third of patients,
autism doesn’t show up until around 18 to 24 months. Several reports from parents say
that their children were developing normally until they received antibiotics for upper
respiratory or ear infections. According to Dr. Sydney Finegold, antibiotics wipe out
or suppress several organisms in the gut, but Clostridia is one of the ones that persists. A CBC program titled “The Autism Enigma”
features Ellen Bolte who explains how her son Andrew’s behavior changed drastically
after 6 courses of antibiotics over a 2 to 3 ½ month period for an ear infection. After
this, he was diagnosed with severe autism. Digging into the research, Ellen came across
information about the Clostridia bacteria, so she started searching for a doctor who
would be willing to try an antibiotic called “vancomycin” on Andrew. Vancomycin is
specifically designed to target the Clostridia bacteria. After she finally found a doctor
who agreed to test her theory, they tried the antibiotic and it had impressive effects.
“The results were astounding. Within a matter of just a few weeks, he became calm. He was
aware of his environment… he’s putting puzzles together…” The antibiotic brought out improvements
in Andrew that were transient but drastic. This case lead to a pilot study with Dr. Finegold
and a Dr. R Sandler who found that out of 10 autistic children treated with vancomycin,
8 of them had again transient but significant improvements. Now, jumping to conclusions about the cause
autism has not been… helpful in the past… but this idea that autism could be the result
of a disturbed gut is gathering more and more data. A disturbed gut ecosystem would also
explain the very common gastrointestinal issues autistic children suffer. Some estimates say
that as high as 70% of children with autism spectrum disorders also have gastrointestinal
issues. Autism is just one of the disorders that can
be linked to a disruption in gut health, and research on the gut microbiome is growing
quickly. About 3600 related articles on this topic were published between 2010 and 2015.
At this point, saying the gut microbiome is important to health is an understatement.
Dr. Martin Blaser says that “losing your entire microbiome outright would be nearly
as bad as losing your kidneys or liver.” Unlike the kidneys or liver however, you can
change the makeup of your microbiome with what you put into your mouth. I guess Hippocrates knew what he was talking
about when he said “All disease begins in the gut,” and “Let food be thy medicine.” This video was brought to you by Squarespace.
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  • Elizabeth Marks-Graham

    I finally got this to play

    Now I wonder if Autism is in the gut not the brain

  • Elizabeth Marks-Graham

    Ooooooo I wonder if putting the bacteria in someone with a food allergy into someone without a food allergy would they develop the same allergy ?

  • Mike Grover

    First that is NOT a mouse you are showing in the video but a rat!!!! How can we believe the rest if the "scientists" can't even get that very basic difference sorted out. It's like a sales man telling me that a motorcycle and a car are the same thing and are covered by insurance the exact same way.

  • Sweetie

    IBS and depression almost completely reversed on a meat and greens diet. Food is medicine!

  • reformedfruit

    I love how the video clips don't quite match up with the narrative, such as the diseased kid suddenly elevating in the room.

  • MrThefrederic

    I thought I was going crazy when I noticed my mental state improve after taking probiotics, it's a very interesting topic.

  • the POW/MIA newspot

    VANCOMYCIN did help with C. Diff BUT it was No CURE for me. Took Two times then a Third time with more than TWICE the first two batches and over a gtime frame of three times the first doses.. STILL I had to take something Else that Maybe has CURED IT…BUT the Medical community NEVER DID OFFER ME anything that Killed C. Diff.. THATS GREAT it worked for him–it was better than the first Metro????? dose..they gave me..
    THANKS MUCH for your info..

  • The Fish Bowl

    TMI but is it possible to "accumulate" the microbes present in my partner's semen if I swallowed it? I know it sounds like a joke, but I'm usually on the more extroverted side and while me and my partner are overtly sexually active, I've began to notice that I have picked up traits of my partner that I've never had before, like stomach grumbling and anxiety. I am shook any answers or am I just overthinking this?

  • EsenJolie

    i luv dis voice

  • The Savage Wombat

    After many years of trying, Doctors were finally able to kill a couple test subjects using FMT involving an infected donor. FMT studies have been put on hold indefinitely. Big Pharma is breathing a heavy sigh of relief.

  • Rodney Moorman

    brain it on theme ftw

  • kris kemp

    Dr. Berg said that fasting increases levels of BDNF and, also, restores youth, energy, cures depression and has many, many other beneficial effects. Fasting and Urine Therapy and No Fap cures just about anything.

  • kris kemp

    autism is also caused by vaccines

  • Get Informed

    Very informative…. thanks!

  • aldret aldret

    Is there a law which forbids laboratories to make scientific experiences on babies, children, with medicine ? It seems that I am not sure after seeing the video but I may have not understood, certainly. So…I need to see the video again… Or, let us see in the comments, first.

  • B Meetze

    Vaccinations change the gut biome too which contributes to ASD. I have a “gut feeling” (pun intended) that they failed to mention that in this piece. Children commonly get ear infections and other infections from vaccinations because they change how the body’s natural immune system works. This leads to gut issues and the information presented in this video. Don’t vaccinate and you’ll see a tremendous decrease in the occurrences of an imbalanced gut biome.

  • Richard Benoit

    Thanks for the post

  • arcassia art

    yo where can i get 5 bags of Einstien's poop

  • Wak Job

    Waiting on that magic pill that fixes all our guts.

    It's coming.

  • 365Days

    I am pretty sure that for most people their brains is just a backup copy of their asses.

  • Dimitar Dobrev

    4:40 ish omg

  • peter phoenix

    this is magic mushroom fungi works so well…

  • J Newsom

    Joe Rogan would approve this…

  • Andres

    Here Lab guy, as your doctor for a reason why he thinks you have strep throat and as a test, culture tests can be done in 3 days and give you the specific antibiotic but YOU AS PATIENT NEEDS to learn to WAIT and COME EALRY TO the hospital.
    You teach your kid that if throat feels funny to tell you.
    Learn from Nurse to check for inflammation and inflammation in the lymph nodes under the jaw and neck.
    See signs, take it to the doctor and get a culture test. Get the result and target the bacteria.
    Now Viruses can be killed on with Roche Tamiflu, antibiotics are useless for viruses like the common cold, flu or influenza.
    People need to ask first.

  • SofaKingAwesome23

    Yo does any smart rich person have any spare poop

  • K. Ganesan Ganesan

    Tell it to all schools Government offices Bus stand Railway Station in India.

  • Robby Chajkow

    First…. there are 2 Brains , the small one in your head and the much larger one in your heart ,do your research

  • Robby Chajkow

    This is accurate on the smaller brain connection to the gut

  • Lao Mark

    I have been claming about the importance for the overall health of the types of bacteria/ microorganism in the guts since 1987 but nobody gave a damn, as usual.

  • HoneyedHylian

    If I eat like asians, will I finally be as smart as one?

  • jkjkjk

    How did YouTube know to suggest this? I was just taking about it with my family this morning

  • Lunazul

    Do you mention Wakefield in your video?

  • Thomas Mortensen

    Sounds hard to believe. Are those sources peer-reviewed? Those experiments are definitely of the kind that needs to be reproduced to see how they hold up.

  • Timberwolf Powler

    If you cannot eat spicy hot food you already need help. As well the dumbing down of America began with RX drugs, fast food, GMO garbage and pesticides.

  • we see the ligh

    Utube : Gary Ward urine therapy
    Utube : dry fasting
    Utube: Andrew Webber , distilled water

  • Jim Lee

    If this is true, it blows my mind. But then it does make sense when thinking about diet.

  • Greg Bly

    This is where my Concentration of personal health is . Gut bacteria helps to produce all of the chemistry needed to function properly. Antibiotics kills most bacteria . This is probably the cause of much mental dysfunction. Also do people realize that oxidizer,s are also produced in out gut as part of our immune system. Anti oxidents and antibiotics are very much misunderstood.

  • Chris Vaccaro

    9:10 – love their hats

  • wms72

    Poop transplant pseudoscience. The mom who gained weight after getting her fat daughter's poo could have emotional or other issues. Correlation is not causation.

  • aku suka nasi

    I guess that extroverted mice got GUTS.

  • Dakota Jones

    What I learned from this video:
    Eating poop makes you fat. :/

  • Habeebullah A

    One of the best video i saw recently

  • SpiritualOpportunism

    Nature vs nurture vs parasite vs microbe?

  • SpiritualOpportunism

    WHAT?! Well what food should I eat them?

  • Mel Pascal

    Sooooooo who wants to switch poop?? 💩

  • hyrich

    imagine watching this whole thing and at the end they tell you they made it all up

  • alun williams


  • Girish S

    I was a perfectly normal kid till 14, that's what my parents tell me. But I've been showing ADHD symptoms since then. I can't remember if I was prescribed any antibiotics at that exact time, but I know that my doctor usually prescribed Amoxycillin (a broad spectrum antibiotic). He still does. Going to take this very seriously and see if it works. Wish me good luck.

  • Randy Fricke

    Stop eating wheat IMMEDIATELY!!!

  • haarp35117

    What did that have to do with the kid at the beginning that took the

  • mahmud rabbii

    Shout out to all the rats died for better human civilisation

  • Peregrine Moss

    Well done!

  • Autumn

    These poor mice! 🐁🐀

  • essennagerry

    10:46 – ha, vancomicin is my only allergy. 😀 But doctors said many people have an allergic reaction to it.

  • Four Horsemen

    I was prescribed antibiotics for the simple flu my entire life. I took what the doctors gave me as back then we didn't have easy access to research. Now I have the most resistant strain of candida that no medication responds to. I'm focusing on diet, oil pulling etc but the doctors literally destroyed my life for nothing.

  • Alfred rice

    Probiotics pill are destroyed in the stomach due to acid content prebiotic may be more helpful .give the body the minerals and nutrition it needs it will produce more probiotics . The test results are there check out how to increase your gut biome

  • Kamila I.

    Elon Musk should start to sell poop that he is producing!

  • bb b


  • gamescomgamer

    So, is it better to eat a large variety of fermented food, and see which bakteria survive, or eat a specific food more often to help that specific type to grow?

  • Anuja Churi

    Thank you tons for this ! Thank you so much !!!

  • I love Animals I love Animals

    Remember also,that most of our meat and eggs are full of Antibiotics

  • Erich Pizer

    great vid.

  • Łukasz S.kyWalker

    Big Thx!!

  • fenrirgg

    So remember to feed your bacteria buddies with those crunchy vegetables.

  • Abhijit Desai

    Gut microbioms may also be driving some instincts within animals. I have seen dogs eating specific type of grass when they have an upset stomach. Dogs otherwise would never do that.

  • helicart

    LOL. WIL has recenly uploaded vids re the benefits of lots of animal produce.
    Based on his autism spectrum disorder, in about 20 years he'll wake up to how animal produce compromise optimal gut microbiome.

  • xy Z

    Is there any slim ready-made bug for selling…

  • operamaniak81

    Not all gut bacteria eat fiber – actually most of them don't. Those eat fat, sugar or protein and more. Diet rich in fiber and carbs, while poor in fats and protein, induces change in the gut bacteria landscape – the populations of the species having too little of their food shrink or extinct, and with them their products – while fibreous ones dominate. Many body and mind disieses could be linked to disbalanced gut bacteria scene – one of the hypothesis says that particularly the sugar-eating bacteria make a person eat more sugar and get fatter as a side effect.

  • WTF Happened To Me

    Very useful video thank you

  • B watson

    I was prescribed penecillin 5 years ago, i took it for 2 days. Made me so fuckin sick..ive never felt the same again.

  • Wisdom Searcher

    People and modern medicine deeply underestimate how an healthy gut bioma is central for overall wellness

  • Sigma Geranimo

    Drink more Alcohol , it kill the bacteria.

  • Prenom Nom

    1:11 Is it some sort of sick way of saying the child died?

  • Gina C

    Antibiotics routinely fed to the billions of factory-farmed animals has an impact on human gut health also and not just the antibiotics prescribed from doctors. Eating animal flesh and cow milk messes up gut health (and mental health), too

  • Carol Burnett

    you just said…..what about transferring personalities………just a note….All folks might not have read this but……..when we come into Jesus family and we are saved, we get a portion of the mind of Christ (the loving Savior). and also it says elsewhere that we come into a new covenant and that we now have a new person living inside of us………………….wow – now these scriptures make even more sense… (seems like we have a new DNA too)

  • Sir Footinmouth

    He didn't say anything about the thousands of parents saying the symptoms immediately arose after am adverse reaction to a vaccine


  • jon hamm

    i wonder if this microbiome swapping could eradicate depression in humans ?

  • MrKnifeart

    I might have lyme, definitely something in my gut triggering Migraines monthly. What is the solution??

  • Debra Erb

    This was amazing!

  • Crash 1974

    “Affects” the brain, cmon guys.

  • N BOR

    How responsible are antibiotics for the growing autism epidemic (now less than 1 in 100 in USA)

  • Sathish Yadav

    Thank u

  • amy ortiz

    poop transplant, thats disgusting.

  • Guava Pastries

    Hmm I wonder if this correlates with why this generation seems to have way more mental health issues (especially anxiety and depression) than previous ones.

  • Snippets

    Kids, always listen to your gut, because you are what you eat 🙂

  • Rabia Banu

    You guys fucked up mice mentally by switching poops.

  • Scott Powel

    More rats shown than mice, but all were referred to as mice. Not trying to be a troll, this is very interesting and well presented. Thanks for sharing with us.

  • tins offish

    Everyone in a he comments seems to ignore they just figured out why there are fat people..

  • ayahuascamaharaja

    So, according to this video… everything anti-vaxxers are anxious about was, in reality, antibiotics?

  • Parnian Naghipour

    6:40 come to ma babies

  • Vance Biondo


  • Vance Biondo

    ☝️ I FEEL AWSOME!!!!!

  • Libertie Aguiba

    I'm currently learning about this in my pathogenic bacteriology class!! Such a cool topic!!

  • Dr . A . Rosenberg

    Eat more red meat and drink more whole milk and you will be fine !

  • Faith Factory

    The amount of knowledge in this video could potentially save life and families it is so incredible thanks so much

  • Aganju

    The Archons and what they do

  • Connor Duke

    My son received broad spectrum antibiotics in the first week of his life and indeed later developed autistic symptoms. We are now using bifido probiotics and resistant starch (from potatoe starch) to help turn him around. Vancomycin we are considering as well.

  • Cosmonauta Pleyadiano

    Check out for Dr Natasha Campbell Mcbride book "gut and psychology syndrome"

  • Alex T

    When I heard that the gut microbiome could be linked to autism I got pretty irritated and angry. But now hearing the evidence behind it I'm quite interested..

  • celestialdream49

    Was the House actors reimbursed for this video??

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