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Acid Reflux causes and Treatment

Flashback Friday: Prebiotics: Tending Our Inner Garden

Flashback Friday: Prebiotics: Tending Our Inner Garden


“Prebiotics: Tending Our Inner Garden” The total surface area of our gut
is maybe 3,000 square feet, counting all the little folds,
larger than a tennis court, yet only a single layer of cells separates
our inner core from the outer chaos. The primary fuel that keeps
this critical cell layer alive is a short-chain fatty
acid called butyrate, which our good bacteria
make from the fiber we eat. We feed the good bacteria in our
gut, and they feed us right back. They take the prebiotics we
eat, like fiber, and in return provide the vital fuel source that
feeds the cells that line our colon, a prototypical example of the kind of
symbiosis between us and our gut flora. How important are these compounds
our good bacteria derive from fiber? There is a condition
known as diversion colitis that frequently develops in
segments of the colon or rectum after surgical diversion
of the fecal stream, meaning if you skip a segment of
the bowel, like with an ileostomy, so that food no longer passes
through that section, it becomes inflamed and can start
bleeding, breaking down, closing off. How frequently does this happen? Up to 100% of the time — but the
inflammation uniformly disappears after you reattach
it to the fecal flow. We didn’t know what caused it — maybe some kind of bacterial
over-growth or bad bacteria? Or was it a nutritional deficiency
of the lining of the colon due to the absence of the fiber needed
to create the short-chain fatty acids? We didn’t know until this study
where they cured the inflammation by bathing the lining in what
it so desperately needed. Severe inflammation gone
in just a few weeks. We feed the good bacteria in our
gut, and they feed us right back. It makes sense that we have good
bacteria in our gut that feed us, tries to keep us healthy. They
got a pretty good thing going. It’s warm and moist and food just keeps
magically coming down the pipe, but if we die, they
lose out on all that. If we die, they die, so it’s in their
best evolutionary interest to keep our colon happy. But there are bad bugs too,
like cholera, that cause diarrhea. They have a different strategy. The sicker they can make us,
the more explosive the diarrhea, the better their chances of spreading
to other people, into other colons. They don’t care if we die because they don’t intend on
going down with the ship. So how does the body keep
the good bacteria around while getting rid of the bad? Think about it. We have literally trillions
of bacteria in our gut and so our immune system
must constantly maintain a balance between tolerance to good bacteria
while attacking bad bacteria. If we mess up this fine balance and
start attacking harmless bacteria, it could lead to inflammatory
bowel disease, where we’re in constant
red alert attack mode. The mechanisms by which
the immune system maintains this critical balance remained
largely undefined until now. If you think about it,
there’s got to be a way for our good bacteria to signal
to our immune system that they’re the good guys.
And that signal is butyrate. Butyrate suppresses
the inflammatory reaction, tells our immune system
to stand down. So butyrate may behave
as a microbial signal to inform our immune system
that the relative levels of good bacteria are
within the desired range. Butyrate calms the
immune system down, saying, in effect, all’s well; you
got the good guys on board, ultimately rendering the intestinal
immune system hyporesponsive, meaning accommodating
to the beneficial bacteria. But in the absence of the
calming effect of butyrate, our immune system
is back in full force, attacking the bacteria within our
gut because they’re obviously not the right ones since
butyrate levels are so low. So we evolved to have butyrate
suppress our immune reaction, so should our good bacteria
ever get wiped out and bad bacteria take over, our immune
system would be able to sense this and go on a rampage and
destroy the invaders, and continue rampaging until
there were only good bacteria creating butyrate to put the
immune system back to sleep. OK, here’s the critical piece.
Here’s why this all matters. What if we don’t
eat enough fiber? Remember, our good bacteria
use fiber to create butyrate. So if we don’t eat enough fiber, then
we can’t make enough butyrate. We could have lots of good bacteria,
but if we don’t feed them fiber they can’t make butyrate. Sensing such low levels of butyrate,
our body mistakenly thinks our gut must be filled with bad bacteria
and reacts accordingly. Our body can mistake
low fiber intake for having a population
of bad bacteria in our gut. Our body doesn’t know
about processed food. It evolved over millions of years
getting massive fiber intake. Even during the Paleolithic period,
100 grams of fiber a day. So, on fiber-deficient Western diets,
eating our Spam on Wonderbread, when our body detects low
butyrate levels in the gut it doesn’t think low fiber —
as far as our body’s concerned there’s no such thing as low fiber —
it thinks bad bacteria. Because for millions of years,
low butyrate means bad bacteria, so that’s the signal for our body
to go on the inflammatory offensive. So that’s one reason why fiber
can be so anti-inflammatory, one of the reasons fiber intake
is critical for optimal health. Not fiber supplements,
but whole plant foods. Fiber supplementation with
something like Metamucil may not replicate the results seen
with a diet naturally high in fiber.

42 Replies to “Flashback Friday: Prebiotics: Tending Our Inner Garden”

  • The 7-video keto series continues next week. Be sure to subscribe here or at nutritionfacts.org/subscribe so you don't miss any! -NF Team

  • Thank you for your insight. I should increase my veggies even more, as my turmeric and spice saturated cruciferous veggies and leafy greens done in coconut oil really do feel like they palpably reduce inflammation in the colon. Is supplementing with a BHB supplement, as I have tried recently before exercise, also have the same effect? I know it gives me energy.

  • How do we know that the Paleolithic diet had 104 gms of fiber and 1956 mg of calcium per day on a plant based diet? I call BS. that’s some researcher’s n=1 guess.

  • This is a super great one, but from around 4 minutes in to 5, the screen does not change, and a HUGE important thing is explained, that deserves its own series. Nevermind the Keto nonsense, do a whole series on butyrates and the HARM of low fiber diets!! We all know how stupid Keto is. The only explanation for it is that the meat only diets have turned its adherents into meatheads.

  • Dr. Greger, I overstand all of the conveyed concepts in the video, but have a question. If the diet is low in fiber, and the wholesome bacteria feed on the fiber that makes it to our gut, and unwholesome bacteria can crowd out the wholesome just as the opposite can happen, then if one is consuming a low fiber diet, it would be essentially the same as starving the wholesome bacteria, correct? And if so, would that not create an environment where the unwholesome bacteria could thrive where previously unable? So, in that case, the body wouldn't be imagining troublesome bacteria from a low fiber diet, they would actually be there from the lack of fed healthy bacteria. Does that make sense? 💓☮️🙏 thank you so much for all your assistance and service to the world <3 let's translate these into every language!

  • Does this therefore mean that healing IBS, SIBO and other digestive issues requires a short term low fiber diet to signal to the body that all is not well and it needs to attack the disbiosis of bad bacteria in the digestive system???? Since the presence of fiber in one's diet is telling the body all is okay when there is disbiosis one would want to encourage the body's response that all isn't okay. So cutting off fiber does this???

  • Once upon a time, millions of years ago, in a land far, far away … I can't believe anyone believes in creation! After all, I'm a smart scientifically-grounded professional who believes in the Big Bang, where the whole universe just popped into existence out of nothing. MUCH more scientific.

  • I ingest about 2 tbsp of crushed flax seeds every day, along with all my other good plant-based foods. I've been told that it's too much but I've been doing it for quite a long time and have seen no ill effects. What's the deal?

  • I’ve been interested in the gut microbiome for over a year now. 4 years ago I had a total colectomy after many years of ulcerative colitis and then colon cancer so I have a permanent ileostomy. In the spring of last year I underwent a second repair to a parastomal hernia and this surgery was followed by a serious post-operative infection. I was on 3 different cocktails of IV antibiotics before they got on top of it, and discharged from hospital with the oral version. A friend introduced me to fermented probiotic foods and I have been making and consuming these ever since (kefir, kombucha, sourdough). It was through this that I first became interested in the gut microbiome and did a lot of my own research into this utterly fascinating subject.

    There is always a lot of emphasis on the health of the colon and its billions of microbes, but I cannot find anything about people in my situation. I know that research into the gut microbiome is a relatively new area, and I am part of a minority group but I would love to see some work done on this. When the colon is removed, do the healthy colon bacteria end up in the small intestine? I am in the process of transitioning to a whole-foods plant-based diet because of the tremendous health benefits and also weight loss but I have no colon to benefit from all the extra fibre! I have noticed that my stoma output has increased quite a lot since adopting the new diet, and it can’t be doing me any harm – I am fortunate in being able to eat pretty much anything I like as long as I chew it well – but nobody seems to be able to answer my questions. My own health professionals (colorectal surgeon, stoma nurses) don’t have any training in nutrition, let alone a whole-foods plant-based diet, and the only dietary advice I got was to keep to a low residue (low fibre) diet for the first 6 weeks after my surgery, and then begin to “eat normally.” I really do want to find out more about all this in relation to my own situation.

  • Honey is a good prebiotic, and butter/dairy literally contains butyrate. Remember milk is the food for a babie who can't digest anything.

  • Dr. Greger can you please address the information that Dr. Steven Gundry discusses in his book the plant paradox. He claims that legumes and some other plant foods can actually be detrimental to health and promote disease because of a protein called lectin. Would love to hear your side and know if I can continue to eat beans in peace 🙂

  • When my (now ex) brother-in-law developed Crohn's disease, he was told to go on a low fiber diet, as fiber would irritate his gut. I had already convinced my (then) husband that a high fiber diet was good for you, and he tried to convince his brother to no avail. His brother has since had seven bowl resections and is in poor health. My ex-husband's doctor once told him, that if he had not changed his diet to a high fiber one, he too would have developed Crohn's.

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