Gut Flora & Obesity

Gut Flora & Obesity
5 (100%) 11 votes

How one may be able to modify one’s own gut flora to facilitate weight loss.

Discuss
Republish

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Only one in ten of the cells in your body is human. The other 90% are bacteria; we have about 100 trillion of them on us, and in us. The human colon is considered the most biodense ecosystem in the world. We’re just like along for the ride. We exist as one big superorganism, in a mutually beneficial symbiotic relationship—usually.

Collectively, our gut bacteria weigh as much as one of our kidneys, and are as metabolically active as our liver. They affect our immune system; we just found out that if you give probiotics to kids, they don’t get sick as much. Our gut bacteria affect our hormonal balance, and they can affect our energy balance, as well. Is obesity linked to our gut flora?

There are some species of bacteria better at extracting calories from our feces than others. Pooped calories end up in the toilet, rather than on our hips. But there are certain obesity-associated bacteria with an increased capacity for energy harvest. Our bodies are trying to get rid of fecal matter, but certain bacteria in our colon can take our waste, break it down further, and release calories that are then absorbed back into our bloodstream. So here our body is trying to get rid of it all, and the calories are bouncing right back.

Now, this was originally all based on mouse studies, so we really didn’t know what to think. But finally, this year, we have some human data. And indeed, the type of bacteria in our guts is related to body weight, and weight gain.

That got some researchers in Austria thinking. Maybe one of the reasons vegetarians are so much slimmer, on average, is because their diets foster more of the lean-type bacteria, rather than the obese-type. And that’s exactly what they found.

They took a bunch of fecal samples from vegetarians, did some DNA fingerprinting, compared it to omnivore feces, and found significantly more of the lean-type bacteria—suggesting a smaller capacity for energy gain from food in vegetarians. How much smaller? Perhaps 2% of daily caloric intake.

That doesn’t sound like a lot, but it just happens automatically—while we sleep, even, and adds up over time. Over a year, that may come out to about five pounds of fat. And that may not sound like a lot, either, but that’s exactly how much people tend to put on annually during the midlife years.

So that could explain why, as we’ve gone over before, those eating vegetarian don’t seem to get that age-related weight gain that afflicts the rest of the population.

Please consider volunteering to help out on the site.

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Only one in ten of the cells in your body is human. The other 90% are bacteria; we have about 100 trillion of them on us, and in us. The human colon is considered the most biodense ecosystem in the world. We’re just like along for the ride. We exist as one big superorganism, in a mutually beneficial symbiotic relationship—usually.

Collectively, our gut bacteria weigh as much as one of our kidneys, and are as metabolically active as our liver. They affect our immune system; we just found out that if you give probiotics to kids, they don’t get sick as much. Our gut bacteria affect our hormonal balance, and they can affect our energy balance, as well. Is obesity linked to our gut flora?

There are some species of bacteria better at extracting calories from our feces than others. Pooped calories end up in the toilet, rather than on our hips. But there are certain obesity-associated bacteria with an increased capacity for energy harvest. Our bodies are trying to get rid of fecal matter, but certain bacteria in our colon can take our waste, break it down further, and release calories that are then absorbed back into our bloodstream. So here our body is trying to get rid of it all, and the calories are bouncing right back.

Now, this was originally all based on mouse studies, so we really didn’t know what to think. But finally, this year, we have some human data. And indeed, the type of bacteria in our guts is related to body weight, and weight gain.

That got some researchers in Austria thinking. Maybe one of the reasons vegetarians are so much slimmer, on average, is because their diets foster more of the lean-type bacteria, rather than the obese-type. And that’s exactly what they found.

They took a bunch of fecal samples from vegetarians, did some DNA fingerprinting, compared it to omnivore feces, and found significantly more of the lean-type bacteria—suggesting a smaller capacity for energy gain from food in vegetarians. How much smaller? Perhaps 2% of daily caloric intake.

That doesn’t sound like a lot, but it just happens automatically—while we sleep, even, and adds up over time. Over a year, that may come out to about five pounds of fat. And that may not sound like a lot, either, but that’s exactly how much people tend to put on annually during the midlife years.

So that could explain why, as we’ve gone over before, those eating vegetarian don’t seem to get that age-related weight gain that afflicts the rest of the population.

Please consider volunteering to help out on the site.

Doctor's Note

Check out these videos on gut bacteria:
Stool pH and Colon Cancer
Gut Feelings: Probiotics and Mental Health
Preventing Ulcerative Colitis with Diet
Carnitine, Choline, Cancer and Cholesterol: The TMAO Connection
The Leaky Gut Theory of Why Animal Products Cause Inflammation

And check out my other videos on weight loss

For some context, please check out my associated blog posts: Boosting Gut Flora Without Probiotics and How Probiotics Affect Mental Health.

If you haven’t yet, you can subscribe to my videos for free by clicking here.

15 responses to “Gut Flora & Obesity

Comment Etiquette

On NutritionFacts.org, you'll find a vibrant community of nutrition enthusiasts, health professionals, and many knowledgeable users seeking to discover the healthiest diet to eat for themselves and their families. As always, our goal is to foster conversations that are insightful, engaging, and most of all, helpful – from the nutrition beginners to the experts in our community.

To do this we need your help, so here are some basic guidelines to get you started.

The Short List

To help maintain and foster a welcoming atmosphere in our comments, please refrain from rude comments, name-calling, and responding to posts that break the rules (see our full Community Guidelines for more details). We will remove any posts in violation of our rules when we see it, which will, unfortunately, include any nicer comments that may have been made in response.

Be respectful and help out our staff and volunteer health supporters by actively not replying to comments that are breaking the rules. Instead, please flag or report them by submitting a ticket to our help desk. NutritionFacts.org is made up of an incredible staff and many dedicated volunteers that work hard to ensure that the comments section runs smoothly and we spend a great deal of time reading comments from our community members.

Have a correction or suggestion for video or blog? Please contact us to let us know. Submitting a correction this way will result in a quicker fix than commenting on a thread with a suggestion or correction.

View the Full Community Guidelines

  1. For vegans who don’t eat yogurt, what is a good source for probiotics? Probably not Kimchi, as you noted its harmful effects in another video!

    1. Commercial yogurt of any kind (soy, rice, cow, or coconut) is an insufficient source of the level of probiotic bacteria found effective in treating diarrheal illnesses, inflammatory bowel disease, and irritable bowel syndrome. A plant-based diet appears to naturally modulate one’s gut flora, but if you need to bring out the big guns for therapeutic usage or to repopulate your gut after a round of antibiotics, allow me to refer you to the advice of one of my medical mentors, Dr. Michael Klaper, who has some great probiotic tips and insight.

      1. Thanks for all of your information. But I was wondering, what about kefir grains? There are milk kefir grains and also water kefir grains used to ferment beverages. And do you know of any reliable comparison of yogurt and kefir, such as how many organisms are found in homemade yogurt and kefir? Thanks again.

  2. Dr. Greger, many thanks for your fine, concise, science based videos on so many subjects. My wife is battling stage 4 breast cancer. Due to the experience we’ve had I decided to put together a blog (stage4living.wordpress.com) to share resources I found that have helped my wife to save others from some of the distress we’ve experienced. Many of your videos dealing with cancer are posted on my blog.

    Here’s my question: I’ve probably heard over a hundred times people recommending the fruit and a tea (made from the leaves) of the soursop fruit tree. The common phrase is that it’s “10,000 times more powerful than chemo” (it’s even on YouTube). There’s clearly a bucket of hyperbole in that statement but I’m wondering if the sheer volume of people that place such faith in this magical fruit indicate that there’s at least some truth to the legends. Have you heard of any studies that shed some light of science on this legend? I’d appreciate your help in evaluating if it would be worth including this fruit (and tea from its leaves) in my wifes cancer management treatment plan.

    We are following predominately the integrative treatment system advocated by Dr. Keith Block (author of Life Over Cancer).

  3. Can you please help guide me for what are the best sources of probiotics? Pills, yoghurt, Kefir? It would be valuable to know this, short of going for a fecal transplant. Thanks!

  4. I’m posting here because I don’t know where else to go. I don’t have any plant based doctors in my area and I’m really struggling with the effects of this diet. I just can’t seem to lose any weight. I’m almost 30 years old, 5’8, 145lbs and I’ve been vegan for almost a year now. I’m being honest when I say that I’ve been eating as clean as possible this past year. High carb, low fat, lots of fruits/vegetables/whole grains, minimal processed food and oil (maybe 1-2 times a month), 1800-2000cals a day. I do 1 hour of yoga every day and 30-40 minutes of cardio 4 times a week. I haven’t lost a single pound. It’s really frustrating to be eating the healthiest diet on the planet and consistently working out without seeing any physical changes. I’ve also had a lot of stomach issues (gas, intense bloating, constipation which is crazy considering all the fiber I eat, etc.)

    My mom, who went vegan a couple of months after I did, has GAINED 40lbs. She’s in her early 50s, has never been overweight, and she walks/climbs stairs daily. I know this sounds crazy and it is! We are both so, so frustrated. I’ve read How Not to Die, I’ve read The Starch Solution. I don’t know what we’re doing wrong but it’s so discouraging. Not to mention really difficult to promote plant based eating when you’re gaining weight or unable to lose it. People are always commenting about my mom’s weight and telling her to go back to eating meat (which will never happen because we are both ethical vegans!) We’ve tried cutting out smoothies, cutting down on calories, eating more vegetables than carbs but nothing seems to work.

    I so want to be one of those people who magically loses 20 pounds on this diet but it’s just not happening. ANY suggestions or help would be greatly appreciated. Especially for my mom who has ALWAYS been slim, this has been a huge shock for her physically and emotionally.

  5. I had problems with my stomach so a naturepath recommended a stool test. And I had “bad” bacteria in them. They recommended probiotics to me and I took them. After I used all of the package I stopped taking them. And it started again after a while. Even though I was vegan for a while back then. So my doctor again (without testing my stool again) said to me I should take them again. I bought them and now I take half a package each day. But then I was afraid my stomach might rely on the bacteria instead of creating them itself. So I take them every 2 – 3 days. How long should I keep taking them? I hit a weight plateau for months now and I try to think of every little thing that might cause this.

    1. Saneesh,
      Thank you for your question. Yes, probiotics can provide many health benefits. Probiotics tends to be helpful only during the time you are taking them. You can improve your gut health even more by your overall diet. Please check out the following link for more information on probiotics https://nutritionfacts.org/topics/probiotics/ By eating a WFPB diet you will feed the healthy bacteria in your gut and greatly improve your digestive health and overall health as well.

Leave a Reply

Your email address will not be published. Required fields are marked *

Pin It on Pinterest

Share This