Posted on 09/06/2013 11:44:52 AM PDT by neverdem
What makes some people slender and others full-figured? Besides diet and genetics, the community of microbes that lives inside us may be partially responsible. New research on twins suggests that lean people harbor bacteria that their obese counterparts don't have. And, given the chance, those bacteria may be able to prevent weight gain. But don’t dig your skinny jeans out of the closet just yet. So far, the work has been done only in mice. What's more, the bacterial takeover requires a healthy, high-fiber diet to work, illustrating the complex relationship between diet, microbes, metabolism, and health.
Our intestines are home to at least 400 species of bacteria, and evidence is building that the balance of microbes in our internal ecosystem has far-reaching effects on health, including brain function and risk of cancer. A study last year showed that transferring gut bacteria between humans reduced insulin resistance, which is linked to obesity.
To explore how microbes differ between obese and lean people, researchers at Washington University in St. Louis took gut bacteria from four pairs of identical and fraternal twins; one sibling in each pair was lean and the other obese. Then they transplanted these microbes into mice that had no intestinal microbes of their own. The mice who got microbes from the lean twins stayed lean, the researchers report today in Science. Those that got microbes from the obese twins increased their body fat by 10% on average, even though they were eating the same amount of food.
What would happen if these two sets of microbes got mixed up in the gut, the researchers wondered. Led by microbiologist Jeffrey Gordon and graduate student Vanessa Ridaura, the team took advantage of one of the rodents' least endearing habits: They eat each other's poop. After letting this happen, the researchers discovered that microbes from the lean twins seemed to be particularly good at taking hold in the gut ecosystems of the mice that started with obesity-associated microbes. And after those bacteria moved in, the mice didn't gain weight. The most invasive species of microbes from the thin animals were in the Bacteroidetes group, which has previously been associated with leanness in mice and humans. The obese mice seemed to have unoccupied niches that the Bacteroidetes could easily move into.
To figure out what the gut bacteria might be doing, the researchers looked for bacterial genes that were active in the two kinds of mice. The heavier mice had higher levels of proteins involved in detoxification and stress responses; the lean mice expressed more genes involved in breaking down dietary fiber.
Diet, it turns out, was key to the impressive properties of the microbes from the lean twins. All the mice in the first round of experiments had been eating chow that was high in fiber and low in fat. The researchers then prepared a mouse-pellet form of an unhealthy human diet, high in fat and low in fiber, and housed svelte and heavy mice together again. They found that, with this diet, the microbes associated with leanness didn't colonize the cagemates’ intestines.
This work was rigorously done and fits in well with earlier findings, including the idea that Bacteroides may protect against weight gain, says Alan Walker, a gut microbiologist at the Wellcome Trust Sanger Institute in the United Kingdom who was not involved in the study. What's new here, he says, is that the researchers began addressing the question of how that protection might work: which species are responsible, what genes they use, and what diet they require.
"This study is an important step toward ultimately answering these questions," says microbiologist Peter Turnbaugh of Harvard University. A valuable result of this work, they both agree, is that it sets up a way to test the effects of microbial therapies on human gut bacteria (even though the bugs are living in a mouse). The authors suggest that a logical next step is to use the animals to measure the effects of particular foods or ingredients on gut ecosystems.
The mouse experiments also provide a way to test fecal transplants, which can cure a potentially fatal intestinal infection in humans and show potential for treating other conditions such as inflammatory bowel disease and obesity. There's a danger inherent in this approach: Transferring human feces into a patient's colon runs the risk of transmitting pathogens as well. Walker and the authors note that a well-tested "next-generation probiotic" consisting of known beneficial microbes delivered as a pill or other therapy could take the place of fresh feces, and this mouse system provides a way to identify the most effective bacteria, the diseases those bacteria can treat, and whether a particular diet is necessary.
"There's a major way to go before you can translate these results to humans," Walker cautions. A weight-loss probiotic isn't a simple next step, as the researchers found when they isolated 39 of the beneficial Bacteroidetes species. The mixture was unable to cause the same effects as mouse poop, possibly because the Bacteroidetes aren't acting alone and more of the microbial players need to be identified.
Ping
don’t hang out with fat rodents.
So I should eat skinny people’s poop?
Is Slim Whitman contagious?..............
Or we could eat veggies and go for a walk for a lot less money.
Their assumption that high-fat, low-fiber diets are unhealthy in humans is contradicted by numerous studies - and supported by numerous others.
That some people do well and others do not on a low-fat diet and some do well and others do not on a low-carb diet is well-established, but the whys and wherefores are not.
Could it be that the strain of bacteria they claim promotes health and leanness that only thrive on a low-fat diet only does so on a low-fat diet, and that there is a different strain of bacteria that promotes health and leanness that only thrives on a low-carb diet?
And maybe the reason we see the differences in how people respond to different diets is partly a matter of which strains of bacteria are established in their gut?
Of course, parasites — i.e., a tapeworm — can make one skinny.
Are the probiotics I hear about considered the same thing as the “good bacteria” which can help one slim down?
I would recommend against that.
I finished the article which answered my question: “A weight-loss probiotic isn’t a simple next step, as the researchers found”
Silly question. The amount of food (particularly fat-filled garbage) versus the amount of exercise (and, playing video games doesn't count!).
Today, I'm gratefull that my mom used to make me turn off the electronic babysitter (TV) and go outside and play. I consider it the main reason that I'm not a blubberball, but just slightly overweight for my age (or, perhaps, I'm a little under tall - depends on your perspective!).
Fat peeps need to get a poop transplant from skinny peeps?
If you have to eat somebody’s poop to catch something, I don’t know if that classifies as contagious.
Same here. My dad would kick us out of the house if he found us just slacking off. Or he would drag us to a gym for sports etc. Second, I work in Hollywood so it’s not good to look like a slob.
I seem to remember that the eggs of some intestinal worm were in fact marketed in a weight loss pill a hundred or so years ago.
You don’t have to eat poop to get the microbes. After all, producers do fine getting the probiotic organisms into our yogurt products. Will they develop a product to introduce the “skinny” microbes??
Eating poop is good for you. Who knew?
I subscribe to the Rodney Dangerfield theory: “If you want to look thinner, hang out with people who are fatter than you are.”
Just do a bunch of warm coffee enemas —gross, huh? It was discovered by the Germans in WW1, and was in the Merk catalogue until about 1972.
Also drink dilute shakes of bentonite clay and psyllium husk powder, 1 tbsp of the clay and 1 tbsp of the husk in a very tall glass of water.
Do that 2x daily for 3 months and you’re good.
Also do probiotics a lot —keifir, saurkraut, kim-chee.
Cheap, simple, effective.
You can get the clay (it’s a powder) super cheap at herbco.com in the clay section.
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