Specific Gut Bacteria May Account For Much Obesity

resistant writes "A limited study from China offers the tantalizing possibility that targeting specific gut bacteria in humans could significantly reduce the scope of an epidemic of obesity in Western countries: 'The endotoxin-producing Enterobacter decreased in relative abundance from 35% of the volunteer's gut bacteria to non-detectable, during which time the volunteer lost 51.4kg of 174.8kg initial weight and recovered from hyperglycemia and hypertension after 23 weeks on a diet of whole grains, traditional Chinese medicinal foods and prebiotics.' As usual, sensationalist reports have been exaggerating the import of this very early investigation, and one wonders about that 'diet of whole grains.' Still, there could be meat in the idea of addressing pathogenic bacteria for the control of excessive weight gain. After all, it wasn't too long ago that a brave scientist insisted in the face of widespread ridicule that peptic ulcers in humans usually are caused by bacterial infections, not by acidic foods."

Comments

Mass-Media Report

[resistant]

In retrospect, I guess it couldn't hurt to mention at least one mass-media report that doesn't seem too excitable:

Researchers in Shanghai identified a human bacteria linked with obesity, fed it to mice and compared their weight gain with rodents without the bacteria. The latter did not become obese despite being fed a high-fat diet and being prevented from exercising. The Shanghai team fed a morbidly obese man a special diet designed to inhibit the bacterium linked to obesity and found that he lost 29 per cent of his body weight in 23 weeks. The patient was prevented from doing any exercise during the trial. Prof Zhao said such a loss in an obese patient using this diet was unprecedented. The patient also recovered from diabetes, high blood pressure and fatty liver disease.

It will be fascinating to see what happens when other teams try to replicate these results with larger, more statistically significant groups than just one individual. ^^;

Re:Mass-Media Report

[Samantha Wright]

This has actually been studied quite extensively in the last few years, mostly by American researchers. They've been able to show how that mice fed samples of this bacterium will gain weight drastically. Basically, the bacteria process certain sources of food that we're bad at absorbing and make it easier for us to absorb them. It's believed that there's an immunological mutation (which is otherwise all but harmless) that lets them proliferate excessively in humans (defence against flagella, I think), so one can actually say that obesity is genetic, albeit indirectly so.

But that all being said, while careful diet control is certainly effective for mitigating digestion-related problems, this study isn't a cure so much as a band-aid. I'm pretty sure anyone would lose weight and eliminate unwanted intestinal flora under the intake suggested.

Re:Mass-Media Report

[fyngyrz]

Gut bacteria? Nein, nein, das ist schlechte bacteria!

Re:I though it was over consumption of cals.

[MickyTheIdiot]

Why is everyone here in the US hooked on the "false dillema" falicy?

Why can't there be multiple issues? We do have the people that overeat, but there's more that a few people that have had problems with obesity and no one quite understands what the real cause is. There can always be multiple causes and multiple solutions (or not one single solution).

Re:I though it was over consumption of cals.

[newcastlejon]

Why are people hooked on the "false dillema" falicy?

FTFY. Please, let's try and have at least one science article free of politics and anti-$country rhetoric.

Re:I though it was over consumption of cals.

[rabtech]

Why is everyone here in the US hooked on the "false dillema" falicy?

Why can't there be multiple issues? We do have the people that overeat, but there's more that a few people that have had problems with obesity and no one quite understands what the real cause is. There can always be multiple causes and multiple solutions (or not one single solution).

It's more than just that. Controlled studies where volunteers spent a couple weeks locked in a research facility eating only the precisely measured meals given to them by researchers showed variations in weight gain/loss, even after accounting for muscle mass, overall health, and amount of exercise the volunteers engaged in. Some participants lost weight, some stayed relatively the same, and some gained weight.

A persistently (and severely) restricted diet will eventually overcome all other factors and force you to lose weight, but it is obvious that some people absorb way more calories from the same meal than others. If the gut bacteria are breaking down certain complex carbohydrates, starches, etc that would otherwise go undigested, they could easily account for the difference.

In fact, in a famine or food-poor situation, such bacteria would be evolutionarily selected for, as they would give the carriers a leg-up, allowing them to stay healthy and non-malnurished while their neighbors starved.

Good plan, but not for those results

[fyngyrz]

You know, that doesn't work for everyone. It sounds great when it works for YOU, but it's entirely possible to eat reasonably, exercise a lot, and *still* not lose weight. I exercise five days a week, two hours a day, and I'm not talking light exercise. I don't eat sweets, I don't drink, I control my carbs, I make sure I don't drown in meat proteins... I *love* veggies and eat them every day, both salads and side dishes, and I *still* have trouble controlling my weight. Yeah, I'm strong and have stamina and flexibility -- all important targets for my undertakings -- but the fat wants to hang around regardless. I have *never* been "cut." Kinda sleek looking like a seal back in my teenage days, pretty big through the chest and shoulders, but even then I carried extra weight (i'm talking fat) on my thighs and ass. And I was active as hell. Caving, swimming, martial arts, biking, dragging musical equipment from gig to gig, rope climbing, pushing lawn mowers... I hardly ever sat still.

Today I have students that are so cut, so defined, so obviously on the extreme low end of the body fat range it would make you cry... and if that didn't do it, watching them wolf down $15 worth of McDonald's poison surely would. I can't eat that crap at *all* or my weight takes right off. Not that I really want to, but still, the message is clear: What makes me fat doesn't make you fat, and so forth.

Everyone's experience is not the same. Metabolism, infection, allergies, immune system fuckarows and Darwin knows what else...

"Exercise and eat healthy food" is not a universal prescription for "control body fat." It's just a good start for baseline health.

I wouldn't be the least bit surprised if someone identifies one (or more) independent factors that drive fat retention. I've suspected it for years.

Re:Calories?

[eWarz]

This is false. My wife can eat 1200 calories on a given day and still gain weight. I can eat 3500 calories in a day and still lose weight. The issue is the level that your body is able to break down certain foods. Example: Eat a 2000 calorie meal. Just because the meal is 2000 calories doesn't mean that 2000 calories go into your body. Certain fats, proteins, etc. don't break down in each person the same way. One person might get 1800 calories from that meal, another person 1300. Also, insulin levels and the like prevent you from burning fat.

Re:I though it was over consumption of cals.

[Rich0]

Uh, if you actually extracted all the mass-energy of a french fry with 100% efficiency you could wipe out a city with the fire coming out of your mouth...

Since your digestive system is somewhat less efficient than an active galactic nucleus, you'll have to settle for a few paltry calories, and the number will vary by individual.