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Pathogen from gut of obese human causes obesity in germfree mice

nature.com

11–20 of 135 posts

Re: Pathogen from gut of obese human causes obesity in germfree mice

#11
ISME Journal.

1. Two independent facts from the experiment: A pathogen that causes obesity (in mice) seems to be active in some obese humans.

2. Severely restricted diet seems to powerfully reduce the population of this organism.

I doubt that these facts are unrelated. It's classic host-parasite behavior. The pathogen depends on high calorie intake in its host, and therefore engineers that behavior (somehow).

Further there is no reason to make the leap that the only or best way to counter this pathogen is through diet. It's not impossible that a targeted antibiotic that eliminates this pathogen would have an effect on the body composition of the host.

Re: Pathogen from gut of obese human causes obesity in germfree mice

#12
post #5

The article is very interesting. I looked, but couldn't find information on the exact diet of the test subject during the study. Did anybody else have any better luck?

The supplementary information link at the bottom has a link to the diet and how it was prepared: Dietary intervention and sampling. This volunteer was given a diet composed of whole grains, traditional Chinese medicine and prebiotics (WTP diet) for intervention. He was given 4 cans of gruel per day as staple food contract prepared in the form of cooked porridge (370 g wet weight per can) then canned by a food manufac…

Is it just me or isn't that basically what they feed you in the Matrix?

"Tank: Here you go, buddy; 'Breakfast of Champions.' Mouse: If you close your eyes, it almost feels like you're eating runny eggs. Apoc: Yeah, or a bowl of snot. Mouse: Do you know what it really reminds me of? Tasty Wheat. Did you ever eat Tasty Wheat? Switch: No, but technically, neither did you. Mouse: That's exactly my point. Exactly. Because you have to wonder: how do the machines know what Tasty Wheat tasted like? Maybe they got it wrong. Maybe what I think Tasty Wheat tasted like actually tasted like oatmeal, or tuna fish. That makes you wonder about a lot of things. You take chicken, for example: maybe they couldn't figure out what to make chicken taste like, which is why chicken tastes like everything. Apoc: Shut up, Mouse."

http://www.imdb.com/title/tt0133093/quotes?qt0324288

Re: Pathogen from gut of obese human causes obesity in germfree mice

#13
I can comprehend a good deal of code but this medical jargon is making my head spin. Anyone care to summarize this for us feeble minded laypersons? Because it sounds like they found something in obese people that if eliminated could lead to weight loss. I know there are people that can benefit from that when extreme obesity makes regular, "simple" dieting very challenging and exercise impossible.

Re: Pathogen from gut of obese human causes obesity in germfree mice

#14
post #9

Ok, this is an interesting observation: "After 9 weeks on the WTP diet, this Enterobacter population in the volunteer's gut reduced to 1.8%, and became undetectable by the end of the 23-week trial" So the thesis is that this bacteria lives in obese people's gut, and it makes them more obese. But once they diet to a point where they are not obese, the bacteria dies off? I wonder if they are going to try a diet + anti-…

For people who didn't read the summary - that patient who lost 30kg and reduced their bacteria population was on anti-biotics. So, right, it would be interesting to see if that bacteria reduces without the anti-biotics.

But before you think the researchers left a big hole in their research, remember that the addition of bacteria makes mice obese. Now if we could just try that on humans...

edit: As pdx points out below, not antibiotics, pre-biotics. Big difference.

Re: Pathogen from gut of obese human causes obesity in germfree mice

#16
Someone made a comment yesterday on another site about how we are still living in the bacterial age.

It's a strange notion, that bacteria still own the earth, but we are host to more bacteria than we are our own cells. It's such an interesting yet scary thing to think about - does higher order life exist solely as vessels for bacteria propagation?

Re: Pathogen from gut of obese human causes obesity in germfree mice

#17

I can comprehend a good deal of code but this medical jargon is making my head spin. Anyone care to summarize this for us feeble minded laypersons? Because it sounds like they found something in obese people that if eliminated could lead to weight loss. I know there are people that can benefit from that when extreme obesity makes regular, "simple" dieting very challenging and exercise impossible.

tl;dr: fat guy lost a ton of weight by a diet that reduced a specific kind of gut bacteria; this bacteria inserted into mice engineered to be thin caused the mice to gain weight.

Ergo, bacteria may be driving obesity.

Re: Pathogen from gut of obese human causes obesity in germfree mice

#18
Gut bacteria are an extremely powerful system within our bodies and are mostly still mysterious to us. Imbalances of one type or another lead to large amounts of bacterial toxins being introduced to the intestine and the bloodstream, with wide-ranging mental and physical effects. I'm not surprised that contribution to obesity is among them.

It works kind of like this:

You eat too much refined/processed food, that is high in sugars of any kind, especially complex polysaccharides and the food is not fully digested by your stomach + small intestine, and ends up in your large intestine. This surplus of sugars provides abundant food to your billions of gut bacteria, and they start to grow out of control, and mutate. Those mutated bacteria now dump their toxic waste by-products into your body.

Following restricted diets that are intended to reduce the food supply to your gut bacteria colonies is a valid and often the only successful way to treat the conditions caused by this influx of bacteria and toxins.

Antibiotics of any kind are simply too broad a weapon - they will attempt to eliminate everything which will result in other imbalances. The food we eat every day is the most important factor for intestinal and therefore overall health...

[1] This book is helpful: http://www.breakingtheviciouscycle.info

Re: Pathogen from gut of obese human causes obesity in germfree mice

#19
post #11

ISME Journal. 1. Two independent facts from the experiment: A pathogen that causes obesity (in mice) seems to be active in some obese humans. 2. Severely restricted diet seems to powerfully reduce the population of this organism. I doubt that these facts are unrelated. It's classic host-parasite behavior. The pathogen depends on high calorie intake in its host, and therefore engineers that behavior (somehow). Further…

Very interesting observation re parasitic behavior. I suspect that with modern food processing techniques to make food relentlessly cheaper, we have unwittingly enhanced the food supply for the parasite.

Re: Pathogen from gut of obese human causes obesity in germfree mice

#20
post #6

Earlier quoted context omitted.

So, only 1344 cals per day.

One can argue it was the calorie restriction and not the bacteria. However, the interesting part was that the pathogen then caused the mice to gain weight.

Probably because it made the subjects want to eat more. There's no magic bullet for gaining or losing weight, you either eat more or less that your body needs.
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