Could the bacteria in your stomach be making you fat? Studies point to a specific microbe that causes the body to hoard calories. A new test can reveal if you have it, and now researchers are looking to a common medicine as a possible fix.

Researchers at Cedars-Sinai have found that breath can tell them a lot about what kind of microbes are living in the gut.

All sorts of little critters, said Dr. Ruchi Mathur, diabetes specialist with Cedars-Sinai. The majority of those are housed in the GI tract and they help us harvest nutrition, they help us digest food.

Researchers are specifically looking at a microbe called Methanobrevibacter smithii.

So we think the microbe is working to increase calorie intake from foods that we consume, said Mathur. We think it does it by increasing calorie harvest that the other microbes in the gut are receiving, and also by slowing intestinal transit.

These microbes produce a lot of methane and hydrogen, so if there is a high amount of those gases in the breath, that s a telltale sign that this microbe is present and may be causing weight gain.

They tend to have a higher BMI or body mass index, and a higher percentage of body fat, said Mathur.

Denise Hannagan is active, eats healthy foods, but she s been gaining weight rapidly.

It was quite a bit. It s been 20 pounds over two years, so that s significant to me, she said.

So she took the breath test.

I was kinda shocked that I was positive, she said.

Now she s participating in a trial to see if antibiotics will make a difference.

We think that we might be able to help some people who have this microbe, eradicate it and perhaps lose a bit of weight, said Mathur.

I hope that I would lose weight, and keep the diabetes away from my diagnosis, added Hannagan.

Researchers caution that it s much too early to recommend antibiotics for weight loss, but the finds may help explain why some people can t seem to shed the excess pounds.

Dr. Mathur's study is published in the Journal of Clinical Endocrinology & Metabolism.

Read or Share this story: