Change your diet, change your gut bacteria?

Can certain diets help you lose weight by changing your gut microbes, as some people claim?

Two years ago, when researchers randomly assigned 609 overweight or obese people to healthy low-fat or low-carb diets for a year, both groups lost the same amount of weight (see more details about the study here).

Now scientists have gone back to look at the gut microbes of 49 of the participants.

The results: Microbes changed after 3 months on each diet, but neither those changes nor the participants’ original gut microbes predicted how much weight they lost after a year. And in both groups, gut microbes returned to their original state within 6 months, even though most participants stayed on their diets.

What to do: Until we know more, be skeptical of claims that diets—or probiotics—can change your gut over the long term.

Photo: nobeastsofierce/

The information in this post first appeared in the May 2020 issue of Nutrition Action Healthletter.

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