This is scientific Americans 60 Second Science.

I'm Karen Hopkins.

We all know that stuffing our faces with sweet treats is not good for us.

In part, because it's bad for the health-promoting bacteria that

inhabit our intestines. Now, researchers have figured out how simple sugars wipe out

a particular strain of beneficial gut microbes.

The underlying assumption that exists... particular strain of beneficial gut microbes.

The underlying assumption that existed in the literature was that simple sugars such

as fructose and sucrose, which are prevalent in the Western diet, are not good for humans.

Yale Professor of Microbial Pathogenesis,

Eduardo Grosman, who led the study.

Simple sugars like those in high fructose corn syrup,

or the table sugar formerly known as sucrose

were thought to be absorbed in the small intestine so a lot of our gut

bacteria would never actually be exposed to them because fiber and complex

carbs made of long chains of sugar molecules, are harder to

digest. They make it all the way to the large intestine, where they promote the growth of good

bugs, like bacterioidis, theta iota omicron, a microbe found in individuals who are healthy and lean.

But now what our work actually shows is that both sfructos and sucrose do make it to the column where the microbiota exists,

and second, that these sugars impact a good bacterium even though nutrition is not involved.

In other words, the bacteria are not using fructose and sucrose as food.

Instead, the sugar serve as signals that shut down the production of a protein that beneficial

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