Prebiotics are soluble fibers that feed beneficial bacteria and lead to an increase in those bacteria along with a decrease in potentially harmful bacteria. Prebiotics can be found in food, certain fiber supplements, and in prebiotic supplements (which are fiber supplements, by nature, although may not be labeled as such).

A recent study published in the journal Neurochemistry International found that the prebiotic FOS (fructooligosaccharide) increased levels of brain-derived neurotrophic factor (BDNF) in the hippocampus of the brain. BDNF has a calming effect on anxiety, and previous studies have found that the probiotic Bifidobacteria also increased BDNF.

“The increase of hippocampal BDNF after prebiotic intake is consistent with a probiotic effect, and may have been a direct consequence of elevated gut Bifidobacteria numbers,” noted the researchers.

This is yet more evidence of the gut-brain connection, a topic I blog about often because I find it fascinating. Although I have been studying this topic for years, it continues to amaze me that what goes on in the gut affects the rest of the body—including the mind! It makes so much sense. Our digestive tracts process just about everything that enters our bodies, taking what is useful and getting rid of what we don’t need. It’s a good thing we have an army of bacteria in our guts to help get the job done. We now know that army—which outnumbers our own cells 10 to 1—plays more of a role on our health than we ever thought possible.

There will likely be human studies to follow that look at the effects of prebiotics on anxiety. The probiotic studies to date have proved interesting, and I am sure there will be more to follow. I’ll keep you posted as I learn more.