Gut instincts

We’ve often been told that our “gut instincts” can guide us to a decision. That saying may be more true than we ever thought. Researchers from three U.S. universities recently conducted a review of scientific literature and concluded that our guts may indeed tell us what to do–at least when it comes to eating. The researchers determined that microbes living in our digestive system “influence human eating behavior and dietary choices to favor consumption of the particular nutrients they grow best on, rather than simply passively living off whatever nutrients we choose to send their way.”

So it seems that the voice in your head telling you to eat doughnuts might be coming from your gut instead. While the exact mechanism has yet to be determined, there are several hypotheses about how this community of microbes, collectively known as the gut microbiome, influences our behavior. Microbes may “influence our decisions by releasing signaling molecules into our gut. Because the gut is linked to the immune system, the endocrine system and the nervous system, those signals could influence our physiologic and behavioral responses.” These signals may change our taste receptors, produce toxins to make us feel bad, or release chemical rewards that make us feel good, according to Athena Aktipis, PhD, of the University of Arizona.

Fortunately this communication appears to be a two-way street, so we don’t have to be held hostage by our bacteria. While microbes may be telling us what they want, we can change the level of microbes to suit our desires as well. According to Carlo Maley, PhD, of the University of California, we “can influence the compatibility of these microscopic, single-celled houseguests by deliberating altering what we ingest, with measurable changes in the microbiome within 24 hours of diet change.”

The potential for this discovery is exciting researchers. Says Aktepis: “Targeting the microbiome could open up possibilities for preventing a variety of disease from obesity and diabetes to cancers of the gastro-intestinal tract. We are only beginning to scratch the surface of the importance of the microbiome for human health.”