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."