It sounds like science fiction, but it seems that bacteria within us — which outnumber our own cells about 100-fold — may very well be affecting both our cravings and moods to get us to eat what they want, and often are driving us toward obesity.
In an article published this week in the journal BioEssays, researchers from UC San Francisco, Arizona State University and University of New Mexico concluded from a review of the recent scientific literature that microbes 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.
Bacterial species vary in the nutrients they need. Some prefer fat, and others sugar, for instance. But they not only vie with each other for food and to retain a niche within their ecosystem — our digestive tracts — they also often have different aims than we do when it comes to our own actions
Following your gut takes on a whole new meaning as scientists find relationships between the brain and gut bacteria.
The next frontier of medicine isn’t in the depths of an Amazon jungle or in an air-conditioned lab; it’s in the rich and mysterious bacterial swamp of your gut. Long viewed as an enemy within, bacteria in the body have been subjected to a century-long war in which antibiotics have been the medical weapon of choice. But today, the scientific consensus about our body’s relationship with the trillions of microbes that call it home—collectively known as the microbiome—is changing dramatically. From potentially shaping our personalities to fighting obesity, the bacteria in our bellies play a much stronger role in our overall health than we once thought.
Developments in sequencing technology in the last decade have allowed scientists to better understand gut bacteria, and recent studies have shed light on how our digestive systems may mold brain structure when we’re young and influence our moods, feelings, and behavior when we’re adults. Scientists experimenting on mice have found links between gut bacteria and conditions similar to autism and anxiety in humans.
While it’s still early, the implications of better understanding how gut bacteria impacts our minds and bodies could change the way doctors treat myriad conditions, says Michael A. Fischbach, a microbiologist at UC San Francisco (UCSF). “If we use history as a guide, a lot of ideas probably won’t work out,” Fischbach says. “But even if one of them does, it’s a huge deal.”