Gut Microbes Influence Binge-Eating of Sweet Treats in Mice


We have all been there. You just meant to have a single Oreo as a snack, but then you find yourself going back for another, and another, and before you know it, you have finished off the entire package even though you were not all that hungry to begin with.

 

But before you start feeling too guilty for your gluttony, consider this: It might not be entirely your fault. Now, new research in mice shows that specific gut bacteria may suppress binge eating behavior.

 

Oreos and other desserts are examples of so-called “palatable foods”—food consumed for hedonistic pleasure, not simply out of hunger or nutritional need. Humans are not alone in enjoying this kind of hedonism: Mice like to eat dessert, too. Even when they have just eaten, they will still consume sugary snacks if available.

 

The new Caltech study shows that the absence of certain gut bacteria causes mice to binge eat palatable foods: Mice with microbiotas disrupted by oral antibiotics consumed 50 percent more sugar pellets over two hours than mice with gut bacteria. When their microbiotas were restored through fecal transplants, the mice returned to normal feeding behavior. Further, not all bacteria in the gut are able to suppress hedonic feeding, but rather specific species appear to alter the behavior. Bingeing only applies to palatable foods; mice with or without gut microbiota both still eat the same amount of their regular diet. The findings show that the gut microbiota has important influences on behavior and that these effects can be modulated when the microbiota is manipulated.

 

The study was led by graduate student James Ousey in the laboratory of Sarkis Mazmanian, Luis B. and Nelly Soux Professor of Microbiology. A paper describing the research appears in the journal Current Biology on November 29.

 

“The gut microbiome has been shown to influence many behaviors and disease states in mouse models, from sociability and stress to Parkinson’s disease,” Mazmanian says. “The recent appreciation that feeding behaviors, driven by motivation, are subject to the composition of the gut microbiome has implications not just to obesity, diabetes, and other metabolic conditions but perhaps to overuse of alcohol, nicotine, or illicit substances that bring pleasure.”

 

Read more on the TCCI for Neuroscience website