In a this revealing study, scientists were able to show that consuming a high fat diet could disrupt normal brain function by altering the bacteria in the gut. There is growing evidence that the ecosystem of bacteria that reside in our guts, referred to as “the microbiome,” plays a pivotal role in mental health. The scientists that conducted this study were interested in finding out if the “bad” gut bacteria typically linked to obesity and consuming processed, fatty foods, could alter behavior even in the absence of obesity.

To test this hypothesis, they transplanted the “bad” bacteria from mice fed a high fat, unhealthy diet to the guts of healthy mice previously fed a balanced, normal diet. Indeed, the healthy mice that received the “bad” bacteria subsequently displayed numerous adverse mental changes including more anxiety, repetitive behaviors, and impaired memory. Additionally, the scientist noted that the brains of the mice transplanted with the “bad” bacteria showed significant increases in inflammation. (FYI, excess inflammation in the brain seems to be the key culprit in most all brain-based illnesses.)

This study adds to a growing volume of science directly linking the health of our brains and how we behave to the bacteria in our guts.

(Biological Psychiatry 77; doi: 10.1016/j.biopsych.2015.02.019)