Recent research from the University of Colorado Boulder suggests that consuming a high-fat diet can negatively impact gut bacteria and brain chemistry, potentially increasing anxiety. The study involved adolescent rats on diets with differing fat content and analyzed changes in their microbiomes and behavior.
Lowry’s team divided adolescent rats into two groups: Half got a standard diet of about 11% fat for nine weeks; the others got a high-fat diet of 45% fat, consisting mostly of saturated fat from animal products. The high-fat diet group also showed higher expression of three genes involved in the production and signaling of the neurotransmitter serotonin—particularly in a region of the brainstem known as the dorsal raphe nucleus cDRD, which is associated with stress and anxiety.
“If you think about human evolution, it makes sense,” Lowry said. “We are hard-wired to really notice things that make us sick so we can avoid those things in the future.”