A high-fat diet may fuel anxiety

Recent research shows that feeding animals a high-saturated fat diet for nine weeks alters their gut bacteria, impacting brain chemicals and increasing anxiety. This study by the University of Colorado Boulder suggests that turning to junk food under stress may exacerbate rather than alleviate anxiety.

In the experiment, adolescent rats were split into two groups: one on a standard 11% fat diet and the other on a high-fat diet consisting of 45% fat, akin to typical American diets. The high-fat group gained more weight and showed reduced gut bacterial diversity, with increased Firmicutes and decreased Bacteroidetes levels.

Additionally, the high-fat diet group exhibited elevated expression of genes (tph2, htr1a, slc6a4) linked to serotonin production in the brainstem's stress-associated area, the dorsal raphe nucleus. This heightened molecular signature of anxiety was coupled with compromised gut health, potentially allowing bacteria to influence brain functions via the vagus nerve.

The researchers advised consuming healthy fats like those from fish and olive oil, prioritizing diverse fruits and vegetables, and limiting junk food intake to support both gut and brain health.