Feeling Stressed? Skip the Fries: High-Fat Diet Linked to Anxiety

We all know the urge to reach for comfort food when stress hits. But new research suggests that greasy burgers and fries might not be doing us any favors. In fact, a high-fat diet could actually worsen anxiety, according to a study published in Biological Research.

Previous research has shown that switching to a healthier diet can improve mental health by reducing the risk of depression and anxiety. This new study delves deeper, exploring the reasons behind the connection between a high-fat diet and anxiety.

The researchers found that a high-fat diet disrupts the gut bacteria in animals. This disruption, through a complex gut-brain connection, influences brain chemicals in a way that contributes to anxiety and other behavioral changes.

In a previous study, the same researchers discovered that rats fed a high-saturated-fat diet displayed signs of anxiety and inflammation in the brain.

“We all know these aren’t the healthiest foods,” said lead author Christopher Lowry in a press release. “But if you consider that they also impact your brain in a way that can promote anxiety, that raises the stakes even higher.”

The nine-week study divided rats into two groups. One group received a normal diet with around 11% fat, while the other received a high-fat diet with 45% fat, primarily from animal products. (For reference, the average American diet is about 36% fat, according to the Centers for Disease Control and Prevention.)

The researchers monitored the rats’ weight, gut bacteria, and behavior throughout the study. As expected, the high-fat group gained more weight and showed less diversity in their gut bacteria, indicating poorer gut health. Interestingly, there was an increase in a type of bacteria called Firmicutes and a decrease in Bacteroidetes. This imbalance is often linked to unhealthy Western diets and obesity.

“The high-fat diet group also showed increased activity in three genes involved in the production and signaling of serotonin,” the press release stated. Serotonin is often called a “feel-good” chemical, but some serotonin neurons, when activated, can trigger anxiety-like responses in animals.

“The fact that a high-fat diet can alter the expression of these genes in the brain is quite remarkable,” explained Lowry. “The high-fat group essentially had the molecular signature of a high anxiety state in their brains.”

The Takeaway:

This research suggests that a high-fat diet can have negative consequences beyond physical health. It may also contribute to anxiety by disrupting gut bacteria and influencing brain chemistry. So next time you’re feeling stressed, consider reaching for a healthier option instead of comfort food. Your brain (and your gut) will thank you for it!