Eating junk food when stressed out can trigger anxiety, finds study

Eating junk food like a samosa or burger when feeling stressed can actually elevate anxiety levels, researchers reported on Monday.
Researchers at the University of Colorado at Boulder found that in animals, a high-fat diet disrupts gut bacteria, alters behavior, and changes brain chemicals in ways that increase anxiety.
Christopher Lowry, a professor of integrative physiology at CU Boulder and lead author, remarked on the study's findings, published in the journal Biological Research."It's extraordinary to think that a high-fat diet alone could alter the expression of these genes in the brain," Lowry said. His research in animals suggests that exposure to an ultra-high-fat diet consisting of predominantly saturated fats, particularly at a young age, could both boost anxiety in the short-term and prime the brain to be more prone to it in the future.
The study showed that the high-fat diet group exhibited a molecular signature of high anxiety in their brains.
Researchers examined the animals' microbiome, or gut bacteria, throughout the study. Compared to the control group, the high-fat diet group not only gained weight but also showed significantly less diversity in gut bacteria.
This group also had higher expression of three genes involved in the production and signaling of the neurotransmitter serotonin, which is linked to stress and anxiety.
While serotonin is often called a "feel-good brain chemical," certain subsets of serotonin neurons can prompt anxiety-like responses when activated in animals.
Lowry suggests that an unhealthy microbiome may compromise the gut lining, allowing bacteria to enter the body's circulation and communicate with the brain via the vagus nerve, a pathway from the gastrointestinal tract to the brain.
"It makes sense from an evolutionary perspective," Lowry said. "We are hard-wired to notice things that make us sick so we can avoid them in the future."
Researchers noted that not all fats are bad. Healthy fats, such as those found in fish, olive oil, nuts, and seeds, can be anti-inflammatory and beneficial for the brain.