Nutrition & Diet

Cutting Ultra-Processed Foods Significantly Eased Depression in Small Trial

A small but carefully designed UC San Francisco study published in JAMA Psychiatry found that people with depression who cut ultra-processed food intake by more than 85% showed moderate to large improvements across three depression measures, with modest anxiety reductions as well. The 20 participants, averaging 44 years old and all carrying at least one metabolic condition, followed either their usual diet or a low-ultra-processed-food diet for four weeks, then switched. Researchers believe the gut-brain axis is a key mechanism: ultra-processed foods may damage the gut lining, triggering chronic low-grade inflammation that worsens or causes depression. While preliminary, the findings support a larger phase 2 trial planned for 2028 and add to growing evidence that diet quality directly influences mental and metabolic health.