Two separate bodies of published research have reported associations between ultra-processed food consumption and adverse mental and cognitive health outcomes.

A study published in JAMA Psychiatry in September found that reducing ultra-processed food intake may improve depression symptoms. This finding aligned with an earlier trial published in the same journal in September 2025, which also observed an association between reduced ultra-processed food intake and improved depression outcomes in trial participants.

On 26 October 2026, a paper published in the American Journal of Public Health found higher ultra-processed food intake correlates with elevated cognitive impairment and dementia risk in older US adults.

Independent dietitian Michelle Routhenstein has stated that processing is not inherently negative. Many nutritious foods undergo some processing, Routhenstein noted.