This landmark pilot study was the first clinical trial to investigate a ketogenic diet intervention as a therapy for serious mental illness since 1965. 21 participants with bipolar disorder or schizophrenia followed a ketogenic diet for 4 months. All participants were either also overweight or had metabolic abnormalities, such as insulin resistance or impaired glucose tolerance.
At trial completion, 79% of participants showed a clinically meaningful psychiatric improvement, including increased life satisfaction and enhanced sleep quality. While average psychiatric measures improved across all participants, greater adherence was associated with larger improvements, suggesting full adherence maximizes benefits. All participants who adhered to the diet were in recovery or a recovered state at the conclusion of the study, and 75% of participants overall were in recovery. Adherent individuals also experienced significant reductions in weight, BMI, waist circumference, and visceral adipose tissue alongside improvements in metabolic markers, such as decreased insulin resistance and triglyceride levels. All participants who met the criteria for metabolic syndrome at trial initiation were in remission by the end of the study.
These findings demonstrated the safety and feasibility of a ketogenic nutritional intervention in the treatment of serious mental illness.
