UC San Diego trial finds ketogenic therapy may help anorexia nervosa

A supervised ketogenic therapy trial at UC San Diego put a medical version of keto to the test in anorexia nervosa, and the early signal was strong enough to matter. The first pilot clinical trial of its kind studied adults with weight-normalized or mildly underweight anorexia nervosa using a high-fat, low-carbohydrate, moderate-protein diet designed to maintain weight, not trigger the kind of rapid loss people associate with DIY keto.

The 14-week study was published June 3, 2026 in Communications Medicine. Of 22 enrolled participants, 18 completed the program, an 82% completion rate. No significant weight loss was observed during treatment. By the end of the trial, 72% of completers no longer met criteria for anorexia nervosa. Depression scores improved in every completer, and 72% reached the normal range for depression. Mild side effects were reported in 40% of participants, but those effects resolved by the end of the study.

That combination of feasibility, adherence, and clinical improvement is notable because anorexia nervosa remains one of the deadliest psychiatric illnesses. Even after weight restoration, symptoms often persist and can drive relapse. UC San Diego’s researchers said the trial builds on earlier case studies and a prior pilot study, with the goal of learning whether nutritional ketosis can target the neurometabolic dysfunction that may sit underneath the disorder.

Guido Frank, MD, professor of psychiatry at UC San Diego School of Medicine, led the work with support from a philanthropic gift from Baszucki Group. Frank has spent more than 25 years studying eating disorders, and his team has framed the research as part of a broader push to find new treatment options for patients who still struggle after standard care. The study focused on adults in San Diego and La Jolla, California, through UC San Diego’s eating-disorders program.

The research line is growing. UC San Diego’s clinical-trials listings show a separate 14-week partial hospitalization and intensive outpatient study aiming to recruit 60 people with anorexia nervosa, comparing therapeutic ketogenic diet with treatment as usual. Other studies in the program are also looking at brain metabolism and persistent psychopathology.

For the keto community, the takeaway is clear: this was not a casual low-carb experiment. It was supervised clinical treatment, and the first pilot data suggest therapeutic ketosis may deserve a serious place in the conversation about anorexia nervosa.