Symptom impact and safety of ketogenic therapy in adults with anorexia nervosa: a feasibility trial

BACKGROUND: Anorexia nervosa (AN) is a severe psychiatric disorder characterized by food restriction and significantly low body weight. Even after weight restoration, core symptoms such as body dissatisfaction, intense fear of eating, and preoccupation with body shape and weight often persist, contributing to a high risk of relapse. METHODS: This study evaluated the feasibility and safety of a weight-maintaining ketogenic dietary therapy administered over 14 weeks in adults with anorexia nervosa who were either mildly underweight or weight-restored. The study also examined whether ketogenic therapy could reduce eating disorder symptoms. Twenty-two individuals participated, and eighteen (82%) completed the trial. RESULTS: Repeated-measures MANCOVA (intent-to-treat; comorbidity and medication included in the model) reveals significant overall treatment effects (Wilk's λ = 0.165, F = 2.383, p < 0.001), and symptom score decreases over time on the Eating Disorder Examination Questionnaire (EDE-Q) subscales Restraint, Eating Concern, Shape Concern, and Weight Concern, as well as for depression scores. At study completion, 72% of participants show EDE-Q and depression scores within the normal range. At three-month follow-up, 39% of completers continue ketogenic dietary therapy, of whom 28% show an increase in EDE-Q Global scores, while among those not maintaining ketogenic therapy, 64% present with an elevation in EDE-Q scores. Ketogenic dietary therapy does not precipitate worsening of symptoms or clinically significant weight loss. CONCLUSIONS: The ketogenic dietary therapy is well-tolerated and demonstrates potential efficacy in reducing core symptoms of AN among adults who are mildly underweight or weight-restored. These findings support the further investigation of ketogenic dietary therapy as a potential intervention for this population. CLINICALTRIALS: gov ID: NCT06000774; Registration Date August 14, 2023.