Background: Anorexia nervosa is a devastating condition that increases risk of death over five-fold and is associated with a high rate of relapse. Considering the growing field of metabolic psychiatry, anorexia can be framed as a ‘metabolic-psychiatric’ condition that may benefit from treatment with metabolic health interventions with neuromodulatory properties. Ketogenic diets, very low carbohydrate high-fat diets, are one such neuromodulatory intervention with a long history of use in epilepsy and more recently in other systemic, neurological and mental health conditions.Aim: To describe clinical cases that highlight the potential of ketogenic diets in the treatment of anorexia and the need for further research.Setting: Patient interviews were conducted via telemedicine.Methods: Medical interviews and chart reviews were conducted with three patients with severe anorexia. Written informed consent was provided by all participants.Results: Patients with anorexia, body mass index (BMI) nadirs of 10.7 kg/m2, 13.0 kg/m2 and 11.8kg/m2 and refractory to standard of care therapy, each achieved remission of between 1–5 years to date on a high-fat animal-based ketogenic diet. Patients exhibited not only improvements in weight, with weight gain of over 20 kg each, but also diminution of anxiety and overall enhanced mental well-being.Conclusion: These cases suggest a ketogenic diet may be useful for some patients with anorexia. Further research is needed.Contribution: This case series is the first to document treatment of anorexia with unimodal ketogenic diet intervention and raises provocative questions about the role of this neuromodulatory dietary treatment for patients with anorexia, as well as the neurometabolic nature of the disease itself.