Impact of a ketogenic diet intervention during radiotherapy on body composition: III—final results of the KETOCOMP study for breast cancer patients

BACKGROUND: Obesity and low muscle mass are associated with worse outcomes of breast cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in breast cancer patients undergoing radiotherapy. METHODS: Patients with non-metastasized breast cancer were allocated to either the KD (N = 32) or the SD (N = 31) during radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters and quality of life were assessed before, during, and at the end of radiotherapy. RESULTS: ). Global quality of life remained stable in the SD group but increased in the KD group from a score of 66.7 to 75.0 (p = 0.20). CONCLUSIONS: In breast cancer patients undergoing curative radiotherapy, a KD based on natural foods is feasible. After initial water losses, the KD tends to reduce body weight and fat mass while preserving fat free and skeletal muscle mass. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02516501 , registered on August 06, 2015.