AUTHOR=Worster Kate , Colgan Dana , Vita Alexandra , McClure Christine , Buttolph Lita , Hodges Romilly , Senders Angela , Erlandsen Andy , Elbarbry Fawzy , Zwickey Heather TITLE=A mixed methods feasibility study of a ketogenic diet as treatment for Parkinson’s disease JOURNAL=Frontiers in Nutrition VOLUME=Volume 12 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1601446 DOI=10.3389/fnut.2025.1601446 ISSN=2296-861X ABSTRACT=ObjectivePeople with Parkinson’s disease (PD) have been shown to benefit from a ketogenic diet (KD). However, evidence suggests the traditional KD’s high dairy consumption may exacerbate PD symptoms. This patient-initiated study assessed the feasibility and acceptability of a novel ketogenic diet limiting dairy products in patients with PD. Quality of life and functional movements were also evaluated.MethodsTwelve people with PD followed a modified, low dairy KD for 12 weeks. We provided support and nutritional education to assist with adherence. Subjects recorded daily food diaries, from which total macronutrients were calculated. Every 4 weeks blood (complete blood count (CBC), lipid panel, vitamin D, beta-hydroxybutyrate, electrolytes), urinalysis (calcium, creatinine), vitals, height, weight, quality of life [Parkinson’s Disease Questionnaire-39 (PDQ-39)] and functional movement assessments [Unified Parkinson’s Disease Rating Scale (UPDRS), Freezing of Gait, mini-Balance Evaluation Systems Test (mini-BEST), 360° Turn] were collected.ResultsAll subjects completed the study and 75% recorded at least three-quarters of their daily food diary entries. Average macronutrient levels (70% fat, 18% protein, 5% net carbohydrate) and beta-hydroxybutyrate levels (p < 0.005) confirmed nutritional ketosis was maintained. Clinical improvements were found in total UPDRS, UPDRS Part III, miniBEST, Freezing of Gait, and quality of life. All participants lost weight; 58% reported no change in constipation and 8% reported improvement.ConclusionThis exploratory study deemed the modified ketogenic diet feasible and acceptable. Findings suggest a low dairy KD may provide similar benefits to a traditional KD for those with PD, while reducing potential risks associated with consuming higher amounts of animal dairy products.