An overview of the current state of evidence for the role of specific diets in multiple sclerosis

Background: Surveys of people with multiple sclerosis (MS) report that most are interested in using dietary modifications to potentially reduce the severity and symptoms of their disease. This review provides an updated overview of the current state of evidence for the role of specific diets in MS and its animal models, with an emphasis on recent studies including efficacy and safety issues related to dietary manipulations in people with MS. Methods: Studies were identified using a PubMed search for each diet in both MS and experimental autoimmune encephalomyelitis, by review of the reference list of papers identified in the search process, and by searching clinicaltrials.gov for ongoing studies. Each study was evaluated and the data was summarized. Each diet was assigned a level of evidence for its use in MS based on the Quality Rating Scheme for Studies and Other Evidence. Results: Several diets have been explored in people with MS and animal models of MS. Most human trials have been small and non-blinded, limiting their generalizability. Many have also been of short-duration, potentially limiting their ability to find clinically meaningful changes. Presently, insufficient evidence exists to recommend the routine use of any specific diet by people with MS. Clinical trials are ongoing or planned for many diets including the Swank Diet, Wahl's diet, McDougall diet, Mediterranean diet, and intermittent fasting. Results of these studies may help guide clinical recommendations. Conclusion: There is insufficient evidence to recommend the routine use of any specific diet by people with MS. Some diets touted for MS may have potential negative health consequences. It is important that clinicians inquire regarding dietary manipulations, so they can educate patients on any known efficacy data and potential adverse effects of individual diets. Consultation with a registered dietician is recommended for patients undertaking restrictive diets.