Review published in Advances in Nutrition finds the diet may benefit many patients with multiple sclerosis, particularly younger patients.

Multiple sclerosis affects some 2.3 million people worldwide.  Currently, there is no cure.  Many patients with multiple sclerosis have attempted various dietary modifications to gain better control over their disease; however, to date, there is not enough evidence to recommend a specific diet for these patients.

The ketogenic diet is a high-fat, low-carbohydrate diet that has traditionally been used to treat hard-to-control epilepsy among children.  More recently, the ketogenic diet, which exerts anti-inflammatory and neuroprotective effects, has been considered potentially beneficial for other neurological conditions, including multiple sclerosis.  Despite the diet’s potential therapeutic effects, researchers are concerned that it may also produce adverse side effects, including chronic low-grade metabolic acidosis, which can lead to kidney stones, lower bone mineral density, and loss of muscle mass.  Moreover, chronic low-grade metabolic acidosis can increase the risk of chronic diseases such as type 2 diabetes and hypertension.

Published in Advances in Nutrition, the international review journal of the American Society for Nutrition, Role of Ketogenic Diets in Multiple Sclerosis and Related Animal Models: An Updated Review, examines the latest research findings in an effort to determine whether and how strongly the evidence supports the adoption of a ketogenic diet among patients with multiple sclerosis.  Moreover, the authors of this scientific review sought to determine future research directions to address unresolved questions.

In order to conduct their research, the authors performed a thorough search of the scientific literature, including both human and animal model studies.  Their efforts led them to three pilot clinical trials of ketogenic diet therapy for multiple sclerosis, as well as several related studies.

According to the authors, “the preliminary findings suggest that the ketogenic diet is safe, feasible, and potentially neuroprotective and disease-modifying for patients with multiple sclerosis.”  In particular, the authors noted that studies reported improved Expanded Disability Status Scale (EDSS) scores, a standardized method of quantifying disability among patients with multiple sclerosis.  Patients also experienced other beneficial effects, including less fatigue and depression.

Two of the clinical trials the authors reviewed did report adverse events: the most common were respiratory tract infections; gastrointestinal symptoms such as diarrhea, constipation, and nausea; and genitourinary problems such as ureteric colic, urinary tract infection, and menstrual irregularities.  Overall, however, the authors found very few serious adverse events among multiple sclerosis patients consuming a ketogenic diet.

Not all multiple sclerosis patients appear to benefit equally from a ketogenic diet: “It appeared that younger patients with milder disease or the relapsing-remitting form of the disease benefited more from the ketogenic diet in terms of EDSS score, quality of life, and fatigue.”  The authors believe that “further studies are clearly needed to identify the patient characteristics that lead to more favorable responses to a ketogenic diet intervention.”

While initial study results are promising, the authors acknowledged that the research they reviewed shared some limitations.  The studies, for example, “are largely pilot and exploratory in nature.”  Moreover, “the sample size is likely insufficient for clarification of the ketogenic diet’s effects on many multiple sclerosis-related outcomes.”

The authors have called for more research.  In particular, they noted that “pediatric multiple sclerosis has been underrepresented in existing studies, thus further research is needed to assess the role of the ketogenic diet in this patient population.”