The study was the first randomized-controlled trial to examine the potential benefits of the low fat diet on the management of MS. The study found no significant differences between the two groups in brain lesions detected on MRI brain scans or on other measures of MS. But while the number of trial participants was relatively small, study leaders believe the significantly improved fatigue symptoms merited further and larger studies of the diet.
“Fatigue can be a debilitating problem for many people living with relapsing-remitting MS,” said Vijayshree Yadav, M.D., an associate professor of neurology in the OHSU School of Medicine and clinical medical director of the OHSU Multiple Sclerosis Center. “So this study’s results — showing some notable improvement in fatigue for people who follow this diet — are a hopeful hint of something that could help many people with MS.”
The study investigated the effects of following a diet called the McDougall Diet, devised by John McDougall, M.D. The diet is partly based on an MS-fighting diet developed in the 1940s and 1950s by the late Roy Swank, M.D., a former head of the division of neurology at OHSU. The McDougall diet, very low in saturated fat, focuses on eating starches, fruits and vegetables and does not include meat, fish or dairy products.
The study, which began in 2008, looked at the diet’s effect on the most common form of MS, called relapsing-remitting MS. About 85 percent of people with MS have relapsing-remitting MS, characterized by clearly defined attacks of worsening neurological function followed by recovery periods when symptoms improve partially or completely.
The study measured indicators of MS among a group of people who followed the McDougall Diet for 12 months and a control group that did not. The study measured a range of MS indicators and symptoms, including brain lesions on MRI brain scans of study participants, relapse rate, disabilities caused by the disease, body weight and cholesterol levels.
It found no difference between the diet group and the control group in the number of MS-caused brain lesions detected on the MRI scans. It also found no difference between the two groups in relapse rate or level of disability caused by the disease. People who followed the diet did lose significantly more weight than the control group and had significantly lower cholesterol levels. People who followed the diet also had higher scores on a questionnaire that measured their quality of life and overall mood.
The study’s sample size was relatively small. Fifty-three people completed the study, with 27 in the control group and 22 people in the diet group who complied with the diet’s restrictions.
“This study showed the low-fat diet might offer some promising help with the fatigue that often comes with MS,” said Dennis Bourdette, M.D., F.A.A.N., chair of OHSU’s Department of Neurology, director of OHSU’s MS Center and a study co-author. “But further study is needed, hopefully with a larger trial where we can more closely look at how the diet might help fatigue and possibly affect other symptoms of MS.”
The study was funded by the McDougall Research & Education Foundation, the OHSU Foundation and the U.S. Department of Veteran Affairs.
About the OHSU Brain Institute
The Oregon Health & Science University Brain Institute is a national neuroscience leader in patient care, research and education. With more than 1,000 brain scientists and specialists, OHSU is home to one of the largest communities of brain and central nervous system experts in the nation. OHSU Brain Institute scientists have won national recognition for breaking new ground in understanding Alzheimer’s disease and for discoveries that have led to new treatments for Parkinson’s disease, multiple sclerosis, stroke and other brain disorders and diseases.
Oregon Health & Science University is a nationally prominent research university and Oregon’s only public academic health center. It serves patients throughout the region with a Level 1 trauma center and nationally recognized Doernbecher Children’s Hospital. OHSU operates dental, medical, nursing and pharmacy schools that rank high both in research funding and in meeting the university’s social mission. OHSU’s Knight Cancer Institute helped pioneer personalized medicine through a discovery that identified how to shut down cells that enable cancer to grow without harming healthy ones. OHSU Brain Institute scientists are nationally recognized for discoveries that have led to a better understanding of Alzheimer’s disease and new treatments for Parkinson’s disease, multiple sclerosis and stroke. OHSU’s Casey Eye Institute is a global leader in ophthalmic imaging, and in clinical trials related to eye disease.