Memory, thinking skills in MS may be aided with Mediterranean diet
Risk of cognitive impairments 20% lower among patients in study
Following a Mediterranean diet may reduce the risk of cognitive problems, including with memory and thinking skills, in people with multiple sclerosis (MS), a preliminary study suggests.
The diet includes a high intake of fish, fruits, legumes, vegetables, and healthy fats (olive oil); and a low intake of meat, dairy products, and unhealthy saturated fats.
The study results will be presented at the American Academy of Neurology’s 75th Annual Meeting, in person in Boston and live online, April 22-27.
“It’s exciting to see that we may be able to help people living with MS maintain better cognition by eating a Mediterranean diet,” Ilana Katz Sand, MD, of the Icahn School of Medicine at Mount Sinai in New York and author of the study, said in a press release.
MS is a neurological disorder that occurs when the immune system mistakenly attacks the myelin sheath, a fatty protective coating around nerve fibers. This sheath normally protects nerve fibers from damage and helps send electric signals efficiently.
The loss of myelin leads to the progressive degeneration of nerve fibers and to MS symptoms, including fatigue, walking difficulties, loss of balance, pain, and slowed thinking.
“Cognitive difficulties are very common in MS, and they often get worse over time, even with treatment with disease-modifying therapies. People living with MS are very interested in ways they can be proactive from a lifestyle perspective to help improve their outcomes,“ said Katz Sand, who’s also a member of the American Academy of Neurology.
Effect of Mediterranean diet on cognition, memory
The study evaluated with a questionnaire how closely the diet of 563 people with MS was to the Mediterranean diet. Each patient’s diet was scored 0 to 14, with a higher score representing a closer adherence to the Mediterranean diet.
Participants were then divided according to their diet scores into four groups. The lowest group scored zero to four; the highest, nine or higher.
Memory and thinking skills were evaluated based on three tests, and a patient was considered to have cognitive impairment with a score below the fifth percentile on two of the tests.
A total of 108 patients (19%) showed cognitive impairment, with patients who more closely followed the Mediterranean diet having a risk of cognitive impairment 20% lower than those who didn’t follow it.
Specifically, 34% of the patients with a diet more unlike the Mediterranean diet had cognitive impairment (43 of 133 with the lowest score) compared to 13% among those whose diet was closer to the Mediterranean diet (13 of 103 in the highest score group).
The relationship between cognitive impairment and diet was found to be stronger among those with progressive MS, in whom the disease typically worsens steadily over time, compared to those with relapsing-remitting MS, which is characterized by periods of disease worsening followed by periods of remission.
According to Katz Sand, the results were identical when adjusted for factors that could impact cognitive functions, particularly socioeconomic status, body mass index (a measure of body fat), smoking habits, high blood pressure, and physical exercise.
“Among health-related factors, the level of dietary alignment with the Mediterranean pattern was by far the strongest predictor of people’s cognitive scores and whether they met the study criteria for cognitive impairment,” Katz Sand said.
Longer studies that follow MS patients over time and interventional clinical trials should be conducted to confirm these results, she said. Another limitation is that the cognitive tests were performed only once.
The study was supported by the Irma T. Hirschl/Monique Weill-Caulier Trust, the National Multiple Sclerosis Society, and the National Institutes of Health.