New research led by Dr. Helen Tremlett suggests the possibility—although does not prove—that eating a Mediterranean diet might lower the risk of developing pediatric-onset multiple sclerosis (MS), a disease where the immune system attacks the protective covering of nerve cells in the brain.
The Mediterranean diet, which consists of fruits, vegetables, whole grains and healthy fats, has been consistently associated with better health outcomes in the general population, including a reduced risk of mortality and a lower risk of developing chronic diseases and neurodegenerative conditions such as Parkinson and Alzheimer disease. Recent studies have also suggested that a Mediterranean diet may alleviate MS symptoms, such as fatigue, but whether the diet is associated with a reduced risk of MS is unclear.
In this new study, published in the journal Communications Medicine, Dr. Tremlett and her team investigated how diet and gut microbiota are linked to MS in young people.
“We examined the diet and types of bacteria in stool samples from those with and without MS,” says Dr. Tremlett, DMCBH member and professor of neurology in UBC’s Faculty of Medicine. “We found that a diet richer in fibre and Mediterranean foods were less common in those with MS. This dietary pattern was also linked to certain differences in the gut bacteria.”
This study showed that a higher Mediterranean diet score, in addition to consuming more fibre and iron, was associated with a reduced likelihood of having MS. For example, an increase of 1-point in the Mediterranean diet score was associated with 37% reduced odds of MS and a 1-gram increase in fibre was associated with 13% lower odds of MS.
“We also discovered that certain gut bacteria were more common in children with MS,” says Dr. Ali Mirza, the study’s lead author and recent PhD graduate from the Tremlett lab. “For example, a type of bacteria called Methanobrevibacter, which is linked to constipation, was more prevalent in MS patients. On the other hand, beneficial bacteria that help produce health-promoting short-chain fatty acids from fiber were less common.”
The results of this study suggest that the Mediterranean diet can positively impact gut bacteria. This aligns with other studies showing that a diet rich in fibre and healthy nutrients can support overall gut health.
To date, only two other published studies have investigated the connection between the Mediterranean diet and MS risk. Both studies looked at adults exclusively and neither included gut microbiota. Therefore, Dr. Tremlett and her team’s research is unique as it connects Mediterranean diet scores and fiber intake with specific gut bacteria linked to MS in children.
While further research is needed to fully understand these relationships, the study’s findings raise the possibility, but do not prove, that following a Mediterranean diet rich in fibre and iron might help lower the risk of pediatric-onset MS by promoting a healthy gut microbiome.
“While our study cannot prove that what we eat may prevent MS,” notes Dr. Tremlett. “Our findings do suggest that the interplay between the microbiota and diet may be of relevance in MS and is worthy of further research.”
