People with MS are often keen to find out what action they can take to affect the course of their disease and symptoms, with dietary changes being of particular interest.
Although several studies have investigated the link between diet and MS symptoms, many of these studies are small, focusing only on specific food groups or nutrients. In a recent US study published in the journal Neurology, researchers looked at the link between diet, disability, and symptom severity in people with MS.
The research surveyed 6,989 people with MS, registered with the large patient database: the North American Research Committee on MS (NARCOMS). In this survey, the researchers asked questions about each person’s current dietary intake, physical activity, smoking status, body mass index (BMI), and any other previous diet history.
The results showed that people with healthier diets (those high in fruits, vegetables, legumes, whole grains and low in added sugars and red or processed meats) had around a 20 per cent lower chance of experiencing high levels of disability and severe depression than those with the least healthy diets. Specifically, a higher intake of whole grains and dairy was linked to less disability, as were current or historical efforts to lose weight.
The survey results suggest that some diets, such as the gluten-free and Wahl’s diet, were associated with a higher level of disability. However, this could be a reflection of the fact that more people with progressive MS were on, or had tried, this diet.
Exposure to a weight loss diet was associated with lower disability, whilst exposure to other, more specific diets was not associated with a reduction or increase in disability. No link between diet and fatigue, pain or cognitive symptoms were found. However, a healthy lifestyle – such as being physically active, having a BMI of less than 25, and not smoking – was connected to a lower likelihood of severe depression, pain, fatigue, issues with cognition, as well as lower disability.
The researchers did not find any link between healthy or unhealthy diets and relapse rates or MS symptom severity. This study looked at people’s diet and lifestyle at a particular snapshot in time, rather than following them over time after a change in diet or lifestyle. Therefore, it is not possible to tell if the differences in disability and symptoms were due to lifestyle, or if the relationship is the other way around. It is possible that severe MS symptoms hinder a person’s ability to live a healthier lifestyle.
Further long-term studies are required to confirm and investigate these results. The USA National MS Society is also currently funding a clinical trial looking at the effects of the Wahls and Swank Diets on fatigue in people with MS.
It is not known if and how diets can cause changes to MS symptoms. Diet is known to affect gut microbiota and immune status, and further studies are needed to investigate the mechanisms by which diet is linked to disability and/or symptom severity.
With thanks to MS Research Australia – the lead provider of research summaries on our website.