Is diet associated with physical capacity and fatigue in persons with multiple sclerosis? -Results from a pilot study

Diet may have immunomodulatory effects in persons with multiple sclerosis (PwMS) and studies suggest that diet may be considered a complementary treatment to control the progression of the disease. The role of nutrition in MS and related symptoms have been reported by several studies but remains controversial.

To explore the association between dietary intake and physical capacity and fatigue in PwMS.

An explorative cross-sectional pilot study was conducted, in which 23 ambulatory PwMS were enrolled. Dietary intake was assessed using a 4-day food record. Outcome variables included a 6-Minute Walk Test (6MWT), a VO_2max test, and self-reported questionnaires assessing fatigue severity (Fatigue Severity Scale, FSS) and impact (Modified Fatigue Impact Scale, MFIS). Associations between variables were determined using simple and multiple regression analyses.

In the simple but not the multiple (adjusted for sex and age) regression analyses the carbohydrate intake (% of total energy intake) was positively associated with physical capacity (i.e. the 6MWT and VO_2max test), whereas fat intake (% of total energy intake) was inversely associated with physical capacity. In the multiple regression analyses the absolute intake of ω-3 and vitamin D showed trends towards a positive association with the MFIS physical subscale and VO_2max, respectively.

Although not consistent across analyses, these findings suggest that better physical capacity most often is associated with a diet rich in carbohydrates and reduced fat content. Further research and randomized controlled trials are required to fully assess the role and the efficacy of diet quality and content on physical capacity in PwMS.