Mediterranean Diet and Associations with the Gut Microbiota and Pediatric-Onset Multiple Sclerosis: a Trivariate Analysis

Abstract The interplay between diet and the gut microbiota in multiple sclerosis (MS) is poorly understood. We conducted a case-control study to assess an interrelationship between diet, the gut microbiota, and MS by including 95 participants (44 pediatric-onset MS cases, 51 unaffected controls) enrolled from the Canadian Pediatric Demyelinating Disease Network study. All had completed a food-frequency questionnaire ≤ 21-years of age, and 59 also provided a stool sample. A 1-point increase in a Mediterranean diet score was associated with 37% reduced MS odds (95%CI: 10–53%). Higher fiber and iron intakes were also associated with reduced MS odds. Diet, not MS, explained inter-individual gut microbiota variation. Several gut microbes abundances were associated with both the Mediterranean diet score and MS presence, and these microbes were potential mediators of the protective associations of a healthier diet. Findings suggest that the potential interaction between diet and the gut microbiota is relevant in MS.