Multiple Sclerosis and Diet: the role of food components, dietary patterns and lifestyle

Nutrition is one of the environmental factors that can impact not only on multiple sclerosis (MS) pathogenesis, but also on its clinical course and progression. Over the years, the interest towards diet and MS increased, with several studies investigating the possible relationship between nutrients and/or bioactive compounds, dietary components, food groups, dietary patterns and MS. To date, no precise and universal recommendations have been proposed for MS, but currently available data suggest that the union of a balanced diet and an overall healthy lifestyle may determine an amelioration in several clinical parameters and in the quality of life for patients with MS (pwMS). The present project aimed at evaluating the possible impact of the dietary habits and general lifestyle on MS severity in a group of pwMS. More deeply, we investigated the relationship between MS severity and (i) ultra-processed foods (UPFs) consumption, (ii) adherence to Mediterranean diet (MedDiet), (iii) polyphenols, (iv) Dietary Inflammatory Score (DIS) and Lifestyle Inflammatory Score (LIS). A cross-sectional observational design was adopted. Demographic (age, sex, marital status, educational level), neurological (EDSS, MSSS), and nutritional (anthropometric measures, dietary habits) information were collected. Physical activity, smoking habits were also investigated. Eating habits were collected through a validated 110-items Food Frequency Questionnaire. Ultra-processed foods were identified according to the NOVA classification. Adherence to MedDiet was evaluated through the Medi-Lite score, (poly)phenols content was retrieved from the Phenol-Explorer database. DIS and LIS were calculated according to Byrd et al.,(2019). DIS is made up of 19 elements, comprehending 18 foods or foods groups (i.e. coffee and tea, leafy green vegetables), with the latter element comprehending single micronutrients supplements use. LIS is composed of: (i) body mass index (overweight/obesity), (ii) smoking habits (current/former smokers), (iii) physical activity (moderate/heavy) and (iv) alcohol consumption (moderate/high). Participants were divided into groups based on MS severity (“mild” and “moderate-to-high”), their level of intake of UPFs or (poly)phenols (low/high) or their level of adherence to MedDiet (low/medium/high). A total of 130 participants were enrolled in the project. Five of them decided not to complete the telephonic interview, 19 had missing data. The final sample was composed of 106 pwMS. Those with a higher UPF consumption had a 3-fold higher risk of moderate-to-high MS severity compared to lower consumption (OR = 2.97, 95% CI: 1.13–7.77). As well, higher adherence to MedDiet was associated with a 6.18 (95% CI: 1.44, 26.59) higher probability of having a mild-to-moderate MS. None of the single constituents of the Medi-Lite score was individually associated with MS severity. No statistically significant results were found when analyzing total (poly)phenols intake, neither total DIS and LIS score and MS. Hydroxycinnamic acids (HCAs) and vegetables were associated with a 6.5-fold (95% CI: 2.15, 19.92) and 4.5 times (95% CI 1.49, 14.28) higher odds of mild MS, respectively. Among DIS and LIS components, “leafy greens” (OR 1.67; 95% CI 1.50,18.74) “heavy physical activity” (OR 5.51; 95% CI 1.66, 18.30) and alcohol consumption (OR 5.61; 95% CI 1.19-26.47) were associated with mild MS. These results might be determined by several mechanisms (i.e. antioxidant and anti/proinflammatory properties of some elements, gut-microbiota axis). Some of our findings deepened for the first time some uninvestigated aspects of the relationship between diet and MS(i.e. the link with UPFs), while confirming the literature data about MedDiet and MS. DIS and LIS application in MS is still scarce, thus our data may serve as a starting point to further investigatethe impact of lifestyle, specifically alcohol consumption, on the disease onset and progression.