Healthy eating index and risk of multiple sclerosis: a case-control study

Background and Objective: Diet quality indices a provide unique approach to studying relations between diet and disease. Our objective was to investigate the relationship between Healthy Eating Index (HEI) and risk of multiple sclerosis (MS). Methods: We recruited 68 subjects with MS and 140 healthy subjects in a case-control study. Dietary intake was collected using a valid and reliable food frequency questionnaire. The HEI was calculated. Logistic regression was used to evaluate the relationship between HEI score and MS, after adjustment for season of the birth, daily stress, total energy intake, and age. Results: In comparison to controls, cases had lower mean scores for total HEI (68.4 vs 72.5, p  =  0.04), vegetable (7.5 vs 8.8, p  =  0.006), fruit (6.3 vs 8.0, p = 0.02), and food variety (8.0 vs 10, p = 0.008). When comparing the highest and the lowest quintiles of HEI, we observed a significant decreasing trend in the risk of MS (p for trend = 0.04). Although insignificant (p > 0.05), MS risk was reduced when comparing each quintile to the reference quintile (Q2: OR = 0.95, 95% CI: 0.37-2.38; Q3; OR = 0.62, 95% CI: 0.24-1.62; Q4: OR = 0.36, 95% CI: 0.12-1.14; and Q5: OR = 0.38, 95% CI: 0.13-1.19). Conclusions: Our study suggests that a high-quality diet assessed by HEI may decrease the risk of MS.