Related Experiment Video
Updated: Feb 24, 2026
Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
Published on: February 19, 2021
No association between dietary sodium intake and the risk of multiple sclerosis
Marianna Cortese1, Changzheng Yuan2, Tanuja Chitnis2
1From the Departments of Clinical Medicine and Global Public Health and Primary Care (M.C.), University of Bergen; The Norwegian Multiple Sclerosis Competence Center (M.C.), Haukeland University Hospital, Bergen, Norway; Departments of Nutrition (M.C., C.Y., A.A., K.L.M.) and Epidemiology (A.A.), Harvard T.H. Chan School of Public Health; Partners Multiple Sclerosis Center (T.C.), Brigham and Women's Hospital; and Channing Division of Network Medicine, Department of Medicine (A.A.), Brigham and Women's Hospital and Harvard Medical School, Boston, MA. Marianna.Cortese@uib.no.
Objective:
To prospectively investigate the association between dietary sodium intake and multiple sclerosis (MS) risk.
Methods:
In this cohort study, we assessed dietary sodium intake by a validated food frequency questionnaire administered every 4 years to 80,920 nurses in the Nurses' Health Study (NHS) (1984-2002) and to 94,511 in the Nurses' Health Study II (NHSII) (1991-2007), and calibrated it using data from a validation study. There were 479 new MS cases during follow-up. We used Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the effect of energy-adjusted dietary sodium on MS risk, adjusting also for age, latitude of residence at age 15, ancestry, body mass index at age 18, supplemental vitamin D intake, cigarette smoking, and total energy intake in each cohort. The results in both cohorts were pooled using fixed effects models.
Results:
Total dietary intake of sodium at baseline was not associated with MS risk (highest [medians: 3.2 g/d NHS; 3.5 g/d NHSII] vs lowest [medians: 2.5 g/d NHS; 2.8 g/d NHSII] quintile: HRpooled 0.98, 95% CI 0.74-1.30, p for trend = 0.75). Cumulative average sodium intake during follow-up was also not associated with MS risk (highest [medians: 3.3 g/d NHS; 3.4 g/d NHSII] vs lowest [medians: 2.7 g/d NHS; 2.8 g/d NHSII] quintile: HRpooled 1.02, 95% CI 0.76-1.37, p for trend = 0.76). Comparing more extreme sodium intake in deciles yielded similar results (p for trend = 0.95).
Conclusions:
Our findings suggest that higher dietary sodium intake does not increase the risk of developing MS.
