Higher dietary nitrate intake is associated with lower likelihood of first clinical diagnosis of central nervous system demyelination in Australian women

Dietary nitrate is a precursor to nitric oxide, for which plausible mechanisms exist for both beneficial and detrimental influences in first clinical diagnosis of central nervous system demyelination (FCD), a common precursor to the diagnosis of multiple sclerosis (MS). Whether dietary nitrate has any role in FCD onset is unclear. We tested associations between nitrate intake from food sources (plant, vegetable, animal, processed meat, and unprocessed meat) and likelihood of FCD. We used data from the Ausimmune Study (264 cases, 474 controls) and logistic regression with full propensity score matching. In females, higher nitrate intake from plant-based foods (odds ratio [OR] per 60 mg/day = 0.50; 95 % confidence interval [CI] 0.31, 0.81; p = <0.01) and vegetables (OR per 60 mg/day = 0.39; 95 % CI 0.22, 0.70; p = <0.01), but not other sources, was statistically significantly associated with lower likelihood of FCD. In males, no associations were found between any source of nitrate intake and likelihood of FCD. Our results support further research to explore a possible beneficial role for plant-derived nitrate in people at higher risk of MS.