Higher fish consumption associated with slower MS disability progression

Higher fish consumption is associated with a reduced risk of disability progression in multiple sclerosis (MS), a Swedish nationwide population-based case-control study has found.

The Epidemiologic Investigation of Multiple Sclerosis (EIMS) study examined the influence of fish consumption habits on MS disease progression and the effect of changes in fish consumption after diagnosis on disability progression. [J Neurol Neuro Surg Psychiatry 2025;doi:10.1136/jnnp-2024-335200]

Newly diagnosed MS patients from hospital-based neurology units and private clinics across Sweden, recruited between April 2005 and June 2015, were categorized by fish consumption and followed for up to 15 years postdiagnosis through the Swedish MS registry. In 2021, a follow-up digital questionnaire capturing information on lifestyle habits from the time of diagnosis was used to assess participants (n=2,719) with complete information regarding fish consumption habits and Expanded Disability Status Scale (EDSS) outcomes. Of the 1,821 patients who completed the questionnaire (response rate, 67 percent), 1,719 were followed up further with EDSS in the Swedish MS registry.

Confirmed disability worsening (CDW) was defined as an increase in EDSS score by at least 1 point from baseline, sustained between two follow-up visits separated by no less than 6 months (1.5 points if EDSS at baseline was 0, 0.5 points if baseline EDSS was ≥5.5). Cox regression models, adjusted for clinical and demographic variables, were used to evaluate 24-week CDW, and progression to EDSS 3 and EDSS 4. Time to EDSS 3 and 4 were limited to subgroups of patients with a baseline EDSS <3.

Higher total consumption of lean and oily fish at diagnosis was associated with a reduced risk of CDW (hazard ratio [HR], 0.66; 95 percent confidence interval [Ci], 0.51–0.86), EDSS 3 (HR, 0.55; 95 percent CI, 0.39–0.79) and EDSS 4 (HR, 0.57; 95 percent CI, 0.33–0.96) compared with low consumption. These associations showed significant trends and remained consistent after further adjustment for various lifestyle factors.

“Our findings align with cross-sectional surveys indicating that higher fish consumption is linked to more favourable disability outcomes in MS,” wrote the authors.

Those who increased their fish consumption from a frequency score of 2–3 to a score of 5–6 within 5 years postdiagnosis (n=133) had a significantly reduced risk of CDW (HR 0.80, 95 percent CI, 0.63–0.99, compared with those who continued to have low fish consumption (n=400). There was a moderate correlation between consumption of lean and oily fish and reduced risk of CDW (correlation coefficient, 0.4; p<0.0001). Those with higher intakes of both types of fish experienced the most significant reduction in the risk of CDW.

Fish is a rich source of omega-3 fatty acids and taurine, which might benefit MS patients. Omega-3 fatty acids are well-known for their anti-inflammatory properties and have been associated with reduced MS-associated inflammation. Taurine, the most abundant free amino acid in the brain, exert cytoprotective actions through antioxidative and anti-inflammatory effects, and exogenous supply is necessary to meet physiological needs. Fish consumption also likely results in favourable modifications of gut microbiota composition and function, which have been shown to influence the production and metabolism of fatty acids, with potential immunomodulatory effects. [Nutr Neurosci 2021;24:569-579; Redox Biol 2019;24:101223; Int J Mol Sci 2019;20:3109]