Eating more fish may slow progression of multiple sclerosis

Key takeaways:

• High intake of oily and lean fish reduced the risk for confirmed worsening disability in adults with MS.
• The results may be due to several nutrients found in fish, like taurine and omega-3 fatty acids.

Individuals diagnosed with multiple sclerosis who consumed high levels of fish had lower risk for worsening disease-related disability, results from a Sweden-based cohort study showed.

Findings from the longitudinal analysis published in the Journal of Neurology, Neurosurgery & Psychiatry revealed that although the greatest benefits appeared for individuals who consumed higher levels of fish at diagnosis, those who increased intake after still benefited from lower risk of disability associated with disease progression.

Both lean and oily fish were tied to such outcomes, “suggesting that nutrients beyond omega-3 fatty acids — such as taurine and other bioactive compounds — could be contributing to the observed benefits,” Anna Karin Hedström, a senior research specialist at the Karolinska Institute in Sweden, told Healio.

According to Hedström and colleagues, preventing MS disease progression “remains a major challenge” despite recent advances.

“Understanding the impact of environmental exposures and lifestyle habits on disease progression is increasingly important for optimizing patient outcomes,” they wrote.

In the analysis, the researchers examined a sample of 2,719 adults from the Epidemiological Investigation of MS study, assessing data on fish intake and Expanded Disability Status Scale (EDSS) outcomes.

Such outcomes included confirmed worsening disability, defined as an increase in the EDSS score by at least 1 point from baseline, and progression to EDSS 3 and EDSS 4.

Meanwhile, researchers ranked oily and lean fish intake on a scale between 2 (the lowest exposure) and 6 (the highest exposure) based on participants’ responses.

The initial study cohort included participants followed for 15 years, of whom 1,719 completed a follow-up questionnaire in 2021.

Compared with lower consumption of lean and oily fish, higher consumption corresponded with a reduced risk for:

• confirmed disability worsening (HR = 0.66; 95% CI, 0.51-0.86);
• EDSS 3 (HR = 0.55; 95% CI, 0.39-0.79); and
• EDSS 4 (HR = 0.57; 95% CI, 0.33-0.96).

The 133 participants who responded to the follow-up questionnaire and increased their baseline score from 2-3 to 5-6 within 5 years after their MS diagnosis had a 20% lower risk (HR = 0.8; 95% CI, 0.63-0.99) for confirmed disability worsening compared with those who continued to eat little or no fish.

Meanwhile, the 16 participants who raised their baseline score of 2 to a score of 5-6 had a 59% lower risk (HR = 0.41; 95% CI 0.17-0.95) of confirmed disability worsening.

These results remained consistent even after the researchers adjusted for several lifestyle factors like alcohol intake, BMI, smoking status, physical activity and sun exposure.

The analysis could not determine causality but “it adds to the growing body of evidence supporting the potential role of diet in MS management,” Hedström explained.

“For primary care providers and neurologists, the key takeaway is that fish consumption appears to be a modifiable factor associated with better long-term outcomes in MS,” she told Healio. “Encouraging patients to include fish in their diet — particularly as part of an overall healthy and anti-inflammatory eating pattern — may be a simple and practical approach to support MS management.”

Hedström added that the results also indicate “that that it is never too late to adopt beneficial dietary habits.”