Timing of use of cod liver oil, a vitamin D source, and multiple sclerosis risk: The EnvIMS study

Mult Scler. 2015 Dec;21(14):1856-64. doi: 10.1177/1352458515578770. Epub 2015 May 6.


Background: Low vitamin D levels have been associated with an increased risk of multiple sclerosis (MS), although it remains unknown whether this relationship varies by age.

Objective: The objective of this paper is to investigate the association between vitamin D3 supplementation through cod liver oil at different postnatal ages and MS risk.

Methods: In the Norwegian component of the multinational case-control study Environmental Factors In Multiple Sclerosis (EnvIMS), a total of 953 MS patients with maximum disease duration of 10 years and 1717 controls reported their cod liver oil use from childhood to adulthood.

Results: Self-reported supplement use at ages 13-18 was associated with a reduced risk of MS (OR 0.67, 95% CI 0.52-0.86), whereas supplementation during childhood was not found to alter MS risk (OR 1.01, 95% CI 0.81-1.26), each compared to non-use during the respective period. An inverse association was found between MS risk and the dose of cod liver oil during adolescence, suggesting a dose-response relationship (p trend = 0.001) with the strongest effect for an estimated vitamin D3 intake of 600-800 IU/d (OR 0.46, 95% CI 0.31-0.70).

Conclusions: These findings not only support the hypothesis relating to low vitamin D as a risk factor for MS, but further point to adolescence as an important susceptibility period for adult-onset MS.

Keywords: Multiple sclerosis; age; cod liver oil; environmental risk factors; supplementation; susceptibility; timing; vitamin D.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Case-Control Studies
  • Cholecalciferol / therapeutic use*
  • Cod Liver Oil / therapeutic use*
  • Dietary Supplements*
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Male
  • Middle Aged
  • Multiple Sclerosis / epidemiology
  • Multiple Sclerosis / prevention & control*
  • Norway / epidemiology
  • Registries*
  • Risk
  • Young Adult


  • Cholecalciferol
  • Cod Liver Oil