Some studies have suggested that minerals such as zinc and iron may play a role in how multiple sclerosis progresses. But little was known about whether zinc, iron, and other minerals play a role in the development of the disease. A new study shows no link between dietary intake of several minerals and whether people later develop MS. These results have the potential to shape future research efforts and to save study participants from avoidable risks.

The study involved 80,920 female nurses in the Nurses’ Health Study and 94,511 in the Nurses’ Health Study II. Using a questionnaire, the women were asked about diet and any supplement use every four years for up to 20 years of follow-up before some of the women developed MS. 

The minerals studied were zinc, iron, potassium, magnesium, calcium, phosphorus, manganese, and copper. During the study, 479 of the women developed MS. 

The researchers evaluated the women’s intake of the minerals to see if higher intake was tied to a higher or lower risk of MS. No such relationship was found. Researchers looked at mineral intake at the beginning of the study and also cumulative intake before MS onset and found no link. 

The results were the same when researchers adjusted for other factors that could affect the risk of MS, such as smoking and taking vitamin D supplements.

The study is published in the journal Neurology.