Many people look to complementary and alternative therapies to treat symptoms of multiple sclerosis (MS). Among them, dietary supplements, including high-dose vitamins, are used most frequently. But will taking more than the recommended daily allowance of certain vitamins help your MS?

The question of whether larger doses of vitamins are beneficial is controversial. To be most effective, vitamins need to work in careful balance. A high concentration of one vitamin might cause a relative deficiency of another.

Vitamin D may be an exception. So far, vitamin D is one of the most intensely studied supplements for MS. For several years, there has been a growing interest in the role of low vitamin D levels and an increased risk of MS attacks or exacerbations.

Current research suggests a possible relationship between the two, although more-thorough studies are needed to establish a definite link. The connection between vitamin D and MS is supported by the association with exposure to sunlight and the risk of MS. There is a higher incidence and risk of MS in countries away from the equator.

The Recommended Dietary Allowance (RDA) for adults is 600 international units (IUs) of vitamin D a day. That amount increases to 800 IUs a day for those older than age 70. But be cautious with doses above 4,000 IUs a day. Doses greater than 4,000 IUs a day may sometimes be necessary in people who are vitamin D deficient, but large doses may also carry increased risks. A suggested maintenance dose to consider in patients with MS is 2,000 to 5,000 IUs daily.

Fruits and vegetables contain vitamins and other nutrients in useful proportions, working together to play their roles in good nutrition and disease prevention. For most people, even those with MS, the most reasonable course of action is receiving the recommended amount of vitamins from dietary sources, such as fruits and vegetables, rather than vitamin supplements.

If you have MS and are considering vitamin supplements, talk with your doctor first to determine what vitamins and doses he or she recommends. More research is needed, but high doses of vitamin D seem most helpful to people with naturally low blood levels. Your doctor may recommend a blood test to determine your baseline vitamin D level, and follow-up tests to determine when your level becomes normal if a supplement is recommended.