Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Multiple Sclerosis Health Center

Font Size

Vitamin D May Prevent MS

Dosage Found in Multivitamins Reduces Risk by 40%
WebMD Health News

Jan. 12, 2004 -- Evidence continues to mount showing that a little vitamin D can do a lot of good. The latest: A new study indicating that women who get doses typically found in daily multivitamin supplements -- of at least 400 international units -- are 40% less likely to develop multiple sclerosis compared with those not taking over-the-counter supplements.

This finding, by a team of Harvard researchers and published in this week's issue of Neurology, comes just a few days after another study links vitamin D deficiency with an increased risk of rheumatoid arthritis. Like MS, rheumatoid arthritis is an autoimmune disorder, a classification for some 80 different ailments in which the immune system mistakenly attacks healthy tissue and organs in the body.

"We've known for some time that vitamin D can affect function of the immune system, which could explain why it seems beneficial to both of these autoimmune conditions," says Kassandra Munger, MSc, of Harvard School of Public Health, a researcher for this study. "In animal studies, vitamin D been shown to suppress the autoimmune response in rats with a disorder very similar to MS."

Other recent studies link vitamin D deficiency to a greater risk of other ailments, including heart disease, diabetes, unexplained muscle and joint pain, and various forms of cancer. As with MS and other autoimmune diseases, the secret may be in how this nutrient affects cell activity.

"We need adequate amounts of vitamin D to keep cell growth and activity in check," says Michael Holick, MD, PhD, director of the Vitamin D Research Lab at Boston University Medical Center and considered by many to be the nation's leading authority on this vitamin. When the body is deficient in this crucial nutrient -- best known for coming from sunlight -- cells can go haywire, become overly active or multiplying too quickly.

That's why the new finding doesn't surprise Holick, who wasn't involved in it. "It's been well-known that if you live at a higher latitude, where there's less sun exposure, you're at a higher risk of developing MS," he tells WebMD. Conversely, if you live in a sunny climate where vitamin D can easily be absorbed year-round from sunlight for your first 10 years, "it imprints on you a decreased MS risk that can last a lifetime," Holick explains.

1 | 2 | 3

Today on WebMD

nerve damage
Learn how this disease affects the nervous system.
woman applying lotion
Ideas on how to boost your mood and self-esteem.
woman pondering
Get personalized treatment options.
man with hand over eye
Be on the lookout for these symptoms.
brain scan
worried woman
neural fiber
white blood cells
sunlight in hands
marijuana plant
muscle spasm