Approximately 36 million people in the United States suffer from the unrelenting, debilitating pain of migraines, according to the Migraine Research Foundation. Despite it being one of the world's top 20 most disabling medical conditions, little is known about the underlying causes of migraines. Based on research published since 2008, low levels of vitamin D appear to play an important role in migraine development.
Vitamin D is an essential fat-soluble vitamin that is naturally produced by your body when ultraviolet light from the sun hits your skin. Vitamin D is a major contributor to overall good health, as low levels of this vitamin have been linked to heart disease, cancer, osteoporosis, chronic pain disorders and, most recently, to migraines. While experts disagree on exactly where to draw the line for vitamin D deficiency, the Vitamin D Council states the minimum acceptable level in the blood is 50 nanograms per milliliter or 125 nanomoles per liter because this is the point where your body starts to use vitamin D as soon as it is made or consumed, which isn't sustainable.
Two different studies presented at the American Headache Society's Annual Scientific Meeting in 2008 and 2010 showed that people who suffer from chronic migraines tend to have insufficient levels of vitamin D. In the 2008 study, 41.8 percent of migraine patients were vitamin D deficient, and those who had had suffered from migraines the longest were most likely to be deficient. These studies explain why more people suffer from migraine and tension-type headaches at higher latitudes -- farther away from the equator -- and why more headaches are reported in the autumn or winter than in the summer.
Mode of Action
Researchers have not uncovered how vitamin D is involved in the development of migraines, but there is speculation that it may be related to inflammatory pathways. During a migraine, the pain intensifies as the tissue surrounding the brain becomes inflamed. Since vitamin D is a known anti-inflammatory, low levels of this vitamin could promote inflammation or allow it to progress unchecked.
Results from four case studies have provided preliminary evidence that raising vitamin D levels may be an effective way to treat migraines. All four female patients experienced significant improvements in their migraine symptoms after treatment with calcium and vitamin D supplements. Investigations of vitamin D as a migraine treatment are still in their early stages, and more research, including large-scale clinical trials, is necessary before vitamin D supplements can be recommended as an effective treatment option.
Sources and Supplements
Most people need about 1,000 International units of vitamin D every day. While it is possible to get vitamin D from foods or supplements, the best source of vitamin D is the sun. In one day at the beach, a light-skinned person wearing a bathing suit can absorb 20,000 International units without getting sunburned. In comparison, taking your multivitamin with a glass of fortified milk or orange juice will only give you about 300 to 500 International units. It is important, however, to balance getting enough sunlight to top up your vitamin D levels with protecting your skin from damage.