Women with a history of migraine headaches have a reduced risk of developing breast cancer, according to a study that appeared in the November, 2008 issue of Cancer Epidemiology Biomarkers and Prevention.

Migraines are not simple headaches. Lasting 4 to 72 hours sufferer intense pain, they cause the sufferer nausea, vomiting, as well as heightened sensitivity to light and noise.

Throughout time, researchers connected an increased risk of breast cancer with many factors, such as alcohol intake, aspirin, diet, hormone replacement, non-steroidal anti-inflammatory drugs, as well as lack of physical activity. But now they came up with an amazing claim: migraine headaches cut breast cancer risk.

Dr. Li and colleagues claimed that migraines and breast cancer are both associated with estrogen. High levels of estrogen are linked to an increased risk of breast cancer, and women who experience migraines are believed to have low levels of the sex hormone. So these women have a lower risk of developing breast cancer. Researchers also note that women are two to three times more likely than men to experience migraines.

To reach this conclusion, researchers looked at 3,412 post-menopausal women. While 1,938 of them were diagnosed with breast cancer, the others had no history of the disease. "Overall, women who had a history of migraines had a 30 percent lower risk of breast cancer compared to women who did not have a history of such headaches," said Dr. Christopher Li, M.D., Ph.D., Fred Hutchinson Cancer Research Center in Seattle.