Vitamin D May Reduce Risk of Uterine Fibroids
Fibroids, also known as uterine leiomyomata, are noncancerous tumors of the uterus. Fibroids often result in pain and bleeding in premenopausal women, and are the leading cause of hysterectomy in the United States.
The body can make vitamin D when the skin is exposed to the sun, or vitamin D can come from food and supplements.
According to an article published in Epidemiology (2013;24:447-453), women who had sufficient amounts of vitamin D were 32% less likely to develop fibroids than women with insufficient vitamin D. The study included 1,036 women, aged 35-49, living in the Washington, D.C., area from 1996 to 1999. Study subjects were screened for fibroids using ultrasound and blood samples used to measure the primary circulating form of vitamin D, known as 25-hydroxy D. Those subjects with more than 20 ng/mL of 25-hydroxy D were categorized as sufficient, though some experts think even higher levels may be required for good health. Study participants also completed a questionnaire on sun exposure. Those who reported spending more than one hour outside per day also had a decreased risk of fibroids. The estimated reduction was 40%. Although fewer black than white participants had sufficient 25-hydroxy D levels, the estimated reduction in prevalence of fibroids was about the same for both ethnic groups.