Vitamin D affects hormone regulation in the body and appears to be connected to glucose and fat (lipid) metabolism. In addition to being associated with an increased risk of certain cancers, autoimmune diseases, and heart disease, low vitamin D levels have been associated with insulin resistance in some women with PCOS, prompting researchers from the Medical University of Graz, Austria, to investigate the effects of vitamin D supplementation in women with the condition.
The study consisted of 57 women with PCOS between the ages of 18 and 45. Participants were instructed to take 20,000 IU of vitamin D3 (cholecalciferol) each week for six months. Before supplementation began, and again after three and six months, vitamin D levels, and measures of glucose tolerance, insulin levels, reproductive hormone levels, blood lipids, and menstrual frequency were assessed.
At the study’s end, 46 had completed the treatment. At the start, 62% of them had insufficient vitamin D levels; by three and six months vitamin D levels had increased significantly. Glucose tolerance improved, and triglyceride and insulin levels dropped significantly. On the other hand, total and LDL (bad)-cholesterol levels increased, the significance of which isn’t certain.
Among women with menstrual irregularities at the beginning of the study, 30% experienced significant improvement after three months, and the number jumped to 50% after six months. One quarter of the women desiring pregnancy became pregnant during treatment with vitamin D.
“Vitamin D treatment might improve glucose metabolism and menstrual frequency in women with PCOS,” concluded lead study author, Dr. Elisabeth Wehr.
In addition to vitamin D, women living with PCOS might also improve their condition by following these tips:
(J Endocrinol Invest 2011;doi:10.3275/7748)