Increase Your Vitamin D?

Due to research indicating the protective effects that vitamin D may have against conditions such as diabetes, heart disease and cancer, there have recently been requests in the scientific and public communities to raise the recommended levels of vitamin D.* At the end of 2008, both the US and Canadian governments announced they would be reviewing vitamin D and calcium, which may lead to higher recommended daily intakes.

A new study, out of the University of Maine, reports that maintaining adequate levels of vitamin D during winter months may require a daily dose four times the current recommended dose. Current recommended daily intakes (RDIs) of vitamin D are 200 IU for people up to 50 years of age, 400 IU for people between 51 and 70, and 600 IU for over the 70s years. In the study, published in the Journal of Nutrition, lead researcher, Susan Sullivan and her coworkers, recruited 112 women with an average age of 22.2. The women were assigned to receive a placebo from March 2005 until September 2005, and then randomly assigned to receive either placebo or a daily vitamin D3 supplement of 1,000 IU until February 2006.

Researchers found that, among the women who completed the study, those receiving the daily vitamin D supplements, 80% experienced optimal vitamin D concentrations. While our bodies do manufacture vitamin D on exposure to sunshine, the levels in some northern areas are so weak during the winter months that our body makes little or no vitamin D at all, meaning that dietary supplements and fortified foods are seen by many as the best way to boost intakes of vitamin D.

Vitamin D can be found in Viteyes Multivitamin AREDS Companion and Viteyes Complete.

*M.L. Nelson, J.M. Blum, B.W. Hollis, C. Rosen, S.S. Sullivan. Journal of Nutrition. “Supplements of 20 ug/d Cholecalciferol Optimized Serum 25-Hydroxyvitamin D Concentrations in 80% of Premenopausal Women in Winter.” 2009, Volume 139, Pages 540-546, doi:10.3945/jn.108.096180.