March 7, 2009
Another article has been published which indicates a need to revise our recommended daily allowance for vitamin D needs to be increased.
Maintaining adequate levels of vitamin D during winter months requires a daily dose that is four times the current recommended dose, says a new study.
Source: Journal of Nutrition
2009, Volume 139, Pages 540-546, doi:10.3945/jn.108.096180
"Supplements of 20 ug/d Cholecalciferol Optimized Serum 25-Hydroxyvitamin D Concentrations in 80% of Premenopausal Women in Winter”
Authors: M.L. Nelson, J.M. Blum, B.W. Hollis, C. Rosen, S.S. Sullivan
The study, led by Susan Sullivan from the University of Maine, has important implications for ongoing consultations on vitamin D recommendations, with the current level of five milligrams (200 International Units) seen by many as insufficient.
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.
Sullivan and her co-workers recruited 112 women with an average age of 22.2 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 (20 micrograms) until February 2006.
“Daily supplementation with 20 micrograms (about 2000 IU)of D3 during winter achieved optimal 25(OH)D concentrations (at least 75 nmol/L) in 80 per cent of participants, indicating that this dose is adequate to optimize vitamin D status in most young women in Maine,” concluded the researchers.
Bottom line - if you have an autoimmune disease get your vitamin D levels checked and take enough vitamin D or sunshine to get your vitamin D level in the upper range of normal.