There is no debate about the many benefits of vitamin D. The “sunshine vitamin” supports the musculoskeletal system by governing calcium for optimal bone strength and density, in addition to enhancing muscle tone. Vitamin D also supports a robust immune response, reduced levels of inflammatory cytokines in the blood stream and reduced risk of heart attack. Vitamin D has even been shown to support the production of serotonin affecting mood. But what is the optimum level of intake of vitamin D.
Currently the Institute of Medicine recommends 600 IU per day up to age 70 and 800 IU if you are over 70. But recent research at the University of Edmonton indicates this is wrong due to a misinterpretation of the original IOM research. The IOM had made an error in defining the intake needed to reach and maintain a vitamin D level of 20 nanograms per milliliter in the blood stream. This is the minimum adequate amount the IOM calculates to be necessary for health. However most laboratories use 30 ng/ml as the minimum adequate level.
The current research shows that nearly half the people who get 600 IU of vitamin D a day do not reach the 20ng/ml level, and thus are deficient. The Edmonton investigators, using the same studies as the IOM, determined that a much greater intake of up to 7000 IU per day is necessary to reach and maintain an adequate blood level.
What does all of this amount to? First, find out your current level of vitamin D. This is shown routinely on a standard blood test. Then talk to your doctor about the optimum intake for you. This may vary for your general level of sun exposure, level of stress and physical activity, and time of year such as winter when sun intensity is weakest.
Creighton University. Recommendation for vitamin D intake was miscalculated, is far too low, experts say. Science Daily. Published March 2015.
VeugelersPJ, Ekwaru JP. A statistical Error on the Estimation of the Recommended dietary Allowance for Vitamin D. Nutrients 2014;6(10):4472-4475.