People interested in improving their health often ask, “How much vitamin D should I take?” A common response is “Get your blood tested, and supplement according to the results.” The suggestion is logical. However, many folks do not know that the global medical community has yet to agree to standardization of vitamin D testing. In other words, test results can vary from laboratory to laboratory due to different testing equipment and protocols. Furthermore, the optimal reference range for vitamin D levels continues to be a subject of debate. As a passionate vitamin D advocate, I attended the 2013 Vitamin D […]