Vitamin D in adult health and disease: a review and guideline statement from Osteoporosis Canada (summary).

CMAJ • SEPTEMBER 7, 2010 • 182(12) © 2010 Canadian Medical Association or its licensors 1315 The 2002 guidelines for the management of osteoporosis published by Osteoporosis Canada identified adequate vitamin D status, in addition to calcium from diet or supplements, as essential for the prevention of osteoporosis. Since then, our knowledge of the role of vitamin D (both D2 and D3) in fractures, falls and other health outcomes has expanded. Canadian recommendations for vitamin D, which are more than 10 years old, have never been supported by ad equately conducted dose-finding studies and were derived primarily from early nutritional science estimates of the minimal intake necessary to prevent extreme deficiency states. We reviewed advances in knowledge about vitamin D physiology and optimal intake requirements for adults (except in pregnancy and during lactation) to update the 2002 clinical practice guidelines. In reviewing trials of vitamin D, it is important to remember that, unlike the situation for trials of pharmacologic agents, any reported benefits of vitamin D supplementation reflect correction of a deficiency in the population under study.