Updated January 31, 2012

There is strong evidence of the harms of exposure to UV radiation from the sun and other sources, including skin cancer, melanoma and some cataracts.

There is strong evidence of the benefits of adequate vitamin D status on musculoskeletal health and prevention of fractures in the elderly.

Vitamin D is obtained through skin exposure to UVB radiation, and also through diet (particularly fortified foods) and supplementation. To minimize the health risks associated with UVB radiation exposure while maximizing the potential benefits of optimum Vitamin D status, supplementation and small amounts of sun exposure - not sunbathing and not tanning salons - are the preferred methods of obtaining vitamin D.

Groups at risk of not obtaining adequate amounts of vitamin D include:

• the elderly;
• exclusively breast-fed babies;
• individuals with dark skin pigmentation;
• individuals with limited skin exposure to the sun (e.g. housebound, or those who wear clothing covering most of the skin for cultural/ religious reasons); and
• those who during the winter are living above 37 latitude (Canada and Northern U.S.).

If you are concerned about adequate vitamin D levels, discuss supplementation with your health care practitioner. For breast-fed babies, vitamin D drops are available on their own (only in Canada), or as part of a multi-vitamin drop, and are recommended as a supplementation source by health authorities both in Canada and the USA. For adults, current federal recommendations are 600 IU/day for age 9 to 70 and 800 IU for those over 70. The most appropriate supplementation level is likely to be above this but below the safe upper level of 4000 IU/day for adults. We think that the available evidence supports an adult dose of 1000 IU/day. More research is needed to determine the optimal amount of vitamin D supplementation required to prevent health problems.

In Canada, for more information about supplementation for breast fed babies you can go to Health Canada’s website.

Reference: North American Conference on UV, Vitamin D, and Health, Toronto, March 3, 2006