Vitamin D and Skin Cancer Prevention

Craig Kraffert, MD

The relationship between Vitamin D and skin cancer is multi-faceted. The reasons are numerous but focus on two conflicting considerations. Traditionally, healthy levels of Vitamin D have been considered to be partially dependent on sun exposure. Yet the amount of sun exposure required for internal production of enough Vitamin D to ensure optimal health increases sun damage and the cumulative risk of skin cancer -- the conflict is a bit like a risk and benefit tango.

Studies Show Decreased Skin Cancer Risk

Recent research suggests that optimal internal Vitamin D levels may decrease the risk not only of skin cancer but of internal cancer as well. When it comes to Vitamin D, there are two key principles for optimizing overall health while minimizing UV induced skin aging and skin cancer risk. The best strategy for maintaining healthy Vitamin D levels consists of minimizing unprotected sun exposure while incorporating a generous oral supplementation of Vitamin D into the daily diet.

Recent data on the relationship between skin cancer and Vitamin D levels suggests that optimal levels of Vitamin D may decrease risk of basal cell carcinoma, squamous cell carcinoma and melanoma. The conclusions regarding basal cell carcinoma are based upon Vitamin D's effect on key pathways of basal cell carcinoma development as well as laboratory studies in mice and a few conflicting but generally supportive population studies of humans. The data on Vitamin D decreasing risk of squamous cell carcinoma is based solely on mouse studies. For melanoma, the overall pool of human study data is extensive and more convincing. Specifically, oral Vitamin D intake and optimal Vitamin D levels both appear to correlate with decreased risk of developing new melanoma or experiencing spread of previously diagnosed melanoma.

Vitamin D for Bone Growth and Optimal Health

In addition to its effects on skin cancer risk, Vitamin D is crucial in the regulation of bone growth and maintenance, and also appears to play important roles in immune, inflammatory and cardiovascular systems. An emerging pool of human data suggests that Vitamin D decreases overall mortality by all causes, including cancer. Vitamin D also appears to be associated with increased survival of those undergoing cancer treatment.

Recommended Doses of Vitamin D

Vitamin D levels can be increased by either sun exposure or oral intake. Oral intake is particularly important for those who avoid sun exposure, are darker skinned, live in higher latitudes or are older. Because the amount of sun required to generate consistently healthy Vitamin D levels is always associated with skin aging and increased skin cancer risk, oral Vitamin D supplementation is preferred. For most individuals, 600 IU per day is considered adequate. For individuals at increased risk of Vitamin D deficiency (which can be detected via a simple blood test), doses of 800 IU or more may be required. Daily doses of up to 4000 IU per day are safe but generally not necessary. Some doctors now advocate a daily dose of 2000 IU Vitamin D per day for those at risk of Vitamin D deficiency.

Today the Vitamin D jury is, for the most part, in. Sufficiently high Vitamin D levels are essential for optimal health. Consistently high sun exposure is one way to achieve Vitamin D optimization but is associated with premature skin aging and increased skin cancer risk so is not recommended. The Vitamin D pathway to better health is clear: supplement daily with oral Vitamin D - consider 2000 IU - and minimize unprotected sun exposure ... and enjoy the dance.