Often, after recommending that patients protect themselves from the sun, I am asked, “Shouldn’t I get sun exposure to get Vitamin D?”
It’s true that there has been concern that sunscreen use prevents the synthesis of vitamin D by the skin. Vitamin D is an essential nutrient that is vital for strong bones and a healthy immune system. Without vitamin D, the body cannot process calcium and phosphorus – two minerals necessary for healthy bones. The American Academy of Dermatology does not advocate getting vitamin D from sun exposure (natural) or indoor tanning (artificial) because ultraviolet (UV) radiation from the sun and tanning beds can lead to the development of skin cancer. The academy recommends that an adequate amount of vitamin D should be safely obtained from a healthy diet that includes foods naturally rich in vitamin D (e.g., dairy products and fish), foods/beverages fortified with vitamin D (e.g., fortified milk and fortified cereals), and/or vitamin D supplements – and not from UV exposure. The academy’s conclusions are based on the published review of the increasing body of scientific literature on this vitamin conducted by the National Academy of Sciences Institute of Medicine.
Unprotected UV exposure to the sun or indoor tanning devices is a known risk factor for the development of skin cancer. Since sun exposure is responsible for vitamin D production in the skin, wearing sunscreen can decrease the skin’s production of vitamin D, but alternative and safer options are available to obtain your vitamin D. Individuals who properly and consistently wear sunscreen or use other UV protective measures, and are concerned about their vitamin D levels, should discuss obtaining sufficient vitamin D from foods and/or vitamin supplements with their doctor. It is a well-established fact that UV radiation from sun or indoor tanning can cause cancer and numerous studies have demonstrated that exposure to UV radiation causes DNA damage in skin cells that can lead to skin cancer (melanoma and non-melanoma). More than four million new cases of skin cancer will be diagnosed in the United States this year. At current rates, one in five Americans will develop skin cancer in his or her lifetime. Approximately 75 percent of skin cancer deaths are from melanoma, and the incidence of melanoma has been rising at an alarming rate for at least 30 years.
Skin cancer is the most common cancer in the United States. While the benefits of vitamin D to bone health are well known, it also is well known that overexposure to UV radiation can cause skin cancer. UV rays can cause premature aging of the skin and skin cancer. There is significant scientific evidence to support this fact, which is why the World Health Organization’s International Agency of Research on Cancer classifies UV radiation from the sun and tanning devices as a known carcinogen (cancer-causing agent). UV exposure also can lead to cataracts and suppressed immune responses.
Dietary sources of vitamin D do not prematurely age the skin or increase the risk of developing skin cancer. Dietary sources (foods naturally rich in vitamin D, fortified foods and beverages) and vitamin supplements are available year-round and can easily be incorporated into a healthy lifestyle. Good sources include fortified milk, cheeses and yogurt, fortified cereal, and oily fish like salmon and tuna. Research shows that vitamin D supplements are well tolerated, safe and effective when taken as directed by a physician. As noted above, people need vitamin D to absorb calcium and phosphorus, which are essential for bone health. Vitamin D increases the efficiency of the body’s absorption of calcium 30 to 40 percent, and phosphorus by 80 percent. Fortified foods and beverages are rich in both vitamin D and calcium and maintain phosphate levels. Many dietary supplements also contain both of these minerals. Getting enough calcium and vitamin D is essential to prevent osteoporosis in men and women who are 50 years of age and older. Vitamin D from food and dietary supplements offers the same benefits – without the danger of skin cancer – as vitamin D obtained from UV light. Vitamin D cannot be used by the body until it is processed by the liver and the kidneys. The usable form of vitamin D created by this process is the same, regardless of how it enters the body.
To avoid vitamin D deficiency, a healthy diet and dietary supplementation are safe and effective means to obtain vitamin D. Since everyone is at risk for skin cancer, the academy recommends that people reduce their risk by seeking shade, covering up and wearing broad-spectrum, water-resistant sunscreen of SPF 30 or higher, regardless of their skin type, especially at high elevations in Arizona. In summary, an adequate amount of vitamin D should be obtained from a healthy diet that includes foods naturally rich in vitamin D, foods/beverages fortified with vitamin D and/or vitamin D supplements. Vitamin D should not be obtained from unprotected exposure to ultraviolet (UV) radiation. FBN
Northern Arizona Dermatology Center has been serving the region for 45 years. Please call 928-774-5074 to schedule your general skin exam with one of our eight board certified dermatologists, or visit us at www.nazderm.com.
By Scott M Dale, M.D., FAAD
Scott M Dale, M.D., FAAD received his doctorate from the University of Chicago Pritzker School of Medicine. Dr Dale sees patients at the Flagstaff location.