“The benefits of moderately increased exposure to sunlight – namely the production of vitamin D, which protects against the lethal effects of many forms of cancer and other diseases – may outweigh the risk of developing skin cancer in populations deficient in vitamin D.

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So, how can people get the benefits of vitamin D without running the risk of deadly skin cancer?

“As far as skin cancer goes, we need to be most worried about melanoma, a serious disease with significant mortality,” Setlow says.

Melanoma is triggered by UVA (the long UV wavelengths) and visible light. Vitamin-D production in the body, on the other hand, is triggered by UVB (the short UV wavelengths at the earth’s surface). “So perhaps we should redesign sunscreens so they don’t screen out as much UVB while still protecting us from the melanoma-inducing UVA and visible light,” Setlow says.

Increased UVB exposure may result in an increase in non-melanoma skin cancers. But these are relatively easy to cure and have very low mortality rates compared with the internal cancers vitamin D appears to protect against, Setlow adds.

Another option would be to increase vitamin D consumption while continuing to wear sunscreen. Vitamin D is easily accessible in many foods and liquids, such as cod liver oil and milk, and in dietary supplements.” (Science Daily)