Sun exposure: Can it help fight cancer?

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Sun exposure: Can it help fight cancer?


I thought sun exposure increased the risk of cancer. But I just read that sunlight may help fight cancer. Is this true?



While the ultraviolet radiation in sunlight increases the risk of skin cancer, it also stimulates the production of vitamin D. According to the National Cancer Institute (NCI), some researchers are now investigating whether vitamin D may have a role in preventing or treating cancer.

The theory that vitamin D may reduce cancer risk is based in part on studies showing that vitamin D deficiency is associated with an increased prevalence of cancer and on evidence that vitamin D has some anti-cancer properties. But more research is needed to evaluate the role of sunlight-induced production of vitamin D in preventing cancer, according to the NCI.

The current information about vitamin D can be confusing. The skin makes vitamin D after exposure to ultraviolet radiation. Yet, many experts say that there is no safe amount of sun exposure because ultraviolet radiation can cause skin cancer. These potentially negative effects are likely cumulative over a person's lifetime.

The amount of vitamin D that may help prevent cancer, if any, isn't known. Also, the exact amount of sunlight needed to replenish the body's stores of vitamin D isn't known.

Until more is known, it's important to protect your skin from too much sun, according to the American Cancer Society. Getting enough vitamin D also is important. The safest way to increase your vitamin D levels is by taking a multivitamin that contains vitamin D.

Last Updated: 08/23/2005
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