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Vitamin D, ultraviolet exposure, and skin cancer in the elderly
Marjam Jeanette Barysch1, Günther F Hofbauer, Reinhard Dummer
1Department of Dermatology, University Hospital Zurich, Zurich, Switzerland.
Abstract:
Ultraviolet (UV) radiation has both beneficial and harmful effects on the human body. Its most important beneficial effect may be vitamin D production in the skin, also known as vitamin D photosynthesis. This is of particular interest for the elderly who often show vitamin D-deficiency. Intentional UV exposure has been recommended by different institutions in order to increase vitamin D levels. Nevertheless, UV radiation directly causes DNA damage and is verifiably responsible for carcinogenesis, potentially resulting in lethal skin cancers. Unfortunately, skin cancer incidence is rising worldwide, and there is still a lack of appropriate treatment for metastasized types. The only proven and avoidable risk factor is UV radiation. It has been shown that the earlier UV protection is started, the greater the benefit in terms of skin cancer prevention. Nevertheless, even if UV protection is started at older ages, individuals will benefit measurably. Because UV radiation is neither a reliable nor a safe method of achieving healthy vitamin D levels, intentional UV radiation is not recommended to increase vitamin D levels. In order to prevent skin cancer, UV protection is to be conducted as commonly recommended, by minimizing sun exposure, and especially sunburn, with appropriate sun protective behaviors, e.g. usage of sunscreen and clothing (hat, sunglasses, long sleeves, and pants). Infants must be protected with extra care. Tanning beds must be avoided.
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