<P> Moderate exposure to the sun contributes to the production of melanin and vitamin D by the body , but excessive exposure to ultraviolet rays has negative health effects , including sunburn and increased risk of skin cancer , as well as depressed immune system function and accelerated aging of the skin . Some people tan or sunburn more easily than others . This may be the result of different skin types and natural skin color , and these may be a result of genetics . </P>
<P> Moderate exposure to the sun contributes to the production of melanin and vitamin D by the body , but excessive exposure to ultraviolet rays has negative health effects , including sunburn and increased risk of skin cancer , as well as depressed immune system function and accelerated aging of the skin . Some people tan or sunburn more easily than others . This may be the result of different skin types and natural skin color , and these may be a result of genetics . </P>
what does the skin produce in response to sunlight exposure
what does the skin produce in response to sunlight exposure
melanin vitamin D
melanin vitamin D