Although it\u2019s pleasant as you first experience sun warming your skin after the winter, over time, the sun causes damage to your body \u2013 including your immune system and particularly, your skin. Sun damage can make itself visible in a number of ways, from premature aging and discoloration of the skin (sometimes called \u201csun spots\u201d) to, in more severe cases, skin cancer and melanoma. Sun damage is caused by Ultraviolet radiation:\nWhat is Ultraviolet Radiation?\nUltraviolet (UV) radiation is invisible rays that are part of the energy that comes from the sun. There are three types of UV radiation \u2013 UVA, UVB, and UVC.\nUV rays are measured by a numbered index. Local news and weather channels will tell you what the level is expected to reach each day:\n\n\n\n\n0-2: Low risk\nSunscreen\nSunglasses\n\n\n3-5: Medium risk\nSunscreen\nSunglasses\nHat\n\n\n\n\n6-7: High risk\nSunscreen\nSunglasses\nHat\nShade\n\n\n7-10: Very high risk\nSunscreen\nSunglasses\nHat\nShade\n\n\n\n\n11+: Extreme risk\nSunscreen\nSunglasses\nHat\nShade\nStay indoors, especially from 10 a.m. to 4 p.m.\n\n\n\n\nWhy Is It Important to be Protected?\nUV Radiation, in all of its forms, can cause:\n\nMelanoma and several other types of skin cancers\nSun damage that prematurely ages the skin\nPremature aging\nEye damage\nAltered function of the immune system\n\nWhen Is the Most Dangerous Time for UV Exposure or Sun Damage?\nMost of the day\u2019s UV rays from the sun come between 9 a.m. and 5 p.m., and almost a third of the day\u2019s rays come between 11 a.m. and 1 p.m., according to the American Cancer Society. UV rays are dangerous throughout the year, but they are the strongest during the summer.\nWhere Does UV Radiation Come From and Where Should I Be Protected?\nUV radiation comes mostly from the sun and tanning beds. You may also be exposed to UV radiation via special lamps or lasers that are used to treat skin conditions such as psoriasis. Any part of your skin that is exposed to the sun should be protected by:\n\nWearing sunscreen with at least a SPF of 30\nSeeking shade\nWearing protective clothing (hat and sunglasses)\n\nWho Is most Affected by UV Exposure?\nEveryone should be protected from UV exposure. Sunscreen should especially be applied to children and parents should also consider protective clothing for little ones spending time in the sun. Babies younger than six months should be protected using hats and clothing and should be kept out of direct sunlight. Only use sunscreen on small areas that are exposed if shade or clothing is not available.\nIf you have a sun spot or mole that looks unusual, you may want to have it looked at to be sure it is benign. Please visit the UPMC Hillman Cancer Center website and request an appointment online or call 412-647-2811.