UVA rays contribute to skin damage to a lesser degree, but the rays are present throughout the day year-round. Eighty percent of lifetime sun exposure occurs before the age of 18. Severe sunburns at a young age dramatically increase a person's chances of developing skin cancer later in life. According to Margaret Tucker, chief of the genetic epidemiology branch at the National Cancer Institute, just one blistering sunburn raises the standard life time risk of developing melanoma about 50 percent. Ten severe sunburns raise the standard risk 400 percent.
Prevention Always use sunscreen or sunblock, even on overcast days.
Clouds do not block damaging UV rays. Sensitive areas include scalp, eyes, nose and cheekbones, ears, lips, back of neck and shoulders, and hands and feet. Products with zinc oxide, titanium dioxide, oxybenzone or avobenzone will provide stronger protection. Look for brands that protect against both UVB and UVA rays. For small children and infants, a total sunblock should be used.