Sunburnt back, arms and neck of a woman whose skin has suffered from over-exposure to the ultraviolet (UV) radiation in direct sunlight. UV radiation destroys cells in the outer skin layer and damages the tiny blood vessels beneath. This is a first- degree burn, one that only affects the top skin layer, the epidermis. Sunburn is most common in fair-skinned people, whose skin lacks the protective pigment melanin. Repeated exposure prematurely ages the skin and increases the risk of skin cancer. Calamine lotion and painkillers help to soothe sunburnt skin.