Age spots are caused by prolonged exposure to the sun and other forms of ultraviolet light. Age spots most often affect areas that are exposed to the sun including the shoulders, face, back of the hand and forehead, notes MedlinePlus.
Though they are called age spots, they are not always caused by aging. They usually occur when melanin production is accelerated due to ultraviolet light exposure. When the skin is exposed to this type of light, it produces melanin in order to protect the inner layers of the skin from exposure, notes Mayo Clinic.
A common cause of accelerated melanin production is aging. People that are well advanced in age are therefore likely to have this condition. Another cause of age spots is too much exposure to the sun. This is because the sun produces ultraviolet light, which may cause adverse effects to the body, hence why melanin is produced. The use of tanning lamps and tanning beds may equally contribute to development of these spots.
Doctors diagnose aging spots by taking patient history and physical examination of the skin. Once diagnosed, treatment can be done by the use of lasers to destroy melanin producing cells or cryosurgery, which freezes the spots by the use of nitrogen.