Overexposure to ultraviolet, or UV, radiation from the sun has been linked to a host of major health problems. According to the U.S. Environmental Protection Agency, unprotected exposure to UV radiation is the most preventable risk factor for skin cancer, which the Canadian Skin Cancer Foundation notes is responsible for one in every three cancers diagnosed across the globe each year. Overexposure to UV radiation can also contribute to premature aging and other skin damage. When the skin is overexposed to UV radiation, actinic keratoses may develop on areas of the body that were exposed to the sun, including the face, hands and forearms. Actinic keratoses have a raised, reddish appearance and may be rough in texture. Vision problems may also arise as a result of overexposure to UV radiation. The EPA notes that research has indicated that exposure to UV radiation increases a person's risk for developing certain types of cataracts, a medical condition in which the lens of the eye grows increasingly opaque. Overexposure to UV radiation may also contribute to degeneration of the macula, the region of the retina with the greatest visual acuity. UV-protective eyeglasses, contact lenses and sunglasses can protect people from the type of eye damage that arises from overexposure to UV radiation. The body's immune system may also be adversely affected by overexposure to UV radiation, making a person more vulnerable to infections and even cancer.