What Is It?
Although most people love the warmth and light of the sun, too much sun exposure can significantly damage human skin. The sun’s heat dries out areas of unprotected skin and depletes the skin’s supply of natural lubricating oils. In addition, the sun’s ultraviolet (UV) radiation can cause burning and long-term changes in the skin’s structure.
The most common types of sun damage to the skin are:
• Dry skin — Sun-exposed skin can gradually lose moisture and essential oils, making it appear dry, flaky and prematurely wrinkled, even in younger people.
• Sunburn — Sunburn is the common name for the skin injury that appears immediately after the skin is exposed to UV radiation. Mild sunburn causes only painful reddening of the skin, but more severe cases can produce tiny fluid-filled bumps (vesicles) or larger blisters.
• Actinic keratosis — This is a tiny bump that feels like sandpaper or a small, scaly patch of sun-damaged skin that has a pink, red, yellow or brownish tint. Unlike suntan markings or sunburns, an actinic keratosis does not usually go away unless it is frozen, chemically treated or removed by a doctor. An actinic keratosis develops in areas of skin that have undergone repeated or long-term exposure to the sun’s UV light, and it is a warning sign of increased risk of skin cancer. About 10% to 15% of actinic keratoses eventually change into squamous cell cancers of the skin.
• Long-term changes in the skin’s collagen (a structural protein) — These changes include photoaging (premature aging of the skin because of sun exposure) and actinic purpura (bleeding from fragile blood vessels beneath the skin surface). In photoaging, the skin develops wrinkles and fine lines because of changes in the collagen of a deep layer of the skin called the dermis. In actinic purpura, UV radiation damages the structural collagen that supports the walls of the skin’s tiny blood vessels. Particularly in older people, this collagen damage makes blood vessels more fragile and more likely to rupture following a slight impact.
Over a lifetime, repeated episodes of sunburn and unprotected sun exposure can increase a person’s risk of malignant melanoma and other forms of skin cancer. As a rule, if you have fair skin and light eyes, you are at greater risk of sun-related skin damage and skin cancers. This is because your skin contains less of a dark pigment called melanin, which helps to protect the skin from the effects of UV radiation.
You can help to prevent sun-damaged skin by taking the following steps:
• Apply a sunscreen before you go outdoors. Choose a water-resistant sunscreen that has a sun protection factor (SPF) of 30 or above, with a broad spectrum of protection against both UV-A and UV-B rays. Be sure to reapply often to avoid sweating off or washing off the sunscreen.
• Use a sunblock on your lips. Choose a product that has been specially formulated for the lips, with a sun protection factor of 20 or more.
• Limit your time outdoors when the sun is at its peak (from about 10 a.m. to 3 p.m. in most parts of the continental United States).
• Wear sunglasses with UV light protection.
• Wear long pants, a shirt with long sleeves and a hat with a wide brim.
• Be aware that some medicines and skin care products can increase your skin’s risk of UV damage. These include certain antibiotics, as well as some prescription medicines that are used to treat psychiatric illness, high blood pressure, heart failure, acne and allergies. If you are taking a prescription medication and you normally spend a great deal of time outdoors, ask your health care professional whether you should take any special precautions to avoid sun exposure. Also, be aware that certain nonprescription skin care products containing alpha-hydroxy acids can make your skin more vulnerable to damage from sunlight.
To help detect actinic keratoses and other skin abnormalities in their earliest stages, examine your entire skin surface thoroughly every one to two months. Check for patches of discolored or scaly skin, moles, small pearly nodules, sores and other skin abnormalities on all parts of your body, including your scalp and genitals. Use a mirror to inspect harder-to-see areas of your back, shoulders, upper arms, buttocks and the soles of your feet. People who have numerous actinic keratoses should have their skin checked by a doctor at least twice a year.