To protect itself from the damaging effects of the sunlight, our skin increases its production of the dark brown pigment called melanin. The extra melanin makes the skin look darker or sun-tanned. In some cases, the sun causes an uneven increase in melanin production, which produces irregular colouring (pigmentation) of the skin.
Although most people love the warmth and light of the sun, too much sun exposure can signi8cantly 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, Iaky 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 Iuid-8lled 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.
Long-term changes in the skin’s collagen include photoaging in which the skin develops wrinkles and 8ne lines because of changes in the collagen of a deep layer of the skin called the dermis.
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.
Sun-damaged skin shows the following symptoms:
- Dry skin — The skin appears dry, fIaky and slightly more wrinkled than skin on other parts of your body that have not been exposed to the sun. Dry skin is also one of the most common causes of itching.
- Sunburn — Mild sunburn causes pain and redness on sun-exposed skin. In most cases, there are clear boundary lines where the skin has been protected from the sun by shirt sleeves, shorts, a bathing suit or other clothing. More severe cases of sunburn produce painful blisters.
- Actinic keratosis — An actinic keratosis appears as a small bump that feels like sandpaper or a persistent patch of scaly (peeling) skin that may have a jagged or even sharp surface and that has a pink, yellow, red or brownish tint. At 8rst, an actinic keratosis may be the size of a pimple. Rarely, an actinic keratosis may itch or be slightly tender.
- Long-term changes in the skin’s collagen — Symptoms of collagen changes include 8ne lines, deeper wrinkles, a thickened skin texture and easy bruising on sun-exposed areas, especially the back of the hands and forearms.
We can prevent sun-damaged skin by taking the following steps:
- Apply a sunscreen before going 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. if possible.
- Wear sunglasses with UV light protection.
- Wear long pants, a shirt with long sleeves and a hat with a wide brim.
- Photoaging and other collagen changes — Although it is not possible to reverse all of the effects of long-term sun damage, we may be able to improve the appearance of your skin by prescribing a derivative of vitamin A. Other options include chemical peels, laser resurfacing, microdermabrasion, in which the outer layer of skin is rubbed away with a special rotating brush or wheel. This allows new skin to grow in place of the old, sun-damaged skin. We may also be able to inject botulinum toxin ( Botox ) or a dermal 8ller to reduce wrinkles.
Sun damage may result in a permanent cosmetic concern. More important than appearance is the long-term impact of sun damage on your chances of developing skin cancer. The more unprotected sun exposure you have during your lifetime, the greater your risk of skin cancer, especially if you have a light complexion.