Risk Factors:

Exposure to Sun in Childhood. It is estimated that 50 - 80% of skin damage occurs in childhood and adolescence from intermittent, intense sun exposure that causes severe sunburns. In spite of this now well-known effect, many people still believe that a tan is a sign of good health in children. Even though many parents are concerned about sun exposure, they still rely too much on sunscreen and not enough on protective clothing.

The Elderly. Most people over 70 have at least one skin disorder, and many have three or four skin disorders. Everyone experiences skin changes as they age, but a long life is not the sole determinant of aging skin. Family history, genetics, and behavioral choices all have a profound impact on the onset of aging-skin symptoms.

Activities Leading to Overexposure to Sunlight and Ultraviolet Radiation

Of all the risk factors for aging skin, exposure to UV radiation from sunlight is by far the most serious. The vast majority of undesirable consequences of aging skin occur in individuals who are repetitively exposed to the sun, including the following:

• Outdoor workers, such as farmers, fishermen, construction workers, and lifeguards
• Outdoor enthusiasts
• Sunbathers
• People who regularly attend tanning salons or use tanning beds

Skin Types

Experts have devised a classification system for skin phototypes (SPTs) based on the sensitivity to sunlight. It ranges from SPT I (lightest skin plus other factors) to IV (darkest skin). People with skin types I and II are at highest risk for photoaging skin diseases, including cancer. It should be noted, however, that premature aging from sunlight can affect people of all skin shades.

Gender

The common belief is that women are at greater risk for wrinkles than men. Some evidence suggests, however, that given the same risk factors, men and women in the same age groups have comparable risks for skin photoaging. Some studies report that men are more likely than women to develop non-melanoma skin cancers.

Smokers

Heavy smokers are almost five times more likely to have wrinkled facial skin than nonsmokers, according to one study. The skin of smokers in areas of their bodies not exposed to sunlight also seems to age more rapidly compared to nonsmokers in the same age group. In fact, heavy smokers in their 40s often have facial wrinkles more like those of nonsmokers in their 60s.

Studies of identical twins have found smokers to have thinner skin (in some cases by as much as 40%), more severe wrinkles, and more gray hair than their nonsmoking twins. Cigarette smokers are also more prone to skin cancers, including squamous cell carcinoma and giant basal cell carcinoma. Research has found that women who smoke have much lower levels of vitamin E secretions in their skin. Vitamin E is an antioxidant that may help protect the skin from sun damage. [For more information, see In-Depth Report #41: Smoking.]