Other Factors Other environmental factors, including cigarette smoke and pollution, particularly ozone, may hasten chronologic aging by producing oxygen-free radicals. Rapid weight loss can also cause wrinkles by reducing the volume of fat cells that cushion the face. This not only makes a person look gaunt, but can cause the skin to sag. The vast majority of undesirable consequences of aging skin occur in individuals who are repetitively exposed to the sun, notably farmers, fishermen, construction workers, lifeguards, outdoor enthusiasts, and sun-worshippers. People who live in areas where the earth's protective ozone layer is thinning, namely in southern climates and at high altitudes, are more likely to have sun-damaged skin.
Ethnicity also influences a person's susceptibility to aging skin.
Individuals with fair complexions, and those who have blue, green, or gray eyes, and red or blond hair, are more susceptible to photoaging than are darker-skinned persons. Overall, African Americans develop fewer wrinkles, have fewer lesions, and experience less sagging of facial skin than do whites, presumably because the larger amount of melanin present in their skin helps block the penetration of UV radiation. Nonetheless, premature aging from sunlight can affect all ethnic groups. Cigarette smokers are more prone to wrinkles and skin cancers. According to one study, heavy smokers are almost five times as likely to have wrinkled facial skin than nonsmokers.