Aging Skin
The natural process of skin turnover, which varies from person-to-person based on their exposure to age-accelerating stimuli.
Genetically programmed chronologic aging causes biochemical changes in collagen and elastin, the connective tissues that give skin its firmness and elasticity. The genetic program for each person is different, so the loss of skin firmness and elasticity occurs at different rates and different times in one individual as compared with another.
As skin becomes less elastic, it also becomes drier. Underlying fat padding begins to disappear. With loss of underlying support by fat padding and connective tissues, the skin begins to sag. It looks less supple, and wrinkles form. The skin may be itchy with increased dryness. A cut may heal more slowly.
An important accelerator of skin aging is caused by photoaging; the effect of chronic and excessive sun exposure on the skin. Photoaging interacts with chronologic aging and may appear to hasten the process of chronologic aging. In fact, photoaging may be responsible for the majority of age-associated changes in the skin’s appearance: mottled pigmentation, surface roughness, fine wrinkles that disappear when stretched, “age” or “liver” spots (lentigines) on the hands, and dilated blood vessels. Chronic sun exposure is a major risk factor for skin cancers—basal cell carcinoma, squamous cell carcinoma and melanoma.
The effects of photoaging accumulate over years of chronic sun exposure. At first, the effects may be invisible to the casual glance, even while they are on the increase. Photos taken with ultraviolet light will dramatically reveal the accumulative effects of chronic sun exposure.
Additionally, cigarette smoking can contribute to aging effects by the biochemical changes it brings about in skin tissues.