Twins prove it: lifestyle affects aging
NEW YORK, Dec 17 (Reuters Health) -- A study of the aging process in identical twins shows that those who live the hardest, age the fastest, researchers report.
Sun exposure, smoking, stress, alcohol intake, diet, exercise, and general health can all affect the aging process, according to the findings published in the December issue of the Annals of Plastic Surgery.
Researchers at Columbia University in New York collected photographs and data on lifestyle from 34 sets of identical twins between the ages of 45 and 75. The investigators also examined microscopic differences in skin taken from around the ear in 7 sets of twins. Identical twins were studied because they have the same genes, thus lifestyle factors that affect aging can be clearly seen, distinct from the genetic influence on aging.
Dr. Darrick E. Antell and colleagues asked the twins specifically about sun exposure, smoking history, health history in general including use of medications, alcohol use, exercise and the amount of stress in their lives.
The research team found that wrinkle patterns, especially around the eyes, were identical in the twins, "but the depth and severity of wrinkles, amount of excess skin and quality of skin texture varied." The differences between twins in signs of aging "differed in direct proportion to the relative differences in lifestyle within that twin set."
Antell's team notes that smoking impairs circulation to the skin, causes discoloration of the skin and collagen breakdown. They add that "more than 90% of the skin damage seen today is produced by sun exposure," which also causes "significant" collagen breakdown, large pores, age spots, and skin cancer.
In one set of twins, the sibling with a 40-year history of smoking had approximately 50% more gray hair than his nonsmoking twin. Other than smoking history, the two had "virtually identical" lifestyles, the authors explain. The least difference in aging occurred in a pair of 64-year-old Mennonite sisters "who lived virtually identical, vice-free lives."
"Our current twin study has shown that, when controlling for the effects of genetic predisposition, lifestyle can greatly influence a person's physical appearance and augment the effects of aging," Antell and colleagues conclude.