Study of twins shows smoking causes premature aging
Researchers from the Western Reserve University and University Hospitals of Cleveland found that smoking, does, indeed, speed up the aging process. A new study shows that twins who smoke show more signs of premature facial aging than their identical twins who are non-smokers, or smoked at least five years less.
For their research, published in the journal Plastic and Reconstructive Surgery, the scientists recruited 79 pairs of identical twins who attended the Twins Day Festival in Twinsburg, Ohio. Of these pairs, 57 were women and the average age for all pairs was 48.
One twin within each pair smoked, while the other had smoked for at least five years less, or did not smoke at all. The average difference in smoking history between the twins who both smoked was 13 years. All twins were required to have professional photographs taken in close-up of their face, as well as complete questionnaires regarding their medical history and lifestyle.
In order to determine specific areas of facial aging that may be affected by smoking, experts in monitoring the signs of aging analyzed the twins' facial features from the photographs--without knowing details of their smoking history. They studied the gradients of the twins' wrinkles and other facial features that may be affected by aging, including the presence of bags under the eyes and lower eyelid skin discoloration. Each type of wrinkle and age-related feature was given a score for its severity.
The findings revealed that twins who smoked had significantly worse scores on the majority of the measures for facial aging. Smokers showed more sagging of the upper eyelids and more bags of the lower eyelids and under the eyes. They also had higher scores for facial wrinkles, specifically wrinkling of the upper and lower lips, sagging jowls, and more pronounced lines between the nose and mouth. However, the study authors found that twins who smoked showed fewer differences in aging of the upper part of the face, including crow's feet around the eyes and forehead lines.
When the judges were asked to choose which twin they believed looked older from the photographs of the pairs in which one was a non-smoker, they chose the smoking twin 57 percent of the time. In twins who both smoked, the judges identified the twin who smoked for longer as appearing older 63.7 percent of the time. The study authors noted that although their findings demonstrate that smoking is a cause of facial aging, and they found it particularly interesting that in cases where both twins smoked, there was a significant difference in facial aging based on who had smoked longer.
The researchers said that as well as showing how smoking can lead to premature facial aging, the study may also provide clues as to how smoking causes aging at a cellular level, as the effects appeared different for various facial features.