The twin on the right is a smoker. The twin on the left is a non-smoker.
"The study looked at other aging factors — alcohol consumption, stress and sunscreen use, for instance — and found they were similar in these sets of twins. It didn’t address changes in the twins’ living environment or diet.
“Smoking reduces the collagen formation, results in collagen degradation and reduces the skin circulation,” one doctor said.
“Additionally, nicotine reduces the skin thickness. All of these reduce skin elasticity and (cause) premature aging.” The study was published in the journal Plastic and Reconstructive Surgery."
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