Genes, lifestyle factors influence skin aging
MedWire News: European scientists have identified a range of factors that influence skin aging, confirming that heavy smoking promotes aging whereas use of sunscreen has a protective effect.
They also found that a gene that controls skin pigmentation can either promote or protect against aging, depending on which form of the gene the person has.
Dr Mariano Suppa (University of Leeds, UK) and co-workers studied facial photographs of 1341 middle-aged men and women. All gave detailed information about their lifestyles and medical history and had blood samples analyzed for genetic variations.
Each photograph was assessed for common features of skin aging (wrinkles, vascularity, and blotchy pigmentation) and graded for the levels of sun-associated skin aging (photoaging) in the delicate area around the eyes.
Dr Suppa and colleagues found that wrinkles, vascularity, and blotchy pigmentation were all associated with older age, and wrinkles in particular were worse in older individuals and heavy smokers.
Moderate smokers did not have worse wrinkles than nonsmokers, however.
Vascularity - or the presence of "spider" or "thread" veins on the surface of the skin - tended to be worse in men, older individuals, people who spent longer in the sun each day, people who were overweight, and smokers.
Interestingly, certain variants of a gene called "melanocortin 1 receptor" (MC1R) were also associated with more severe spider veins.
The MC1R gene is involved in determining people's hair and skin color, and works by controlling the production of melanin, a pigment that can be brown, red, tan, or yellowish in color.
Blotchy pigmentation, or "sun spots," was worse in older individuals and in men, those with higher levels of education, and people who reported higher levels of sun exposure.
However, two factors protected against blotchy pigmentation, including a different variant in the MC1R gene and more frequent use of sunscreen.
The researchers say this is one of the first studies to investigate factors that influence skin aging, and suggest that increased vascularity "would appear to be the best biomarker of regular sun exposure."
Writing in the British Journal of Dermatology, they conclude: "Heavy smoking is associated with wrinkling but moderate smoking less convincingly so. Sunscreen use shows evidence of a protective role for skin ageing."
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By Joanna Lyford