The influence of ethnic origin on the skin photoageing: Nepalese study.

Ethnic and genetic differences modify skin structure and function. Skin photoageing is becoming one of the most studied cosmetological topics. However, there are relatively few data available to evaluate the effect of ethnic skin origin on the degree of photoageing, particularly among people inhabiting sunny and hot climate as in South Asia. Two hundred and forty participants, enrolled in the study conducted in Pokhara valley, Nepal, were classified into four different age categories viz. below 30, 30-50, 50-60 and above 60 years. Participants answered the questioner regarding their age, gender, ethnic origin, occupation, skin characteristics, lifestyle factors, type of cosmetic and skin care products used, drug treatment and personal skin condition evaluation. Skin hyperpigmentation and the degree of wrinkling, the two most important parameters related to photoageing, were particularly evaluated in two ethnic groups, namely Aryan-origin and Mongolian-origin participants. The study showed that Aryan-origin ethnic skin was more wrinkled and darker than that of Mongolian. Male skin was found to be darker than the female skin, which might be the result of the use of sun-protective cosmetic products among women. Smoking was found to increase the degree of wrinkling; however, no differences related to ethnic origin in relation to smoking were observed. This study indicates the need to further evaluate the differences in skin response to daily exposure to strong sun among various ethnic-origin inhabitants.