Background: Despite many reports on the skin aging factors using non-invasive methods, there is a need to identify reliable skin aging factors obtained in sufficient subjects and in a properly controlled environment.
Objectives: To investigate the characteristics of facial skin of eight Asian countries and to confirm the aging parameters of 20- to 50-year-old Asians.
Methods: The subjects consisted of 5,205 healthy males and females ranged from 20 to 59 years-old in South Korea, Mongolia, Taiwan, Kazakhstan, Russia, Turkey, the Philippines, and China. Skin hydration, transepidermal water loss (TEWL), pore area, pH, elasticity, wrinkles, and skin color on the face were measured under the environmental conditions of specific relative temperature and humidity, controlled and maintained identically for each volunteer.
Results: Elasticity, pore area, wrinkles, skin color, and TEWL on the face were correlated with age, but skin hydration and pH were not correlated with age. Elasticity, pore, and wrinkles parameters showed higher r-values than others. The r-value of elasticity was -0.740 in R2, -0.436 in R5, and -0.539 in R7 (p <0.01). The r-value of pores and wrinkles were 0.523 and 0.502, respectively.
Conclusion: The present study suggests that the aging parameters of the facial skin that are highly correlated with early aging in 5,205 subjects are elasticity, area of pores, and wrinkles.