Background: Few comparative data are available on age-related changes in skin color among different ethnic groups. The aim of the study was to measure and analyze the skin color and color heterogeneity in four different ethnic groups living in the same local environment and to determine the effects of age on these skin color characteristics.
Methods: Female volunteers (385) from four ethnic populations (African-American, Caucasian, Chinese and Mexicans) living in the same city were enrolled after informed consent. Skin color was measured on two facial areas, forehead and cheek. The subjects were further divided into six age ranges: 19-30, 31-40, 41-50, 51-60, 61-70 and 71-87 years to determine any age-related effects on the skin color and color heterogeneity in both areas.
Results: According to the L(*)a(*)b(*) CIE system, clarity (fairness/lightness) was found to be lower in the African-American group whereas the hue was lower in Caucasians, which means more red skin. A clear, statistically significant darkening of the skin with age was observed in all ethnic groups, while evidence of yellowing of the skin was shown in the Chinese volunteers. Overall, the skin color of the face of African-Americans was more heterogeneous than in the other ethnic groups, but showed the least increase with age.
Conclusion: Our study revealed interesting differences in skin color and color heterogeneity with respect to ethnicity and age-related alterations. Data obtained are very useful in improving our knowledge about the skin of people of different origins and helps in the development of specific cosmetic products that are well adapted to all these populations.