Skin color of Koreans: statistical evaluation of affecting factors

BACKGROUND: The L*a*b* three-dimensional coordinate system is the most popular system used to measure skin color. The purpose of this study was to collect standard quantified data on Korean skin color using a chromameter CR-300, and to investigate the relationships among skin color and the general and individual factors that affect it. METHODS: The 600 subjects used in this study were selected using a three-stage proportionate stratified and quota sampling method. We examined the color of 12 body parts of each subject and calculated the E* value (total color difference between two objects). This study also analyzed factors that may affect skin color. RESULTS: The average L*a*b* values for the 12 body parts were 61.7462, 9.5618 and 17.0778, respectively. The site of lightest skin was the medial arm (L=63.9249), whereas the darkest was on the forehead (L=58.0044). Redness was highest on the cheek (a=11.8694) and lowest on the medial arm (a=8.1844). Skin color was lighter and more yellow in females than in males, whereas redness was higher in males. In the case of total color difference between two specific sites, the medial upper arm and forearm were the most similar (E=3.23), and the forehead and medial upper arm were the most different in color (E=7.99). CONCLUSION: The factors that significantly (P<0.01) influenced L* were sex, work place and sunbathing, factors that influenced a* were sex, work place and smoking; and the factors that influenced b* were sunbathing and age.