Pigmentation in African American skin decreases with skin aging

Background Tristimulus colorimetry, which uses the Commission Internationale de l’Eclairage L*a*b* model to quantify color, has previously been used to analyze pigmentation and erythema in human skin; however, colorimetry of African American skin is not well characterized. Objective We sought to analyze skin color patterns in African Americans and compare them with those of Caucasians. Methods Colorimetry readings of the sun-protected buttock and sun-exposed back of forearm were taken from 40 Caucasian and 43 African American participants from March 2011 through August 2015. African American participants also completed a lifestyle questionnaire. Correlation coefficients, paired t tests, and multivariable linear regression analyses were used for statistical comparisons. Results Forearm skin was lighter in African Americans ages 65 years and older versus 18 to 30 years ( P = .02) but darker in Caucasians ages 65 years or older versus 18 to 30 years ( P = .03). In African Americans ages 18 to 30 years, the buttock was darker than the forearm ( P