Age is a primary social dimension. We behave differently toward people as a function of how old we perceive them to be. Age perception relies on cues that are correlated with age, such as wrinkles. Here we report that aspects of facial contrast–the contrast between facial features and the surrounding skin–decreased with age in a large sample of adult Caucasian females. These same aspects of facial contrast were also significantly correlated with the perceived age of the faces. Individual faces were perceived as younger when these aspects of facial contrast were artificially increased, but older when these aspects of facial contrast were artificially decreased. These findings show that facial contrast plays a role in age perception, and that faces with greater facial contrast look younger. Because facial contrast is increased by typical cosmetics use, we infer that cosmetics function in part by making the face appear younger.

Redness or yellowness of the sclera (the light part of the eye) are known signs of illness, as is looking older than one's actual age. Here we report that the color of the sclera is related to age in a large sample of adult Caucasian females. Specifically, older faces have sclera that are more dark, red, and yellow than younger faces. A subset of these faces were manipulated to increase or decrease the darkness, redness, or yellowness of the sclera. Faces with decreased sclera darkness, redness, or yellowness were perceived to be younger than faces with increased sclera darkness, redness, or yellowness. Further, these manipulations also caused the faces to be perceived as more or less healthy, and more or less attractive. These findings show that sclera coloration is a cue for the perception of age, health, and attractiveness that is rooted in the physical changes that occur with age.

Makeup accentuates three youth-related visual features - skin homogeneity, facial contrast, and facial feature size. By manipulating these visual features, makeup should make faces appear younger. We tested this hypothesis in an experiment in which participants estimated the age of carefully controlled photographs of faces with and without makeup. We found that 40- and especially 50-year-old women did appear significantly younger when wearing makeup. Contrary to our hypothesis, 30-year-old women looked no different in age with or without makeup, while 20-year-old women looked older with makeup. Two further studies replicated these results, finding that makeup made middle-aged women look younger, but made young women look older. Seeking to better understand why makeup makes young women look older, we ran a final study and found evidence that people associate makeup use with adulthood. By activating associations with adulthood, makeup may provide an upward bias on age estimations of women who are not clearly adult. We propose that makeup affects social perceptions through bottom-up routes, by modifying visual cues such as facial contrast, facial feature size, and skin homogeneity, and also through top-down routes, by activating social representations and norms associated with makeup use.