Is beauty really only skin deep? Skin is a big part of beauty, but it’s not all superficial. We use skin appearance to make judgments about what’s going on underneath.

In this study, researchers cropped photographs of cheek skin from 170 women and girls, ages 11 to 76. They asked 353 men and women to rate each cheek sample for attractiveness, health and youth. They also asked them to guess the age of the person in the photograph (from no more than a cheek, mind you).

Raters’ guesses about the ages of the subjects tended to be accurate—and the older the subject behind the sample was, the less likely they were to be rated healthy, attractive and youthful.

Still, one factor trumped age: The skin samples with even tone and texture were rated as younger, healthier and more attractive. Even tone and texture are signs of good health and minimal sun damage—no wonder we find it so lovely!