It is a common belief that smiling makes people appear younger.

Empirical findings in an Israeli-Canadian study, however, seem to prove that smiling faces are actually perceived as older than are faces with a deadpan or surprised expression.

Researchers at Ben-Gurion University (BGU) of the Negev and Western University in Canada revealed their unexpected findings in the May 8 edition of Psychonomic Bulletin and Review.

“Popular media promotes the idea that smiling makes you look younger,” said Prof. Tzvi Ganel, head of the Laboratory for Visual Perception and Action in BGU’s department of psychology. “Look at all of the smiling faces in skincare and dental ads. How many of us post smiling faces on social media?”

Working with Prof. Melvyn Goodale, director of the Brain and Mind Institute at Western University in Canada. Ganel conducted a series of experiments intended to gauge age perception based on facial expressions.

Forty BGU student participants were shown images of people and asked to rank them from oldest to youngest. They were shown pictures of smiling faces, neutral expressions and surprised looks.

Participants ranked the smiling faces as the oldest, followed by neutral expressions. They ranked surprised expressions as the youngest.

And yet when asked to recall their reactions after the experiment, study participants erroneously remembered identifying smiling faces as appearing younger than neutral ones.

“Ironically, we discovered that the same person can believe that smiling makes you appear younger and judge smiling faces older than neutral ones,” said Goodale.

What accounts for this finding?

The researchers believe that smiling makes a person look older because of the wrinkle lines that form around the eyes. A surprised face lifts and pulls the skin backward, smoothing any potential age-related wrinkles.

“We proposed that the ‘aging’ effect of smiling originates from people’s inability to ignore the wrinkles that form around the eyes during smiling,” the researchers write.

The study suggests that despite first impressions, people still believe that smiling makes one appear younger. “This undoubtedly reflects the association of smiling with many positive characteristics,” the scientists concluded.