Could your smile predict your life span?

What can you tell about a person from their ‘photo face’?

A study in the journal Psychological Science suggests we can predict from a photograph whether someone is likely to live longer. The secret is in our smile, say Ernest Abel and Michael Kruger.

They asked volunteers to rate the attractiveness and ‘smile intensity’ of more than 200 baseball players, from photos featured in the 1952 Baseball Register. Of the players who had died, the ones rated as ‘Duchenne smilers’ (named after the neurologist who first noted that a genuine smile involves the eyes as well as the mouth) lived to an average of 79.9 years. Partial smilers averaged 75 years, while non-smilers only made it to 72.9.

Why might this be? ‘Smile intensity reflects an underlying emotional disposition,’ say the researchers. In other words, the happiest of us smile more and, apparently, live up to seven years longer.