London - Want to look your best in a photograph? Try turning the other cheek.

When it comes to attractiveness, it seems our left side is our good side – or in other words, pictures taken from the left cast us in a more appealing light than those taken from the right.

The discovery by scientists in the US may explain why portrait artists have traditionally tended to paint the left profile of subjects such as the Mona Lisa and the Laughing Cavalier.

According to James Schirillo and Kelsey Blackburn, from Wake Forest University in North Carolina, the left side of the face tends to “exhibit a greater intensity of emotion, which observers find more aesthetically pleasing”.

“So if you’re smiling, you’re going to get a bigger smile on the left side of your face than on the right side,” explained Dr Schirillo.

In the study, published in the academic journal Experimental Brain Research, 37 university students were asked to rate the attractiveness of ten pictures of men and ten of women.

Photos were presented both as originally taken and in mirror image so the right side appeared to be the left.

The researchers found that the photos showing left sides of faces were rated more “pleasant”. The effect held true even when they had been reversed, so pictures which appeared to show the right side were favoured.

Participants’ pupils dilated more – an unconscious sign of interest – when viewing the photos taken from the left, whether the images had been reversed or not.

The study’s authors said their findings added weight to the theory that the right hemisphere of the brain, which controls the left side of the face, has more to do with emotions than the left hemisphere.

Some celebrities are already wise to the benefits of the ‘good’ side. Barbra Streisand famously insists on being photographed from her left, once having the set of a US chat show moved around so she would be facing the audience in her preferred direction.

“People should turn slightly so that they show more of their left than right cheek when being photographed,” said Dr Schirillo. “Others will find these images more appealing.” - Daily Mail