Jessica L. Tracy / UBC Examples of stimulus photos used in Happy Guys Finish Last: The Impact of Emotion Expressions on Sexual Attraction

Men, if you’re trying to lure the ladies with a photograph, make like James Dean and brood. Women are turned off by guys who smile, according to a new study published in the American Psychological Association’s journal Emotion.

Men, however, were most attracted to photos of smiling women, the study found. And both men and women said they were attracted to people with a look of shame. The findings may have something to say about how non-verbal cues like posture and expression affect initial sexual attraction in both genders.

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Surveying more than 1,084 heterosexual men and women over the course of four experiments, researchers from the University of British Columbia asked people to rate the sexual attractiveness of people of the opposite sex based on a photo. The pictures were of male or female models making one of four facial expressions: happy (wide smile), proud (lifted chin, puffed up chest), ashamed (downcast eyes, lowered head) or neutral. The participants used a 9-point scale, with 1 being unattractive and 9 extremely attractive.

Women rated smiling men the lowest, with shame-faced men higher than that. Men with neutral expressions or puffed-up with pride scored highest. “So to the extent that men think that smiling is a good thing to do if they want to be found sexually attractive, our findings suggest that’s not the case,” Jessica Tracy, a University of British Columbia psychology professor who directed the study, told Reuters.

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Meanwhile, male viewers rated prideful and neutral facial expressions on women as least desirable. They were most sexually attracted to women with big smiles or shamed expressions on their faces. Reuters reported:

The researchers admit they are not sure why men and women reacted differently to smiles. In a man, a big smile may make him appear too feminine or more desperate for sex. The study also adds fuel to the notion that women are attracted to bad boys. “Women are attracted to guys like James Dean, Edward the vampire. The guys who are flawed, but who know it and are tortured by it,” Tracy said. A slightly downcast expression of shame is an appeasement gesture that hints at a need for sympathy. Men also found sexual attractiveness in women whose expressions and body language hinted at shame.

But before you go around frowning at every alluring prospect at the bar, remember that the results apply only to initial reactions to sexual attractiveness in photos. As such, they’re probably only useful for helping you choose an online profile picture.

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As far as real-world, long-term relationships go, people look for a lot more than sexual attractiveness. “How nice a person is, is a big thing,” Tracy said.