As we enter the "selfie" age -- or perhaps more accurately the selfie "craze" -- a new study suggests that men who post lots of selfies show an increased tendency for narcissism and psychopathy.

Men who upload a higher number of online selfies to sites like Facebook or Instagram may be more likely to exhibit anti-social traits, researchers at Ohio State University say.

Those who spend time carefully editing those selfies before posting them, an indication of how much they wish to emphasize their appearance, score even higher in self-objectification and narcissism, they report in the journal Personality and Individual Differences.

"It's not surprising that men who post a lot of selfies and spend more time editing them are more narcissistic, but this is the first time it has actually been confirmed in a study," said study lead author and professor of communications Jesse Fox.

In the study, 800 men aged 18 to 40 years old were surveyed about the photo posting activity on social media sites, while also completing standard questionnaires for anti-social behavior and self-objectification.

Narcissism and psychopathy are different, the researchers noted. Narcissists believe they are smarter, better and more attractive than others, while psychopaths display a lack of regard or empathy for other people and have a tendency to indulge in impulsive behavior.

In addition to being asked about the frequency with which they posted selfies, the men in the study were questioned about whether they edited them before posting, by cropping or using filters or photo editing software.

"Most people don't think that men even do that sort of thing, but they definitely do," Fox said.

While the findings indicate posting many photos is related to both narcissism and psychopathy, psychopathy was not linked to a tendency to edit photos, she said.

"That makes sense because psychopathy is characterized by impulsivity. They are going to snap the photos and put them online right away. They want to see themselves. They don't want to spend time editing," she said.

The researchers emphasize their findings don't mean men posting a lot of selfies are necessarily narcissists or psychopaths; while the men surveyed showed higher than average levels of these anti-social characteristics, they were still within what is considered a normal range of behavior.

Self-objectification -- the notion that one's self-worth is based on one's appearance, rather than on other positive characteristics -- has rarely been studied in heterosexual men, according to Fox.

"We know that self-objectification leads to a lot of terrible things, like depression and eating disorders in women," she said.

"With the growing use of social networks, everyone is more concerned with their appearance. That means self-objectification may become a bigger problem for men, as well as for women."