A new study of Canadian university students suggests Facebook is a magnet for narcissists and people with low self-esteem.
Participants who were deemed narcissistic, and others shown to have low self-esteem, spent more time on the massively popular social-networking website, the York University research found.
Researcher Soraya Mehdizadeh also found that these people use Facebook as a means of self-promotion.
Mehdizadeh admits the sample group of just 100 participants from such a specific demographic doesn't necessarily reflect everybody who uses Facebook.
But she expects the findings to prompt the site's users, who number roughly 16 million in Canada, to take a closer look at themselves - and their Facebook "friends."
"I think people get sort of defensive about it, like: 'I don't use my Facebook for that reason' - because it's a label that you don't want to be slapped with," she said Tuesday in an interview.
"I don't know if self-fulfilling prophecy is the word, but it's sort of like you've been believing it at the back of your head . . . and it's like, 'I knew they were a narcissist.' "
The surveys studied the online habits and personalities of 50 female and 50 male Facebook users between the ages of 18 and 25.
Participants, all York students, took psychological tests that measured their sense of self-esteem and assessed their levels of narcissism. Sections of their Facebook pages were also examined.
The study defined narcissism as a pervasive pattern of grandiosity, need for admiration, and an exaggerated sense of self-importance.
Self-esteem was identified as a person's overall self-evaluation or their worth.
Students who scored lower on the self-esteem scale, as well as those rated higher on the narcissism test, were correlated with a greater number of Facebook checks per day and more time spent on it.
The surveys were conducted two years ago. The findings, published last month in the journal Cyberpsychology, Behavior, and Social Networking, also suggest differences between the men and women who use Facebook.
The women surveyed were more likely to self-promote through a carefully selected main photo that might offer a flashy, doctored or revealing image of their physical appearance.
Male participants promoted themselves more though written postings describing themselves in the "About Me" or "Notes" sections.
"It's really interesting to look at the differences between the online self and the off-line self and to sort of bridge the gap between the two," Mehdizadeh said of the research, part of her undergraduate thesis.
She painted Facebook as an ideal setting for narcissists who can monitor how many "friends" they have.
It can also serve as a "social lubricant" for those with low self-esteem, since it's so easy for them to connect with so many people.
For example, Facebook friends can boost the confidence of someone who doesn't feel good about their physical appearance by posting flattering comments on photos, she added.
"That's obviously something that might help someone deal with their low self-esteem," said Mehdizadeh, who is now preparing for medical school.
"If (Facebook) would improve their self-esteem, what great benefits that would have to the health and well-being of people who use the site."
Facebook said in July that it had 500 million users worldwide, up from the 250 million users it had the year before.
Canada eclipsed the 16-million users mark in May, according to research firm Inside Network.
Does this mean that everyone who spends more than three hours a day on Facebook is narcissitic or has low self-esteem?
"Maybe not," Mehdizadeh says.
"But what this study does meaningfully achieve, in my opinion, is a contribution to the already existing literature."
Still, questions remain in a relatively new area of psychology, she added.
"Is it that narcissists are more likely to use Facebook, or people who use Facebook are more likely to become narcissists?"