In case anyone needed proof, a new study supports the widely held perception: Celebrities are more in love with themselves than the average person is.

That is the conclusion drawn by Drew Pinsky and S. Mark Young of the University of Southern California, whose study of 200 celebrities will appear in the Journal of Research in Personality.

It is not the entertainment industry that turns stars into narcissists, the study found. Rather, it suggests, the self-adoring seek jobs in show business.

The study, whose subjects were all celebrities from Pinsky's 'Loveline' radio show, found that reality TV stars were the most narcissistic of all celebrities. Female stars were also more likely than their male counterparts to exhibit narcissistic traits.

It's "common sense" that celebrities are narcissists, said Jeremy Ritzlin, a longtime Hollywood psychologist who has not seen the study.

"Narcissism is really being in love with yourself," he said. "So it would be natural for narcissists to gravitate toward the spotlight, where other people will also think highly of them."

Pinsky, an assistant clinical professor of psychiatry at USC's Keck School of Medicine, said narcissists crave attention, are overconfident, behave erratically and lack empathy.

"However, they are well-liked, especially on first meeting, are extroverted and perform well in public," added Pinsky, who has hosted the radio show "Loveline" for 20 years.

Celebrity guests appearing on the program were randomly chosen to participate in the study. They anonymously took the Narcissistic Personality Inventory test, which rates self-love levels based on seven components: superiority, exhibitionism, entitlement, vanity, authority, exploitativeness, and self-sufficiency.