Does it really pay to be beautiful?

Feb. 16 (UPI) -- Many studies have documented the so-called "beauty premium" -- or its counter, the "ugliness penalty" -- a social phenomenon suggesting beautiful people are paid more than their less attractive peers.

New research suggests these studies have ignored the influence of separate but related factors like health, intelligence and important personality traits.

Satoshi Kanazawa, an evolutionary psychologist at the London School of Economics and Political Science, and Mary Still, a professor of marketing and management at the University of Massachusetts Boston, analyzed data from the National Longitudinal Survey of Adolescent Health, a study that included periodic measurements of participants' physical attractiveness during a 13-year span. The survey also included employment and salary data, as well as measures of health, intelligence and personality traits.

Their analysis showed high-earning attractive people tended to be healthier and more intelligent, as well as more conscientious, extraverted and less neurotic.

"Physically more attractive workers may earn more, not necessarily because they are more beautiful, but because they are healthier, more intelligent, and have better personality traits conducive to higher earnings," Kanazawa explained in a news release.

The data from the National Longitudinal Survey of Adolescent Health also offered narrower categories of relative attractiveness, with less attractive participants split into "very unattractive" and "unattractive."

The differentiation revealed an apparent ugliness premium, with very unattractive people earning more than their merely unattractive peers.

The two researchers published their findings in the Journal of Business and Psychology.