Beauty Treatment: Pretty Powerful

The moment you lay eyes on a hottie with a svelte, sexy figure or dreamy eyes, you're intrigued. What's more, recent research shows that the Adonis before you can actually change your behavior. Here's what beauty can do.—Sarah Henrich

• Launch a Thousand Ships

  Helen of Troy was just the beginning. Men who view images of attractive women are more likely to endorse pro-war statements and to respond to images and words relating to war—but don't show increased general aggression, a study from the Chinese University of Hong Kong reports. Battle thins the competition: "There are far more sperms than eggs, meaning some men must be eliminated from the mating game," says researcher Lei Chang. "This leads to male-to-male combat." A pretty woman ignites those primal desires.

• Get Its Money Back

  Healthy-looking people are more likely than sickly ones to be repaid if they perform a favor or lend money, new research in Evolution and Human Behavior notes. We want to curry favor with someone who will live longer and make it worthwhile, and a pretty face indicates heartiness. Men are likeliest to return a beautiful woman's favor: "Guys think they might get something out of a woman who's already been nice to them," says Daniel Brian Krupp of McMaster University. Women (who are less driven by sexual opportunities) don't discriminate by sex, but still favor a foxy face.

• Make Women Want It All

  Gorgeous take-charge females shift our views of what a woman should be, according to research from UC at Davis. Subjects viewed movie clips where the female protagonists were attractive (Angelina Jolie) or less attractive (Kathy Bates) in both aggressive and nonaggressive roles. Of the four heroines, Jolie's Tomb Raider character—both hot and aggressive—was judged by both genders to be the best role model. "We're asking women to be Lara Croft—brilliant, kick-ass, super-model-like—and that's a harsh comparison," worries study author Laramie Taylor.

• Open a Window to the Soul

  When you meet a hottie, not only do you assume he has a glowing personality—you also accurately discern his relative character strengths, University of British Columbia scientists say. Subjects chatted with strangers, then rated their looks and attributes. The people whom a participant deemed cutest were also those whose intangible traits—such as conscientiousness—he or she could best predict. When we find someone appealing, we notice subtle character cues. "We judge a book by its cover," says researcher Jeremy Biesanz, "but when it's beautiful, we read it more closely."

Body Boomerang

When college-age women viewed magazines stocked with images of thin models for five days straight, something strange happened: The readers' body image improved. But those whose satisfaction improved the most were also more likely to have started dieting during the study.

It may be that these women feel inspired and momentarily hopeful when they see the pictures, especially paired with diet tips, says Ohio State researcher Silvia Knobloch-Westerwick—but their confidence may plummet when their fantasy bodies seem less attainable again. What's more, she notes, "these images likely contribute to women's obsession with weight, instead of more important issues, such as their health and career."—Nancy Ryerson