facts on attraction

Photo: Marianne Haas

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Love—or Something—Was in the Air
When women breathe in androstadienone, an often-odorless testosterone derivative in male sweat, they give men higher attractiveness ratings than they would otherwise. After about 15 minutes of exposure, the chemical makes a woman subtly more attentive, aroused—and even happier— with effects continuing for up to an hour, finds a study led by Claire Wyart at the University of California at Berkeley. (In case you're wondering, men vary in their androstadienone levels—and, no, the chemical doesn't brainwash women into having sex or falling in love. It's much more subtle than that.)