Of course men should love women for who they are, au naturel. But there’s a reason why ancient tallow and kohl residues pop up on archaeological digs — makeup draws the attention of men. This is something of a given, but French psychologist Nicolas Gueguen (who also researched men’s unconscious behavior after thinking about love) has found empirical evidence that men — at least on an unconscious level — are more attracted to painted ladies.

Gueguen recruited two women in their early twenties to go to bars for sixty sessions on twenty nights, and sit at a free table near where they were highly visible. The women either wore makeup or not — and when they did, they applied to it to their eyes, cheeks, and lips. Observing the women were members of Gueguen’s research team, who counted the number of men that approached the made-up girls and the minutes lapsed before and between approaches.

The results? Although men approached the women in every session, the come-ons were more frequent when women wore makeup. It took less time for men to make a pass at the women (an average of 17 min vs. 23 min), and more men approached the women per hour (a mean of 2.0 vs 1.5).

What draws guys to lipsticked mouths and darkened eyes? There may be several reasons. As I discuss in BLONDES, makeup simulates high-estrogen qualities that peak at the time of a woman’s cycle when she’s most likely to conceive. Eyes appear wider, lips plumper, features appear more symmetrical. Moreover, made-up women with high-contrast features catch the eye (just as blond hair does). And just as women who dye their hair blonde may appear to desire attention, so do women with makeup. Men might assume, at least subconsciously, that it’s a attention-seeking cue (”look at me!”) — and as a result be more attracted. And it may be a virtuous feedback loop: the more confident a woman feels in her own skin, albeit under a few layers of macquillage, the more attention she seeks — and the more attention she gets.