There’s a biological reason you’re attracted to bad boys

“I should like him, but…”

If you’ve ever uttered this phrase (raises both hands and a foot), particularly when followed by a lamentation of why you prefer this other, decidedly less-great guy instead, it might be time to tune into the ways your hormones are driving your dating decisions.

No, it’s not just teenage boys who try to make mating choices based on “raging” hormones, and the new book Hormonal deep dives into how we can better understand our behaviors (romantic and otherwise) once we know how our hormones may be influencing them.

Research has shown, for example, that women are more interested in a specific type of man—what you might call an alpha—during ovulation than we are at other points in our monthly cycle. “There’s a suite of sexually attractive qualities,” like symmetrical faces and dominant behaviors, author Martie Haselton, PhD, tells me, “that women prefer more during their fertile days.”

This supports the “good genes” theory of mate selection, which suggests that women (and female animals) are drawn to “males with traits associated with fit genes that they can pass on to their offspring,” Dr. Haselton explains in the book. She calls this type of guy “Sexy Cad.” He’s sexy for obvious reasons; he’s a cad (see also: player) because his rarity—not everyone can be alpha, after all—puts him in high demand. With such an abundance of options, why would he settle down?

“Given the high demand for alpha males with a sweet and caring side, it seems that women learned…to exchange sexy for stable.”

The other three weeks of the month, Dr. Haselton says, women are much better judges of character: We’re attracted to men we deem caring, responsible, and nurturing. And in the long run, this desire to find a partner who will likely make a good father usually wins out—even though we may still desire, say, Colin Farrell when we’re most fertile. “Given the high demand for alpha males with a sweet and caring side, it seems that women learned…to exchange sexy for stable, picking the reliable male who would help at the nest,” Dr. Haselton says. This choice, then, has less to do with hormones than it does with availability. (Romantic, right?)

But it is a choice, one that we can better control once we understand its driving forces, Dr. Haselton believes. And in this way, hormone education is a tool for female empowerment. “We can say, ‘I know this [desire] was designed to help ancestral females solve certain kinds of problems that don’t afflict me in the modern environment, so I can ignore it,” she explains.

Hormone education is a tool for female empowerment.

What’s more, Dr. Haselton says, attempting to avoid talk of the hormonal differences between men and women can be detrimental to the cause of women’s health. “We don’t know enough about women and their hormones,” she says. “There are a lot of topics that need to be studied more”—[e.g. the consequences of using the contraceptive pill, whether or not we should do hormone replacement therapy, what happens in the postpartum period and how we can help women better adjust, etc.]—”and some of them, I think, have been avoided because people were concerned about the [negative] ‘hormonal’ stereotype.” You know the one: Where a “hormonal” woman is a crying, yelling, ice-cream-eating mess.

Given that I live in Los Angeles, where the dating market certainly seems to favor male choice, I most certainly find the knowledge that I’m actually the one being selective empowering. The next time a bad boy calls, I’ll know I’m choosing him for the biological cues his good looks and dominant behaviors offer and, as it turns out, not much else of substance. Meanwhile, that good guy I should like? Well, it looks like my intuition is right: I really should give him a chance.

If you, like me, find this topic fascinating, Well+Good council member Alissa Vitti has deets on how tracking your cycle can actually help you manifest your dreams—for real. Plus, here’s info on how to better balance your hormones using diet.