A fiery debate about female has surfaced, between self-proclaimed "sluts" and those who believe that casual sex is inherently unhealthy and destructive towards women. On the one side are blogger Jaclyn Friedman and her sisterhood of sexually empowered women, and on the other side are bloggers like Susan Walsh, who argue that women who treat sex casually are setting themselves up for heartache and worse.

A part of the argument concerns whether women, by virtue of the way neurochemicals work in the female brain, are just not biologically set up to have casual sex. Helen Fisher said something like this, when she pointed out that we (or women at least) should be prepared to fall in love with people we have sex with. It's kinda like smiling - if I take a sad person, and have them smile, it activates parts of their brain that are active when we're happy (and smiling). After a few moments of smiling, a sad person will report feeling happier. This neurochemical argument works similarly, suggesting that the female brain reacts with bonding, and love after sex, in a way that makes casual sex decidedly less than casual. But, this is a determinist argument, suggesting that "biology is destiny," in a way that the feminist movement has rejected for decades.

The health or dangers of casual sex is itself a hotly debated issue. Swedish researchers Langstrom and Hanson (2006) surveyed a random sample of 2500 Swedish residents, and found that people with high rates of "impersonal sex" tended to have poorer relationships, more problems, relationship problems and were generally dissatisfied with life. But, we don't know which way causality goes, and which comes first, the chicken or egg? Were these people having more problems because they were having more one-night stands, or were they having more anonymous sex, because they were having more problems? And it's noteworthy that their results didn't support the notion that impersonal sex itself is detrimental, just high rates of it. In other words, if you're just having casual sex or anonymous sex every now and then, it may not be harmful.

Does hooking up result in the kind of risk and emotional harm that we , and that people like Walsh tell us we should avoid? Well, sort of. In some cases. The most thorough study of this phenomenon was done by Owen et al, in 2008, where he and other researchers assessed over 800 college students, on campuses in the western and southeastern United States. Results were fascinating.

Owen's research found that there was no difference between the numbers of men and women who reported hooking up. Results found that those college students who were hooking up were not dysfunctional, disturbed, emotionally-troubled young adults. They tended to be from wealthier families, and in men at least, higher psychological "well-being" predicted more hooking up (this might relate to mate selection, in that women might be more likely to hook-up with a man who is doing well). More men reported that the experiences of hooking up was positive (around 50%), compared to 24% of women. Almost half of all women reported a negative reaction to hooking up. People who viewed hooking up positively were more likely to have positive experiences with hooking up. If you believe it will be a good experience, or a bad experience, it seems that this becomes a self-fulfilling prophecy. So, if we are telling women that casual sex is negative and unfulfilling, it may be that we are creating this outcome in women, who might otherwise be unbothered by just hooking up.

A recently published article on the Electronic Journal of Human Sexuality examines the issue of casual, or recreational sex, and finds that for both men and women, casual sex improves their feelings of sexual satisfaction. But, for men and not for women, recreational sex improves their overall feelings of and sexual .

Do men and women differ in their responses to casual sex? Yes. Do we understand these differences fully, or their causes? No. Are the differences universal and categorical? No. All men do not enjoy casual sex, though this might be true for many of them. Nor are all women harmed by casual sex, or turned off by it, though again, this might be true for many women.

I find it interesting that this is a debate between women. Frankly, most men could care less. Or, to paraphrase the wonderful Mae West, most men love women with a promiscuous past. They hope history will repeat itself. Most of the negative social consequences women experience for sexual behaviors come from women. A wonderful 2002 article by Roy Baumeister and Jean Twenge (in the Review of General Psychology) suggests that women more frequently work to suppress other women's sexual behaviors, far more than men do. Research with females and sexuality offers numerous examples, many gathered by Baumeister and Twenge, showing the degree to which females suppress and limit the sexuality of other females (note, this isn't necessarily a bad thing, but just the way it is-often, in the examples below, there are real risks these females are trying to protect other women from):

• When males go on spring break, they often agree to help each other "get laid." When women go on spring break, they much more often set up arrangements to get each other out of sexual situations and prevent each other from going "too far."

• The degree of close communication between mother and daughter predicts the daughters' sexual activity-the more communication, the less the daughter is sexually active. Degree of communication with father has no impact on the daughters' sexual activity.

• In female friendships, the sexual activity level of one friend tends to be consistent with the rate of the other female. Contrary to many assumptions, when a girl begins to have sexual activity or loses her virginity, they don't usually "drop" their friends that aren't having sex, taking up with girls who are. This is because once one girl begins to have sex, it increases the likelihood that her friends will soon follow.

• The "double standard," that some sexual activities are okay for males, but not females, is far more supported by women than men.

• Gossip by other women, and the reputation one holds among other women, are often cited as the most powerful influences on women to "hold back sexually."

• Highly sexual women (those who report wanting sex at least seven times a week or more) report that they typically have much better relationships with men, including just , and relatively poor friendships with women. Men are more accepting of these highly sexual women, and far less judgmental.

Can women enjoy casual sex? Certainly. Without a doubt. Beautician Nikki Lee boasts in the British Daily Mail that she's had sex with over five thousand men, and loved every minute of it. It makes her feel sexy and proud, and if it's evidence of an illness, she's clear that it's one she doesn't want to be cured of. But SHOULD women (or men) have casual sex? That's a different question and one that is not likely to be answered clearly or universally by science. Even Langstrom and Hughes' research showed that it may only be unhealthy in excess. And other research suggests that it is more about your preconceptions and moral beliefs than about even the neurochemistry involved.

Ultimately, I like the answer by the "Sex Academic" who says that women should be supporting each other to make their own decisions, rather than making their decisions for them. If a woman wants to be a self-proclaimed slut, while another woman wants to wait till , women should equally support both of them to have the right to make their own sexual decisions.