OK! Normally, I ignore most of what evolutionary psychology has to say because they are utter pan-adaptationists. Some have even used this proclivity to “rationalize” rape and other seriously fucked up behaviors. However, I couldn’t let this one go...
Or: Why Swallowers are Happier
Most of my female readers are probably familiar with the McClintock effect, also known as the “dormitory effect.” It’s the discovery of the phenomenon wherein the menstrual cycles of women living in close quarters tend to synchronize. This phenomenon has been observed in women living together. It has been found in roommates, close friends, and most strongly between mothers and daughters. It has also been noted in mice, hamsters, and rats. It has been suggested that ovulation (the process of releasing an egg from the ovary) is socially regulated and this leads to what is called menstrual synchronicity. In other words, women who live together will have their periods at the same time (there's even a FB page dedicated to this effect).
A couple of researchers developed an interest in the psychological properties of semen as a result in their exploration of menstrual synchrony. Gordon Gallup and Rebecca Burch, evolutionary psychologists from the State University of New York, had stumbled onto data showing that, unlike heterosexually active women residing together, sexually involved lesbians failed to show evidence of the “McClintock effect.” Since olfactory signals (called pheromones) are known to mediate menstrual synchrony, the authors found this peculiar.
They wanted to know what it was about heterosexual females that promoted menstrual synchrony, or conversely what is it about lesbians that prevented menstrual synchrony. It occurred to them that one feature that distinguishes heterosexual women from lesbians is the presence or absence of semen in the female reproductive tract. Lesbians have semen-free sex.
Gallup and Burch hypothesized that chemicals in human semen affect female biology in such a way that women who have condomless sex literally start to smell different from those women who do not -- or at least, their bodies emit the pheromones that neurologically imprint menstrual cycles among cohabitating women. Gallup and Burch quickly discovered that although much was known about basic semen chemistry, virtually nothing was known about how these chemicals might influence female biology, behavior, and psychology.
It has been known for a very long time that the vagina is an ideal route for drug delivery. An impressive vascular network surrounds the vagina: arteries, blood vessels, and lymphatic vessels abound, and -- unlike some other routes of drug administration -- chemicals that are absorbed through the vaginal walls have an almost direct line to the body’s circulatory system. Taking this into consideration, Gallup and Burch surmised that, as with any artificially derived chemical substance, semen might also have certain chemical properties that affect female biology.
Bear in mind that although they are often erroneously mistaken in everyday language, “semen” is not the same thing as “sperm.” In fact, only about 1 to 5 percent of the average human ejaculate consists of sperm cells. The rest of the ejaculate is referred to as “seminal plasma.” So in discussing the chemical composition of semen, it is the plasma itself, not the spermatozoa, that is at issue.
It turns out that, in fact, that semen has a very complicated chemical profile, containing over 50 different compounds (including hormones, neurotransmitters, endorphins, and immunosupressants) each with a special function and occurring in different concentrations within the seminal plasma. The most conspicuous of these compounds is the bundle of mood-enhancing chemicals in semen. There is much good in my jism, it seems. These include, but are by no means limited to, cortisol (known to increase affection), estrone (which elevates mood), prolactin (a natural antidepressant), oxytocin (also known as the “love chemical” which elevates mood), thyrotropin-releasing hormone (another antidepressant), melatonin (a sleep-inducing agent) and even serotonin (perhaps the most well-known antidepressant neurotransmitter).
Given the composition of semen, and this is just a small sample of the mind-altering drugs found in human semen, Gallup and Burch, along with psychologist Steven Platek, hypothesized that women having unprotected sex should be less depressed than suitable control participants. To investigate whether semen has antidepressant effects, the authors rounded up 293 college females from the SUNY-Albany campus, who agreed to fill out an anonymous, written questionnaire about various aspects of their sexual behavior. Recent sexual activity without condoms was used as an indirect measure of seminal plasma circulating in the woman’s body. Each participant also completed the Beck Depression Inventory, a commonly used clinical measure of depressive symptoms.
Now, I think you know where I’m going with this, right? LOL
The most significant findings from this 2002 study was that sexually active (non-condom-using) women also showed fewer depressive symptoms than did those who abstained from sex altogether. By contrast, sexually active women, even really promiscuous ones, who used condoms were just as depressed as those practicing total abstinence. In other words, it’s not just that women who are having sex are simply happier, but instead happiness appears to be a function of the ambient seminal fluid pulsing through one’s veins.
My ding dong, dear ladies, is a happiness drug dispenser! LOL I’m kidding! Let me add that similar studies looking into oral and anal sex (heterosexual and homosexual) resulted in similar findings. This lends credence to my assertion that “spitters are quitters.” Sorry, I just can’t help myself, the jokes write themselves here. LOL
So! What do we get from all this (aside from the realization that you can call me for some serotonin uptake)? Well, that in addition to suffering some muscle atrophy you might also experience some depressive episodes if you’re not getting your fair measure of semen. Don’t you just love it?!! Actually, the study is plagued by a number of methodological issues, but I had to grab onto it. LOL I also am not suggesting depression isn't a serious issue, I'm just having a little fun. One highly respected surgeon, however, lost his job for making similar jokes.
Well, that’s it for today, boys and girls! Remember: sex is good for you!
My name is Eddie and I’m in recovery from civilization…
Bering, J. (2010 September 22). An ode to the many evolved virtues of human semen. Scientific American, 31, 289-293. (here)
Gallup, G. G., Jr., Burch, R. L., & Platek, S. M. (2002). Does Semen Have Antidepressant Properties? Archives of Sexual Behavior, 31(3), 289-293. (here)