Are parasites making me sexy?


She's got parasites, and she knows how to use them. ©Charlie Nucci/Corbis

Let's face it, ladies: If at all possible, you'd like to have it going on this weekend. Yet as effortless as some gals make it look, there's an art to being sexy. Sometimes that carefree smile requires the inner confidence that only a trip to Victoria Secret's can offer. Other times it's a matter of applying several coats of cosmetics and slipping into that special skirt.

But what if there was a way to spice things up that didn't involve manicures and vodka tonics? Yep, you could be just one parasite away from hitting the town in style.

Club it Up With Toxoplasma Gondii

Scientists have known about the parasite toxoplasma gondii for quite a while, and it's been running wild in our bodies for ages. Between 30 and 60 percent of the global population is infected! For the longest, we thought the microscopic creature was only a risk to pregnant or immunodeficient individuals, but studies in recent years have stirred a number of concerns on Toxoplasma's possible psychiatric effects.

Nevertheless, here's some good news: The parasites might just be flipping the sexy switch in the female brain. A 2006 Australian study found that Toxoplasma-infected women typically had more sex appeal to the opposite sex. Compared to uninfected control groups, they were friendlier, more outgoing and more promiscuous.

Of course, the Toxoplasma really just want you to behave recklessly enough to be eaten by a lion, as only feline hosts allow them to continue their life cycle. And hey, if it takes you dancing all night and sleeping with that guy in the Navy uniform, then that's what has to happen!

It's Not You, It's My Parasites

And speaking of going home with the guy in the Navy uniform, you're probably better off if he doesn't have a population of Toxoplasma inside his body as well. The same study that reported increased sexiness in female hosts reported a decidedly less attractive trend in males: lower IQs, short attention spans, risky behavior, anti-social attitudes, jealousy and a generally gloomy disposition. As you might imagine, they were also less attractive to women.

Other studies back up a number of these findings regarding long-term personality changes due to Toxoplasma infection. While sexiness and promiscuity don't always pop up among the females, intelligence, affection and social activity tend to remain a key feature -- sometimes alongside loyalty and frugality.

The men continue to come across as risk-taking dolts in these studies, with the unsettling compromise that both infected sexes may wind up more prone to feelings of guilt, self-doubt and insecurity. Remind you of any couples you know?

Just be Yourself

With all of this, it's important to understand that our knowledge of Toxoplasma is still evolving. Plus, with any study, there's always the problem of causality and correlation. Does this parasite make ladies more sexy or are sexy ladies just more likely to be infected?

Either way, the last thing you want to do is intentionally ingest parasites from a cat's belly on the off chance that it will make you look hotter Saturday night. The largest sexual organ, after all, is the human brain. Try not to let any pesky protozoan mess around with it.

Originally published at Animal Planet. Special thanks to editor Katherine Neer, who threw in lots of "Sex and the City" stuff.


About the Author: Robert Lamb spent his childhood reading books and staring into the woods — first in Newfoundland, Canada and then in rural Tennessee. There was also a long stretch in which he was terrified of alien abduction. He earned a degree in creative writing. He taught high school and then attended journalism school. He wrote for the smallest of small-town newspapers before finally becoming a full-time science writer and podcaster. He’s currently a senior writer at HowStuffWorks and has co-hosted the science podcast Stuff to Blow Your Mind since its inception in 2010. In his spare time, he enjoys traveling with his wife Bonnie, discussing dinosaurs with his son Bastian and crafting the occasional work of fiction.