Research scientist Sheril Kirshenbaum spoke Thursday at Louisville, Kentucky's four-day IdeaFestival, a gathering assembled to promote innovation and creative thinking. Discussing her book, The Science of Kissing, Kirshenbaum said, "There really is a chemical basis for falling in love. I don't think trying to understand it takes any of the romance out of the equation," and "A first kiss is nature's ultimate litmus test."

In her book, Kirshenbaum writes about the way men and women make different value judgments about the art of kissing. Women may see it as a compatibility gauge, while it may be viewed as more of a "means to an end" by men. And since men's saliva is packed with testosterone, which raises a woman's libido (see Jane Fonda), literally swapping spit is a good way to prime the pump, so to speak. For men, it's "a way to legally slip her a natural sex stimulant." 

Kissing, as we know, is also healing, activating that sweet sweet dopamine. And oxytocin, which engenders feelings of attachment, is like a hit of natural ecstasy. Randy humans will smell each other at close range to detect a group of genes known as the major histocompatibility complex (MHC), which basically controls the efficacy of our immune systems. Greater diversity of MHC indicates healthier immune systems in future offspring. So women will sniff out a man who can provide her future babies with genetic benefits. Olivia Manning (Peyton and Eli's mom) must have some smeller. 

Commentarium (22 Comments)

Sep 23 11 - 2:08pm

Isn't this the bullshit pseudo-science you people make fun of in "horrible tips for a miserable sex life?"

Sep 23 11 - 3:36pm

What? This isn't bullshit pseudo-science in the least. As a biology student this is something we learn about in class, and it's certainly well-researched. Male saliva contains good amounts of testosterone, which will be passed to the person they're kissing. That's it, very straight forward.

Sep 24 11 - 1:06pm

No, LM. It's legit. But congratulations to you for not being able to tell the difference.

Nov 11 11 - 11:58pm

It's true. There's a huge bulk of current peer-reviewed literature about MHC and testosterone in saliva. It's pretty much intro-level biology class material.

Sep 23 11 - 3:40pm
Mr. Man

Ah, sweet sweet dopamine.

Sep 23 11 - 3:48pm

Wow, Jeff, thanks for that "Most disturbing kisses" video. I was about to eat this sandwich and now I can't

Sep 23 11 - 5:01pm

Just like I couldn't eat my dinner after watching Carley's mom last night.

Sep 23 11 - 4:06pm

No issue with the science but the central assertion that men lead with the wet/sloppy is a bit of a leap, unless your experience of kissing is confined to viewing porn. If dopamine's the kick, isn't it just as likely that women are reaching into the honey jar for a hit - not being spoon fed?

Sep 23 11 - 7:05pm

Or is it possible that we all want to get our ya-yas?
Still, your point is well taken.

Sep 23 11 - 8:23pm

I dated an excitable girl for a while who would run up, jump and lock her legs around my waist and near eat me.

She must have been a dopamine junky. I finally got rid of her by eating copious amounts of garlic to get her tongue out of my tonsils, long enough to breathe.
Maybe she was a vampire.

Sep 24 11 - 1:33am

Hmm, I'm female and I'm always accused of giving my husband sloppy kisses. I think my youngest daughter has learned from me too.

Sep 24 11 - 8:55am
Sexual Harras. Panda

Your youngest learnt to give your hubby/her dad wet sloppy kisses, from you? Way TMI.

Sep 24 11 - 9:48am

this is obvious, they are hoping the kiss will lead to them getting it on and then slogging at

Sep 25 11 - 5:05am

I have always found kissing kind of disgusting.

Sep 25 11 - 9:10pm

I'm gonna go ask my boyfriend to spit in my mouth

Sep 27 11 - 1:14am

That is kind of weird, just so you know... If my girlfriend asked me to spit in her mouth, I might have to end our relationship. Sloppy kissing is one thing...but spitting brings things to a completely different level. lol

Sep 25 11 - 9:38pm

Is Al Gore is kissing Rip Taylor?

Sep 28 11 - 2:42pm

That's the younger, less bloated version of Al Gore around 2000. And he is kissing his former wife Tipper, who seemed to be more attracted to pre-Global Warming, more relevant vice-president Al Gore.

Sep 30 11 - 12:15am

Someone wants to fuck me, boys cal me +918056116537

Oct 06 11 - 4:40pm
Patrick Pete

My girl-friend,once spat in my mouth,while we kissed.I knew She did that ,just to entice and impress,me,or to be called,lovely girl!How i wished,she knew how disgusting it was!In the long-run,the relationship ,headed for the ROCK,because of that.Couldn't i've fired the relationship ?

Nov 11 11 - 11:56pm
correct punctuation

I exist to make your strange comments intelligible! Please, don't be a stranger!

Jan 13 12 - 6:52pm

My current boyfriend tends to give me really sloppy kisses and I often find my lips glistening with his saliva. His mouth & lips are quite big, well, bigger than mine so I guess that's expected. I didn't like it at first because I wasn't used to his style and there was only one guy I enjoyed kissing before I dated my boyfriend.