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Ben Nadel at InVision In Real Life (IRL) 2019 (Phoenix, AZ) with: Josh Barber
Ben Nadel at InVision In Real Life (IRL) 2019 (Phoenix, AZ) with: Josh Barber ( @Jorshasaur )

The Science Of Kissing: What Our Lips Are Telling Us By Sheril Kirshenbaum

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As a kid, I thought love was magical; as an adult, I still find love magical, albeit for a more robust set reasons. As science turns its lens on the human brain and continues to investigate the mechanical underpinnings of human emotion, we start to see a universe of complex machinery, feedback loops, hormone cycles, nerve endings, neurotransmitters, sensory perception, and genetic calculations. The Science of Kissing: What Our Lips Are Telling Us, by Sheril Kirshenbaum explores one of the most universal social interactions - the kiss - and looks at how a kiss affects us at the physical level and why kissing is so beneficial for our species.


The Science of Kissing: What Our Lips Are Telling Us by Sheril Kirshenbaum, as reviewed by Ben Nadel.  

Kirshenbaum examines both lips and kissing from an evolutionary, psycho-social, and biological point of view - each of which is equally fascinating. The lips alone are kind of a mind-blowing structure; densely packed with nerve endings, the lips respond intensely to every kind of stimuli which, in turn, triggers a massive response in the brain. In fact, even light stimulation of the lips innervates more of the human brain than genital-sexual stimulation can. As Kirshenbaum aptly puts it:

.... our lips are our most exposed erogenous zone!

With these neural pathways in place, a romantic kiss does nothing less than set off an avalanche of biological activity. During a passionate kiss, our blood vessels dilate; more oxygen is routed to the brain; our breathing quickens and becomes erratic; our cheeks flush; our pulse quickens; our pupils dilate; dopamine, serotonin, norepinephrine, oxytocin, and adrenaline levels spike, leaving our bodies awash in a chemical bath. In short, our biology seem to be hardwired to make kissing extremely pleasurable and, to some degree, addictive.

Oh, and did you know that men who kiss their wives before leaving for work live an average of 5 years longer and earn 20-30 percent more income? Yeah, statistics are awesome!


Any man who can drive safely while kissing a pretty girl is simply not giving the kiss the attention it deserves. -- Albert Einstein  

Of course, the historical and social aspects of kissing are equally interesting. Did you know that there used to be something in Hollywood (1930 - 1968) called the Hayes Code? It stated that:

.... excessive and lustful kissing, lustful embraces, suggestive postures and gestures, are not to be shown unless they were essential to the plot of the movie.

Kissing has not had an easy time of it. In addition to Hollywood - kings, emperors, religions, and even cultures have tried to ban kissing. Of course, none of them were successful; the magic of kissing has, and I'm sure will continue to transcend all obstacles.

One my favorite facts from the book was that Kirshenbaum pointed out that the German language has 30 words for kissing including the term: Nachkussen, which means:

A kiss to make up for those that have not occurred.

That gives me chills. It's got to be one of the most romantic things that I have ever heard. I can only hope to imagine the kind of intense desire that drives that kind of motivation.

Humans are not the only species that kiss. Many other species engage in kissing or "kissing like" behavior such as "necking", touching heads, licking, grooming, and rubbing. In fact, the basic desire to embrace another individual seems to be an almost universal drive in the animal kingdom. And, although this trait is quite commonly shared, the amount of time and effort scientists have put into understanding it is quite limited. Sheril Kirshenbaum provides a very interesting review of the existing information and, as she discusses in her book, is even running some ground-breaking experiments in hopes to examine brain-level responses to kissing and kissing perception.


Since the invention of the kiss, there have only been five kisses that were rated the most passionate, the most pure. This one left them all behind.  

NOTE: Contracts used to be signed with an "X" and then kissed to signify their legality. This is where signing a letter with "xxx" comes from.

Reader Comments


Fascinating. I think this may be worth a read :D

Oh, and did you know that men who kiss their wives before leaving for work live an average of 5 years longer and earn 20-30 percent more income? Yeah, statistics are awesome!

I love this stat.


@Richard - that is because your wife won't nag you as much if you kiss her and tell her you love her frequently.


My wife is away on a trip so we have to keep in touch via phone/VoIP.

I was thinking as I was talking to her that really I just need to record my voice saying, "Yeah?" "Uh-huh," "Honey, I miss you so much," "You're absolutely right," "I don't believe it," and "I love you!" Then, just have my smartphone play those various responses whenever it hears the words, "Y'know?" increases in inflections, (asking a question) and after long pauses.

This way, I can work on earning more money AND live a longer life!

Best. Husband. EVER!


But our ideas are different, like how Ice Ice Baby is different from Under Pressure. It's different, DIFFERENT! ;-)


In fact, even light stimulation of the lips innervates more of the human brain than...

So true! How many of us have not walked outside and been stimilated by a light breeze on our lips? :-)

It's interesting I should read this particular blog article today, because I heard recently about a study done, and it could be the same study, about kissing where the findings were about how important a kiss was to determine long-time compatability for mates, plus, for the whole thing about the continuance of the species. According to the study, when two people kiss, biological information is passed back and forth, and the similation or non stimuilation of the kiss has to do with the chemicals that are passed between the two people interacting and letting the people know on a subconscious level how physically compatible they are in terms of being able to make kids. I wonder how many times in history a kiss has lead to the making of a baby, either instantaneously or over time?

What I inferred from the study and what I heard of it, was that in terms of fertility, some people are just more capable of conceiving with certain people than with others, and when two people kiss, on a subconscious level, the chemicals are passed back and forth, and we are told how compatible you are with this other person in terms of procreation.

Kinda scary, huh? Maybe that means for those of you who don't want kids, you should limit your kissing to those that aren't all that "magical", huh?

I will close my comment with this: I recently, after hearing of the study, got to thinking about kissing...and why we kiss. I just started pondering, I wonder who came up with this idea of two people putting their lips against each others? At one point in history, did some guy just say...hmmm...I think I'll just go and put my lips on that girl's lips, and something good will come out of it. lol. If you think about it, it is kind of unsanitary. Especially with some people! I have had some really bad kissing experiences! With guys who slobbered all over my face. I hate that. And that brought me to consider something else: what if, biologically, a guy is a good match for me, but his technique is terrible and he slobbers all over me like a dog. Will I still, inspite of the horrible technique, biologically have the same experience? hmmmmm...something to think about...


and I'll add this while apologizing for not ending my em tag until the ending, thus italicizing the whole thing (sorry!)...the Hollywood thing makes since. I'd rather not see two people just giving us extraneous kissing the whole movie if it really doesn't do anything to help the plot. For one thing, it may protect women from having men use excuses to hit on them in the movie, etc. For another, maybe it would cut down on broken marriages of the actors, etc., if they would limit it more like they used to. What about Angelina and Brad Pitt in that movie Mr. & Mrs. Smith. Just think...if they had limited those actors and the amount of activity they had on-screen, allowing the two to do actions which "implied" certain things, (like I have seen in older movies), would the two have ever hooked up? And would Brad still be with Jennifer Anniston? Hmmmmm...another thing to ponder...



One thing that I thought about, as far as stimulation, was vibration. If I walk by a speaker that has a lot of base, I can actually feel the vibration from the air on my lips, ever so slightly. They are quite sensitive!

A lot of what you just mentioned was actually discussed in the book, although I didn't really mention it in the review. There are theories way kissing you brings you physically closer together where you can get a good smell of the person and even taste them. While we're not sure, these scents could be interpreted for compatibility. One of the things that Sheril mentioned was immune system markers - that people tend to prefer others with a more diverse set of immune system markers and this would (likely) create offspring with a stronger immune system.

And, as far as the sanitary nature of kissing, that's actually a subtle queue as well - if someone is willing to kiss you, this might be a good sign of one's ability to commit. Of course, the CDC (center for disease control) rates kissing as an extremely low hazard activity; on the other hand, during the time of the Black Plague, many people stopped kissing as I think they believed it was partly responsible for transferring the disease (perhaps due simply to close contact).



I can't say I remember Mr. & Mrs. Smith. I saw it, but from what I recall, it was quite terrible. I think I've blocked most of it out :D


@ Ben lol. Good for you! :-) When you started talking about the immune system, I thought you were saying that kissing someone with a diverse immune system would give YOU better immunity, so that's one of the reason people found it beneficial to kiss, so they could build up their immune system and not get sick as much. When I thought that, before I read the rest of it, the thought going through my mind was...I better get to kissing...NOW...and as many guys as I can (to increase the diversity of my immune system). lol But the I read the rest, so considering the rest, that might not be such a good idea. :-)

About the lips: yes, they are VERY sensitive, and I was being truthful about the wind blowing...however, I think the comparison to the other part may be more for men than women. Or maybe men and some women. Because some women are VERY sensitive in the other part, so I don't think for them the lips are more sensitive. But for men, yes...definitely, and maybe women who are not as sensitive in the other part. I think for men, definitely, because I think men are not as sensitive there. This has partly to do, I believe, with the surgery most men undergo as infants. And with women, I think the range of sensitivity is extreme. This can be infered with the huge success of the toy industry. For women with a lot of sensitivity, those toys don't really do anything, but for women with decreased sensitivity, I guess they really work. I think that's why that industry is so successful...because women like that do exist. I don't imagine anyone buying something and spending money like that on something that doesn't work (they cost SO much!!!)


And here's an anecdote that is kind of funny, I guess, but kind of speaks to the whole thing about whether kissing is sanitary or not. In high school, I was president of the jr. heart board. They had a meeting where they said that AIDS is, although very rare, transmittable by kissing. They said that it was possible in this circumstance: two people are kissing. One has AIDS, one does not. The one who has AIDS happens to be bleeding in the mouth, for whatever reason...maybe he or she bit his or her tongue, gun, or some other reason. The one who does not have AIDS has an ulcer/opening of some sort in his or her mouth. They kiss. The blood is passed to the uninfected person. It enters that person's mouth, and then the sore in his or her mouth. And in that circumstance, the uninfected person could become infected. Ok, I said that it was kind of funny, so here's the funny part: right after I had that meeting, this guy asked me out and wanted to kiss me. I had not been kissed much at all at that point, and wasn't expecting it. The guy kind of just pounced on me and laid it on me. At that point, I proceeded to lecture the guy on the posibility of getting AIDS through kissing and interrogate him on the partners he had had. lol. And I wondered why the guy never asked me out again? lol.

But thanks for sharing the information for the centers for disease control. :-) Useful. And for the record, I'm still cautious, but not quite as jumpy about the whole kissing thing. :-)

I believe in love. I believe in compassion. I believe in human rights. I believe that we can afford to give more of these gifts to the world around us because it costs us nothing to be decent and kind and understanding. And, I want you to know that when you land on this site, you are accepted for who you are, no matter how you identify, what truths you live, or whatever kind of goofy shit makes you feel alive! Rock on with your bad self!
Ben Nadel