INVESTIGATIVE FICTION Kissingâ€™s Chemical Counterparts April 13, 2013 Written by Colby Stream Edited by Nicholas Chimonas
Kissing’s Chemical Counterparts If you haven’t read the first part of this series yet, I suggest you do so. It traces the history and evolution of kissing from ancient Eastern and Western cultures, through the colonization of America and into the modern day. In this section we’ll look at two different chemicals that interact during kissing: oxytocin and dopamine. Additionally, we’ll discuss the role of testosterone and, finally, look at the health benefits that scientists have associated with kissing and the release of these chemicals.
Oxytocin Kissing releases a chemical called oxytocin (pronounced oxy-toe-sin). Although the pituitary gland produces oxytocin (and it’s the gland people generally know most about), it’s not the only gland that produces the chemical. We know this because oxytocin released from the pituitary gland can’t re-enter the brain (it’s stopped by the blood-brain barrier). In order for oxytocin to reach the oxytocin receptors in the brain, then, it must be released within the brain itself. News articles and scientists often refer to oxytocin as the bonding chemical. When it’s released in your body you’re more likely to bond with whomever you are with, feeling more trust and attachment toward them. In fact, oxytocin even plays an important role in the birthing and feeding process. Mothers release oxytocin into their milk, creating and reinforcing the bond between mother and child. This is an important concept to note: oxytocin is not just released during kissing. Everyday activities that also trigger the release of oxytocin include: • • • • •
Handshakes Hugging Cuddling Sex and orgasm Even watching an emotional movie
Why do these actions produce the chemical? That’s a little like asking why your body produces adrenaline in certain situations; it’s just the way our bodies work. If I had to give a more definitive answer, though, I’d guess that oxytocin is inextricably linked to
our humanity. Science suggests that humans crave touch, even need it to survive; oxytocin seems to be a key component to a person’s need for physical touch.
Other Oxytocin Effects Oxytocin produces a “faithfulness” effect in men. In one study several men (both married and single) were given oxytocin via a nasal spray. Scientists hypothesized that when approached by an attractive woman these men (married or not) would be drawn toward her. What they found out, however, is that married men became uncomfortable by the physical distance of the woman 4-6 inches farther away than single men. You can read the specifics on this study if you want to know more. This makes me wonder, “If two people kiss more often, does that make them more likely to be faithful to each other?” Unfortunately, the answer to that question remains inconclusive. Even though it’s unfounded, however, it’s still a darn good reason to engage in kissing (and cuddling, and hugging, and sex) more often. Oxytocin is only a small part of the overall chemical process. I believe – and I’ll show below – that oxytocin becomes even more effective when coupled with the release of dopamine.
Dopamine Dopamine is what scientists call a “neurotransmitter.” This means that dopamine helps the brain pass signals from one neuron to another across synapses. (A synapse – not to be confused with a synapsis – is a tiny gap between two nerve cells.) Like oxytocin, dopamine cannot cross the blood-brain barrier and thus is produced in several areas of the brain. One of these is the area associated with pleasure and motivation. Because of this, when your brain releases dopamine you feel pleasure. Kissing itself does not release dopamine. In fact, you may be thinking to yourself, “My partner and I kiss a lot, but we don’t have that sense of passion we used to have.” Dopamine is released when we do something that we perceive as new and exciting. In other words, our brain rewards us for doing something novel. Thus, a kiss before bed may not produce any dopamine while a kiss at the top of a Ferris Wheel or Roller Coaster might (if it’s your first time). Think back to the first kiss you ever had (or ever had with your current partner). You’ll remember a rush and a sense of excitement and pleasure. That was dopamine. I mentioned above that oxytocin and dopamine work together. They do, but not directly. The chemicals never physically mix within the brain. Instead, they create a synergistic effect. When you kiss, oxytocin makes you feel attached to and secure around whomever you’re kissing. If the kiss also triggers dopamine then your body rewards not just the kiss
but also the sense of trust and attachment you feel toward the other person, drawing you even closer together. Keep in mind that, so far, we haven’t discussed anything exclusive to kissing. You could be holding hands with someone while trying something new and, conceivable, experience the same effect. A quick note before we move on: This does not mean that kissing any new person will produce dopamine. In a way that scientists still can’t quite comprehend, these chemicals are part of a complex system to help us choose a partner. If you kiss someone and nothing really happens, it’s your body’s way of saying “the chemistry just isn’t there.” Whereas some might argue that you should live and even sleep together before choosing a partner, the body appears to be way ahead of us; kissing is the original mate selection and assessment tool. If you disagreed with the previous statement, you’re not alone. My editor, Nick, pointed out that the “original mate selection and assessment tool” would also be the most primitive. The argument goes that since animals don’t choose mates by kissing – but through chance, sexual cycle and sexual intercourse – kissing isn’t the most primitive action but, instead, the more advanced one. I see the logic in this argument, but I’m not sure I agree. Can you call the way my dog reproduces “choosing a mate,” especially when compared to my marriage? I’m simply not willing to make the call, so I’ve presented both arguments here. Could I have deleted my first assertion? Certainly, but where’s the fun in that? All in all, kissing is one tool that helps us select and assess a mate.
Testosterone and Saliva Saliva has trace amounts of testosterone. Before we jump into the effects of testosterone, however, lets get on the same page about what it is. Testosterone is produced mainly in the testicles. It has a lot of jobs in the male body, from producing sperm to helping with bone density and fat distribution. And, yes, it contributes to sexual drive. As you may know, the female body produces testosterone as well, but when men and women kiss and swap saliva women may also pick up some extra testosterone in the process. (Read the second paragraph here if you want studies backing this paragraph up.) This means that kissing – or, rather, the transmission of testosterone – acts as a natural primer for sex. Keep in mind, though, that testosterone isn’t the only factor. Saliva goes both ways. Scientists believe that men unconsciously use a woman’s saliva to monitor her fertility and estrogen cycle.
Just how potent is testosterone in saliva? How easily can a man monitor a woman’s fertility and estrogen cycle via her saliva? There’s really no way to tell, but they are likely some of the intricacies we talked about above that contribute to whether a couple finds “chemistry” or not.
Other Considerations in Kissing Our bodies send signals that we are often unconscious of. One attribute specific to kissing (instead of just general touch, such as hand holding) is proximity. When you’re close to a person for an extended period of time your body picks up a number of signals. These might include: • • • • • •
Smell Hormones (that you can’t smell) Body temperature Breath Noises and sounds Sight (both how the person is dressed and things you may not have seen up close)
All of these tiny signals add up to one big message. How the body interprets them is more complex than I (and perhaps anyone) can explain, but it’s worth noting that the small things matter.
Health Benefits Kissing contributes to our everyday health. In addition to connecting us to another human being and rewarding us for trying something new and exciting, it lowers cortisol levels (the chemical associated with stress). But there’s more to it than that. In 2009 scientists set out to test what kind of other health benefits kissing could produce. They found that: • • • •
Kissing can improve your immune system, better protecting you against allergens; Kissing not only lowers your current stress levels but can protect you against becoming stressed as easily in the future; In fact, when kissing you exchange a chemical through your skin called “sebum,” which helps your body relax and stay relaxed; Because of these effects, you may see a decrease in your cholesterol levels.
If you’re interested, you can read more about the study and the health benefits of kissing. Given what we’ve learned in this and the last section, what does it mean? How can we use this information to better our lives and our children’s lives? That will be the subject of the third and final study. I’ll give my thoughts about how I think we can respond, and if you have something I don’t talk about I’ll open up the comments section for you to add your own two cents.
*Smooch* and a flood of chemicals. But which chemicals? You could search the internet, but you've already found the only comprehensive artic...