You kiss. I kiss. We all kiss!!!
If I were to ask a kid what do they think kissing is, they would have said that kissing is when two people touch lips.
But if I had to think about it, kissing is a bit gross isn’t? I’m swapping my saliva with another person. I don’t know if they brush their teeth regularly nor do I know if they are carrying any disease.
In fact, there was even a very rare case of potential infection of hepatitis B virus from kissing! If there are so many risks from kissing, why do we kiss?
Evolutionary psychologists have argued that what we know today as kissing may have come from kiss-feeding (premastication), the exchange of pre-chewed food from one mouth to another. Even I still remembered as a young child, my mother feed chewed food from her mouth to me. Curious by this affectionate action, I recently discovered that kiss-feeding (and other behaviours such as embracing) were derived from maternal bonding, in the book “Indoctrinability, ideology, and warfare: Evolutionary perspectives”.
So, mouth to mouth attachment has a history of intimacy, trust and closeness between a mother and child. But what does science have to say about it?
Well, there is actually a science dedicated to kissing, which called Philematology (Philos in ancient Greek = earthy love). Very sexy isn’t?
What they found is that kissing can burn calories, somewhere between 2 to 26 calories per minute of kissing, while releasing epinephrine and norepinephrine in the blood, making your heart pump faster.
Your saliva also carries information about who you are and maybe even your level of health. A paper in the American Journal of Medicine said that when we kiss, there is approximately 9 ml of water, 0.7 of protein, 0,18 mg of organic compounds, 0.71 mg of different fats and 0.45 mg of sodium chloride.
There are many advantages to swapping nutrient-rich saliva.
In maternal bonding that I mentioned above, a type of kissing called kiss-feeding can complement breastfeeding and improving infants’ health. It provides significant amounts of carbohydrates, proteins and nutrients that are not always available through breast milk and transfer micronutrients such as iron, zinc and vitamin B12 to the infants.
More importantly, as adults, I think we kiss because it feels good. Our lips and tongue have many nerve ending, making it very sensitive.
A good kiss can also a biological evidence that your kisser might be a good mate.
In a 2013 paper published by Wlodarski and his team, they found that women tended to priorities a partner’s ability to kiss more than men did, in a heterosexual context. This is because women used the first kiss to assess whether this partner is suitable for a relationship. A 2014 study also found that some people are more attractive for short-term relationships because of their ability to be a good kisser.
Another theory is that the mucous membranes in our mouth are permeable to hormones like testosterone, making kissing a way to sample a potential mate. Even though this argument is a little hard to prove in human interaction, it would still add to our knowledge about human attraction and mating behaviour.
However, I think we can conclude that the study of kissing is always going to be an imperfect science because everyone is different. We came from different origin and had mixed views about kissing.
Now, go forth and kiss someone today.
Be it your lover, family member or a stranger, because we all love each other.