4 Scientific Reasons Humans Kiss – Just in Time for Valentine’s Day

It may seem like kissing is just what loved ones do, but researchers have actually found proof that the instinct to lock lips goes much deeper. Four main themes popped out from various studies, indicating just how involved our bodies and genetics have attributed to the evolution of kissing in most of the world’s cultures.


#1 – That Feel-Good Boost
When it comes to romantic kisses, new relationships often speak of a head rush or crazy exciting feeling. Usually people can retain 90% of the details of their first kiss. This is due to the three part hormone mixture it stirs up in our brains, and the fact that other functions in our body black out to focus on the smooch. The head-in-the-clouds feeling of a deep, romantic kiss come from combining dopamine, serotonin, and oxytocin. The pleasure spot of our brain lights up. It stimulates our underlying addictive nature, euphoric feelings, and also the parts of our mind that attach an experience with affection and relational complexities.


#2 – Establishing Respect and Affection
Although establishing respect and affection aren’t necessarily the main objectives when one person kisses another, it is subtly relevant within both culture and instinct. Friends and family members kiss each other upon arrival for a visit, saying good-bye, at bed time, in greeting, and in concern during hard times to comfort and encourage. In some cultures, students or the young ones in families are expected to kiss the hand or face of an elderly relative or master as a sign of thanks for their wisdom.


#3 – Choosing a Mate and Continuing the Human Race
Of course, those passionate make-out sessions in any relationship do work up the body in preparation for intercourse. Believe it or not, that’s part of our genetic programing. The MHC (major histocompatibility complex) that messes with our immune system and pheromones has been proven to literally make opposites attract. By making a man and woman enjoy the scent of someone with different MHC genes, their offspring would have a stronger immune system that’s better able to handle all the germs and diseases thrown at them when they arrive. Kissing literally brings us close enough for our systems to check out how compatible our genes are. After all, nature needs the human race to continue.
According to the University of Oxford, a companion paper in Human Nature reported that a women’s specific time in the menstrual cycle also determined how their attitudes toward kissing is. Young relationship kissing seemed more important when they were in the stage of their cycle in which they could most easily get pregnant.


#4 – A Natural Pain Reliever and Bodily Defense
Another great bodily reaction of pressing lips with love is that it works with our body to keep us healthy. Kissing dilates our blood vessels, keeping the red highway moving, relieving pressure of headaches and menstrual cramps. Furthermore, kissing lowers the stress hormone cortisol for an elevated sense of well-being and happiness. Lastly, kissing pumps natural antibiotics into our saliva as a defense mechanism, keeping us healthy and preventing cavities. (Source: CNN.com) Against the findings of several recent studies, some infants and toddlers still think that Mom’s kisses make their scrapes and bruises feel better.


So Kiss Away this Valentine’s Day
It’s interesting that our genes, cultural habits, and bodily functions offer as much benefit in kissing as we think they have for our relationships. Sure, scientific reasons don’t prompt the pucker up, but it’s fun to know that all the stolen kisses are helping your body as much as your relationship. So enjoy your kisses this Valentine’s Day, and feel free to tell your loved ones what you learned from this post.


Happy Valentine’s Day from Dr. Marchbanks and his staff!

About Mark C. Marchbanks, D.D.S.

Dr. Mark Marchbanks has practiced dentistry in Arlington Texas since 1983. He enjoys caring for patients young and old. You can find Dr. Marchbanks on
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