Sex Ed

Why Do We Kiss?

July 6, 2016 by Justin Lehmiller

In the United States and many other parts of the world, kissing is one of the most common sexual and romantic behaviors that exists; however, kissing is far from being a universal activity. In fact, researchers haven’t found any evidence of kissing in a surprisingly large number of cultures around the world.

But in those cultures where kissing occurs, why is that? I mean, how did locking lips, touching tongues, and swapping spit ever become a thing in the first place?

In my latest article over at Playboy, I explore the most popular scientific theories that have been proposed to account for the origin of kissing. Yes, of course, part of the reason we kiss is because it feels good–however, many scientists argue that kissing has a much deeper meaning. Specifically, they argue that kissing helps us “size up” potential partners, to express affection, and to exchange microorganisms that may be beneficial to our health and/or the health of our offspring.

Check out the full article for the details. While you’re over at Playboy, check out the rest of my Hard Science column to learn more about the science of sex. Some of my other recent articles include:

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Written by
Dr. Justin Lehmiller
Founder & Owner of Sex and Psychology

Dr. Justin Lehmiller is a social psychologist and Research Fellow at The Kinsey Institute. He runs the Sex and Psychology blog and podcast and is author of the popular book Tell Me What You Want. Dr. Lehmiller is an award-winning educator, and a prolific researcher who has published more than 50 academic works.

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