Rewind to the moment of your first kiss. If it was anything like mine, it was most likely awkward, exciting and all about trying to figure out how to make sure our braces stayed out of it. If you think about it, kissing is kind of an odd concept. Two people (or more, if you’re into that) locking lips and getting each other’s saliva everywhere. Now that I’ve probably completely turned you off, let’s talk about the science behind this loving, yet sometimes disgusting, act of affection.

So, why do we kiss? If you’ve ever Googled this question before, you’ve probably come across the classic answer that kissing developed from an ancient behavior in which mothers would “kiss feed” their children. Aka, they would pass food from their mouth to their children’s mouthes. I know, it’s very sexy. And while it may explain the initiation of kissing, it doesn’t give us the answer to this: Why do we keep doing it?

I’m sure we can all agree that kissing feels good. Great, even. Though it’s scientifically proven that we tend to exchange up to 80 million bacteria (ew) while doing it, it’s still incredibly intriguing. The romantic benefits are endless. Kissing brings us closer to our partners not only physically but emotionally as well. Somehow, through lip-to-lip contact, we gain a sense of passion towards a person that most other physical interactions don’t allow.

Are you ready for something creepy? In Sheril Kirshenbaum’s Washington Post article, “Why Is Kissing So Much Fun?” she explains that kissing feels good to us for several reasons. A primary one is that our lips are stimulated with senses of security, love and affection from a very early age (i.e. when we were nursed/bottle-fed). This is what makes the kissing sensation so craveable for us decades after our first experiences with lip pressure.

Surprisingly, our lips are one of the body’s most sensitive areas and are crowded with super powerful nerves. And guess what? These nerves create intense feelings of pleasure. Along with the nerve-endings, there are several other impacts on the body when we kiss. Chemicals such as dopamine and adrenaline are released into the body creating feelings of excitement and desire. Oxytocin makes us feel attached to our partners and can even contribute to the “falling in love feeling,” while our Cortisol levels drop to make us feel more relaxed (unless you’re like me, then you’re always a nervous mess).

Passionate kissing can be compared to a drug: it’s effects on the body and mind cause us to constantly crave a partner’s lips. Pretty crazy to think about considering the ritual began with our mom’s spitting food into our mouths. Despite the crazy science and stories behind the initiation of this ritual, we still value kissing as one of the most intimate acts of love in our culture. And rightly so. Kissing provides us and our partners with love, passion and a deep connection with one another. Happy making out!