18 Interesting Facts About Kissing You Probably Didn’t Know

According to Scientific American, in the 1960s, British zoologist and author Desmond Morris speculated that kissing evolved from behavior exhibited by monkeys. Primate mothers would chew food for their young and then feed them, mouth-to-mouth and with their lips puckered. Morris believes that this later developed into a way to comfort hungry children, and then eventually to show love and affection. Through evolution, kissing evolved, too.

Kissing might feel instinctual, given that it's such a common sign of affection and love, but it's not an innate action every human being just automatically knows how to do. A 2015 study found that kissing is not the universal way to express desire and love. In fact, per the same research, there are a number of cultures and tribes in sub-Saharan Africa, New Guinea, and the Amazon where people do not kiss. As a result, there's data to suggest that kissing is actually a learned trait, instead of human instinct.

Is constant smooching the key to living a longer life? Maybe! A study conducted by German physicians and psychologists found that men who kissed their spouses every morning missed less work due to illness, got in fewer car accidents, earned more money, and lived about five years longer than those who do not kiss their spouses on the cheek on a daily basis. The explanation? According to researchers, those who kiss their spouse start their day with a positive attitude, while those who don't are less confident.

In a study from 2000, conducted by the University of Lausanne in Switzerland, researchers found that women prefer the scents of potential romantic partners whose genes are different than their own, which, in theory, would allow them to have children with stronger immune systems. These findings suggested that kissing is our low-key, canine-like way of getting information about someone.

A 2007 study found that women can make up their minds about a potential mate after that first kiss. The study looked at 1,041 heterosexual co-eds and found that kissing is more important to women when it comes to deciding whether they want to date someone or not. A similar study in 2013 found that women will typically make a snap judgement about a relationship based on a first kiss. (It's worth noting that both of these studies only examined straight people.)

If you're looking to give your relationship a little boost, try kissing more often. Whether it's a quick peck on the lips throughout the day, or something more passionate in lieu of watching Netflix, upping the number of kisses you give and receive your partner could work to improve your relationship.

A 2013 study in the Archives of Sexual Behavior found that romantic kissing (and other forms of physical contact) can make you feel more attached to your partner and increase the feeling of satisfaction in your relationship.

A study of a little over 1,000 college students at the University of Albany found that men and women prefer different techniques and have different reasons for leaning in for a smooch. Basically, women are kissing someone to find out if they want to date them long-term, while men are kissing someone simply because it feels good and can serve as a means of arousal.

A 2014 study published in the journal Microbiome found that couples who kissed often were more likely to share the same microbiota, which leads to a stronger immune system. (Oh, and by "often," they mean at least nine times each day.)

While kissing is often considered more apart of foreplay than an essential component of sex itself, scientists suggest you remember to get your smooch on between the sheets, too. A 2018 study found that women are more likely to have an orgasm when "deep kissing" happens during sex.

According to Healthline, kissing makes your brain release a whole bunch of feel-good chemicals and hormones, including oxytocin, dopamine, and serotonin.

These chemicals can produce feelings of euphoria, while simultaneously making you feel more affectionate. A 2005 study even found that a really great kiss can produce so much dopamine that the feeling can be comparable to the feeling you get from using narcotics.

A 2003 Japanese study observing 90 participants found that the people who kissed their partners for 30 minutes had significant relief from hives and plasma neurotrophin levels (a sign of allergic reaction). Researchers believe this is because kissing can relieve stress, and stress can lead to allergies.

Research has found that kissing can actually be a really important part of selecting a partner. A 2013 Oxford University study found that women think of kissing as an extremely important part of picking a mate. This isn't even something we realize is happening, either. Instead, via kissing people can pick up on biological cues, like genetic fitness and health.

Kissing someone increases blood flow to your face, working a number of facial muscles in the process. That extra blood flow stimulates the production of collagen and elastin, proteins that leave your skin all glow-like and youthful looking.

A 2017 study published in the journal Scientific Reports found that most people tilt their head to the right when they go to kiss someone, and they don't even realize they're doing it!

Kissing is also an excellent way to bond with your partner. Research from 2014 found that when people kiss on the lips, their brain activity spikes and harmonizes. This synchronization helps our brains understand each other better.

The feel-good chemicals and hormones released during a decent smooth not only give you a natural high, but can also help lower stress and cholesterol levels. Another study found that just 15 minutes of kissing can lower cortisol levels and, therefore, alleviate stress and anxiety.

A 2016 study published in the Journal of Experimental Psychology: Human Perception and Performance found that when you keep your eyes open while kissing, you're less likely to experience all of the other sensations kissing can facilitate. Our brains can't process visual and touch-related stimuli simultaneously, so if your eyes are open, you're too distracted to notice the other good stuff happening.

Studies suggest that women who are at the most fertile part of their menstrual cycle are more likely to pick a partner who seems genetically healthy and fit. That research also found that when women are ovulating, they're more likely to put greater importance on kissing.

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