The science of kissing

Never underestimate the power of the pash

How do you know if they're 'the one'? Just pucker up! Locking lips either magnetises us to the right mate or warns us of the wrong one. Naturopath Caroline Robertson explores the science of kissing - philematology.

Where did kissing come from?

From the ancient Kama Sutra to modern kissing couples – smooching seems to be an innate impulse. Anthropologists suggest it starts with our sucking reflex as breastfeeding babies, and from the practice of pre-chewing food and mouth feeding to offspring. Humans aren’t alone in this lip-smacking ritual. Bonobo chimps can kiss for over 10 minutes, dogs lick faces, horses and cows rub their mouths on necks, birds tap beaks, fish kiss and even elephants poke their trunks in each other’s mouths.

The word kiss comes from the German term kuss echoeing, or ‘the action’. Though kissing is a popular practice in most places, there are some African countries that find it repugnant. Then there are variations, such as the Maori and Inuit style of nose nuzzling and sniffing. Kissing is intrinsic to mating rituals worldwide. But why would we want to exchange one billion bacteria through kissing over an average of 15 days in our lifetime? It turns out that kissing is much more than a token of affection, it’s more an emotional catalyst. Swapping spit unleashes a chemical cascade that can make us fall in love, and sustain our connection.

Love’s language

“A kiss is a lovely trick designed by nature to stop speech when words become superfluous.” – Ingrid Bergman

‘First comes kissing then comes marriage then comes the baby in a baby carriage.’ So goes the nursery rhyme. In fairytales, a kiss can turn frogs to princes, mermaids to girls and revive sleeping beauties. In movies, we all wait for that cathartic kiss, enjoying the passion and connection sizzling on screen. 

A kiss is not just a kiss. It can be the kiss of life or the kiss of death. A first kiss can form the foundation of an enduring attraction or confirm bad chemistry. More than just mouths mushing together, a kiss is the culmination of all our senses – sight, smell, sound, touch and taste. These kissing cues convey to us whether our DNA wants to date their DNA and make healthy babies. Women are attracted to men with very different DNA gauged by their gene’s histocompatibility complex (MHCs). This ensures that offspring with genetic diversity will be strong enough to survive diverse challenges. However, beware contraceptive pill poppers – you are attracted to men who have poor genetic compatibility. MHCs in our scent and saliva make sniffing and swapping spit a chemistry experiment. Trust your senses, because they can be smarter than your thoughts. Recall your past partners – could you sense synergy or static from the first kiss? Did you melt into them like warm dough or was there an acidic taste on your tongue that turned you off? Did you love having their taste and scent on you or did you shower and brush your teeth hastily? 

Never underestimate the power of the pash. According to research at The University of Texas at Austin, 59 per cent of men and 66 per cent of women saying they ended a budding relationship because of a bad first kiss. Smooching skills can give a sneak preview of our sexual style. Some are like a soft, swirling symphony and others like a cat playing violin with their tongue…a definite turn-off for some. With a good kiss, our whole body leans in for more, feelings overwhelm us and time stands still. This sweet mouth meeting can be the “honeyed seal of soft affections, tenderest pledge of future bliss, dearest tie of young connections, love’s first snowdrop, virgin kiss”, as poet Robert Burns wrote.

Ecstatic essence

It’s hard to forget that first magical kiss. With my mate it wasn’t so much fireworks, more a warm welcome into his world. I was addicted from the start as I sunk into his soft marshmallow pillows, every pore wanting to press against him in a full body kiss. 

Alfred Tennyson described it best in his
poem ‘Fatima’: 

“O Love, O fire! Once he drew

With one long kiss, my whole soul thro’ 

My lips, as sunlight drinketh dew.” 

Lips are one of the most nerve-rich and exposed erogenous zones. The gentlest brush can stimulate pleasurable sensations through the entire nervous system. Sucking the upper middle lip excites the clitoris, which is why some women orgasm from pashing. No wonder we get giddy from a passionate kiss. It increases blood to the brain, speeds our pulse, dilates blood vessels, causing flushing; contracts sexual muscles, dilates pupils, floods blood to swelling genitals and heightens the sense of touch, smell and taste.

Deep kissing involves up to 34 facial muscles, burns around 6.4 calories a minute and serves a cocktail of chemicals. With attraction, the alchemy of a duo’s fluids is likened to a fountain of youth in ancient India and China and called ‘nectar breathing’ by Samuel Taylor Coleridge. As tongues tussle, women receive aphrodisiac testosterone ambrosia from the male’s store, which may be why men prefer sloppier kisses. The smell of compatible pheromones drives our desire. The sight of each other getting aroused further arouses us. The contraction of our mouth, stimulation of nerves and saliva essence triggers a fountain of feel-good hormones. Research has shown that kissing couples have increased levels of endorphins, which give an addictive, happy high. Oxytocin bursts – a bonding love drug that makes us want to kiss forever. Kissing reduces the stress hormone cortisol – according to a study conducted by Wendy Hill, a neuroscience professor at Lafayette College, Pennsylvania – and the longer the couple’s relationship, the greater their decline in cortisol and less stress, according to the study. With sensual kisses, we’re washed in a blissful bath of dopamine, seratonin, adrenalin and phenylethylamine – all contributing to our love drunk state. 

Kissing styles

The poet Percy Bysshe Shelley, called a man’s kiss his signature. If you want to be a killer kisser, clean teeth, establish emotional rapport, wait for a quiet private moment, tune into the other person, start softly and slowly, and then climax into a crescendo of passion. Pause to stroke, whisper sweet nothings like “you’re such a good kisser”, “I love your lips”, “you’re so gorgeous”, “I never want to stop kissing you”. But talking too much can be a turn off, so add little ‘mms’ and ‘ahhs’ for encouragement. Try variety in your kiss such as gentle pecks around the lips, little bites, holding and kissing the face, neck or whole body, little sniffs, licks, sucking one then both lips, stroking a lip with your tongue, dipping your tongue in and out, shallow then deep, swirling tongues together, moving your head from left to right, stopping and smiling in their eyes. Soak up the sublime sensuality, for this could seal the beginning of a beautiful relationship. May you enjoy a lifetime of lovely kisses. As poet John Keats said: “Now a soft kiss – aye, by that kiss, I vow an endless bliss.”

For over 20 years, Caroline Robertson has practised and taught naturopathy, homoeopathy and Ayurveda. After kissing many frogs, she is happily settled with her prince in Far North Queensland. For a consultation, healing retreat or healing CD please visit 

NEXT: Will your relationship last? 

Rate This

Average: 5 (1 vote)
The information presented on this website is not intended as specific medical advice and is not a substitute for professional medical treatment or diagnosis. Read our Medical Notice.