What’s that spark we feel when meeting someone that ignites our passions? What exactly is that odd feeling of elation and fixation? Valentine's Day is the most romantic of the year, so let's delve a little deeper into the science of love:


The right chemistry

What happens in your brain when you’ve spotted someone you fancy?

Twelve areas of the brain work simultaneously to release a cocktail of feel-good chemicals such as dopamine, oxytocin, adrenaline and norepinephrine, according to a 2010 study led by Prof Stephanie Ortigue at the University of Syracuse in New York.

This potent elixir triggers specific physical and psychological reactions in the body. Oxytocin promotes bonding between mates; dopamine creates feelings of euphoria; while adrenaline and norepinephrine are responsible for the sleepless nights and general preoccupation that often accompany the early stages of a relationship.

On the other hand, love can lower serotonin levels – a chemical imbalance that’s also seen in people with obsessive-compulsive disorders. This may explain why our object of desire can often end up consuming our thoughts.


The scent of love

Want to find out if you’re a good match? Give that special someone a sniff.

The cells in the human body that keep out foreign invaders influence a person’s odour. Your body odour therefore smell carries clues to the type of immune system you have – some people's immune systems can be incompatible, leading to offspring with a poorer ability to fight pathogens.

A recent study by scientists at Germany’s Max Planck Institute for Evolutionary Biology found that women preferred wearing perfumes containing an odourless substance designed to mimic their own unique immune system.

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So, if added to perfumes, these synthetic chemicals could potentially be used to broadcast people's personal body signatures and entice compatible mates.


Share your DNA – with a kiss

Kissing, it turns out, involves sharing a lot more than just your passion.

In a study published in 2014, researchers at Comenius University in Bratislava, Slovakia confirmed that DNA is shared between lovers who passionately kiss. This means that you weren’t just tasting saliva and Jägerbombs in that nightclub last weekend, but also a little piece of your companion’s genetic material.

This research could be used to help identify sexual predators in cases of assault or even to catch cheating lovers.


What is love?

Believed to have evolved to direct human reproduction, romantic love exists mainly to motivate us to seek relationships and sex with an appropriate partner – at least, that's according to Richard Davidson, a Professor of Psychology and Psychiatry of the University of Wisconsin-Madison in the US.

But, of course, it’s not all spurred by baser motives. To quote the late, great mathematician and philosopher Bertrand Russell:

"Love is something far more than desire for sexual intercourse; it is the principal means of escape from the loneliness which afflicts most men and women throughout the greater part of their lives."

It’s also been suggested that love has evolved as a way to promote parental support of children, who are dependent on parental help for a long period of time.


What turns you on?

Essentially, what we find beautiful and attractive is based on our recognition of characteristics in a healthy, fertile potential mate.

An international team of psychologists in 2010 found that men tend to be attracted to women who are shorter than they are, have a youthful, symmetrical face, and who possess features such as full breasts, full lips, and a low waist-hip ratio.

Women, on the other hand, tend to be attracted to men who are taller than they are and who display masculine, symmetrical faces, as well as broad shoulders and a V-shaped torso.

People are also generally attracted to those with faces resembling their own. According to a 2004 study by scientists at the Universidad Simón Bolívar in Venezuela, this is because similarly-faced people are recognised as being genetically compatible.


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