The science of love: Why do we fall head over heels?

Falling in love might seem magical and mysterious, but it’s actually the result of a series of hormones and chemicals released by your brain.

The 3 stages of falling in love

1) Lust

When we reach puberty, testosterone and oestrogen become active in our bodies. These hormones create the desire to experience love, and so we start looking for a mate. Who we lust after is influenced by a number of factors. Looks and personality play a big role, and research has revealed that we tend to be attracted to people who remind us of our parents. We also sniff out potential mates, and studies have found that we tend to prefer the smell of others who have an immune system that is different from our own. This is a trait also found in the animal kingdom, as it increases the chances of having healthy offspring.

2) Attraction

When you become attracted to someone, a series of chemicals are released in the brain. Dopamine, which is also activated by cocaine and nicotine, produces the feeling of bliss and is also associated with addiction, leading to a loss of appetite and sleepless nights. Norepinephrine activates stress responses, causing an increased heart rate and sweating, and a protein called nerve growth factor is produced, which is thought to intensify romantic feelings. Serotonin levels fall to a similar level found in people with obsessive-compulsive disorder, making it difficult to keep the object of your desire out of your thoughts, and you also begin to idealize them, becoming oblivious to their flaws.

3) Attachment 

If a relationship is going to last beyond the attraction stage, a strong bond must form. Two key hormones, oxytocin and vasopressin, are involved in forming this long-term commitment. Oxytocin, known as the cuddle hormone, is released when we hug, kiss and have sex and helps to establish trust and intimacy. It’s also released during childbirth, helping to strengthen the bond between mother and child. Vasopressin, an antidiuretic hormone responsible for regulating the body’s retention of water, is also released during sex and encourages monogamy and protective behaviour. Endorphins also play a key role in the attachment stage, suppressing pain and creating a sense of security when released during physical contact.


Top 5 love facts

1) Aphrodisiac food

Chocolate contains phenylethylamine, a chemical that causes the release of dopamine and norepinephrine, the key hormones that help us fall in love.

2) Instant attraction

It only takes between 90 seconds and 4 minutes to decide if you fancy someone, and 55% of attraction is based on body language alone.

3) Monogamous animals

Only 3% of mammals mate for life. Animals that do find a lifelong partner include gibbons, swans, wolves, albatrosses, penguins, eagles and termites.

4) Natural painkiller

Simply looking at a photo of the one you love, or even thinking about them, increases levels of oxytocin, the body’s natural painkiller.

5) Broken Heart Syndrome

Also called stress-induced cardiomyopathy, it is caused by an emotionally stressful event, such as a break-up, and causes sudden intense chest pain.

This article was originally published in How It Works issue 69, written by Jo Stass

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