The Science of Love: How our bodies help determine attraction and commitment

Ah, love! For thousands of years, scientists and philosophers have been looking for scientific proof of love. Plato was the first to coin the term “other half” in ancient Greece, speaking to the sense of longing we feel when we’re in love. In the Middle Ages, people believed that lovesickness was a genuine physical ailment related to an imbalance of the four humours (blood, bile, melancholy, and phlegm) and received treatment for it.

Today, we know so much more about the nature of love and how our biochemistry affects romantic partnerships. But what exactly happens when we fall in love, and how do our bodies contribute to maintaining our emotional connections?

Love and the Five Senses

When we fall in love, it’s with our whole body. The mere sight of a person we’re romantically attracted to makes us begin to experience desire. Physical touch, like hugs, handholding, or kissing, triggers our brain to release oxytocin, one of the “happy hormones,” present in the early stages of our relationship.

When we see someone we’re attracted to, we also release pheromones, which prompt a social response in members of the same species. Even being around someone who smells similar to us or whose odor we identify as pleasant can trigger the release of another “happy hormone” called dopamine.

As with smell, tasting something we enjoy also triggers a dopamine release. Interestingly, because we’re naturally drawn to sweet things, one study found that we are even more likely to be attracted to someone after they’ve eaten something sweet. (Sweets for the sweet, indeed!)

Our sense of hearing also plays a role in our love lives. We deepen our connections with our loved ones when we speak to them and even when we listen to music together. (Mixtapes, anyone?)

The Three Stages: Lust, Attraction, and Love

We don’t fall in love all at once. Instead, it’s a gradual physical process. When we first become attracted to someone, testosterone and estrogen drive our feelings of desire or lust, making us nervous and excited when we see them.

Eventually, we may move on to feeling an attraction to that person. People describe it as feeling high or drunk on love. Indeed, attraction can lead to feelings of euphoria. During this stage, our bodies release dopamine, adrenaline, and norepinephrine, which lead to a sense of joy, excitement, and an overall increase in alertness, arousal, and attention.

Finally, we form a strong emotional attachment to the people we love. As our bonds become closer and more intense, we release more oxytocin and vasopressin (a hormone released during sex that plays a vital role in commitment and attachment).

The Chemistry of Love

There’s a reason we speak of “good chemistry” when we refer to our connections with romantic partners. Various hormones, chemicals, and neurotransmitters are responsible for our growing romantic/sexual feelings. As these hormone levels increase in the body, you begin to realize you’re physically attracted to the other person (with exceptions such as people on the asexual spectrum). And, of course, desire or lust can happen independent of attachment and without leading to love.

Once we become attracted to someone, the reward centers in our brains begin to fire and release dopamine, norepinephrine, and serotonin. Simply being physically close to them releases dopamine, which makes us feel rewarded.

The feelings of giddiness and euphoria are thanks to norepinephrine. When your heart races and your palms sweat, you can thank norepinephrine; it’s even responsible for the sleepless nights and the lack of appetite we tend to experience when first falling in love.

Getting Attached

Of course, for any relationship to last, the people involved must eventually move past the desire and attraction phase. As partners become attached and more deeply committed, their bodies release oxytocin and vasopressin, reinforcing their attachment.

Interestingly, we release these hormones for all types of love, not just in response to romantic feelings. Nicknamed the “cuddle hormone,” oxytocin gets released during childbirth and breastfeeding as well as when spending time with non-romantic loved ones, supporting the release of additional serotonin and reminding us why we love them. And vasopressin increases our willingness to engage in mutually beneficial types of cooperation.

Why Science Still Can’t Fully Explain Love

While scientists have a good handle on hormones and how they relate to love, we may never understand the science of love fully. For example, science can’t explain (at least not yet) why we’re attracted to the people we’re attracted to. Even when we think we know what we want in a romantic partner, we aren’t always drawn to the person who fits the bill.

While studying relationships, attraction, and love, researchers have found that love is, in essence, chaotic, making it impossible to predict what people will do as they navigate a slew of choices and decisions in their relationships.

So, while we don’t know everything about love, we do know (in the words of Hugh Grant in the cult classic film Love Actually), “If you look for it, I’ve got a sneaky feeling you’ll find that love actually is all around.”

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