An exploration into chemicals of love, and whether people know as much about love as they think

Written by: 
Haeley van der Werf


Love makes a person’s heart race and their palms sweaty. It can make a person’s stomach fill with butterflies, and they can go days without even thinking about eating. But what is love really? According to BYU–Hawaii professors and experts at Harvard University, a part of love is chemicals and hormones racing through a person’s brain, sending signals through their body. Although there are some aspects of love people understand, Dr. Jess Kohlert said there is so much more about love they don’t know.

What does love look like inside your brain?

Kohlert, department chair of Psychology at BYUH, broke down love into three categories. “This thing called love can be parceled into three areas. One is lust, one is attraction, and one is attachment. There are different chemicals for each one of those things.”

Explaining the difference between the three categories, Kohlert said, “Lust is a reproductive urge. Those chemicals are primarily testosterone and estrogen. Testosterone increases libido (sex drive) in both males and females. Estrogen can do the same thing, but it’s not as powerful in either sex.

“Attraction has to do with the rewarding systems of the brain. Dopamine is important for this rewarding system. That’s when you get this giddy feeling. Norepinephrine excites us or exhilarates us. You could go days without eating or thinking about eating because you’re so in love.”

Kohlert said the last kind of love, attachment, involves the chemicals oxytocin and vasopressin. “Warm cuddling with an individual will release oxytocin. Oxytocin is released during sex, cuddling, or any close contact. Vasopressin is involved in that attachment as well.”

Kate McLellan, an assistant professor of Exercise and Sports Science, explained how love is both a survival reflex and an attraction instinct. “There is a psychological and biochemical aspect with chemicals in your brain. Your heart racing and the butterflies in your stomach are the result of chemicals and neurotransmitters. There is a cold side of love, which comes from oxytocin and dopamine.”

The article, “Love and the Brain,” by Harvard University talks about a study, “Photos of people they romantically loved caused the participants’ brains to become active in regions rich with dopamine, the so-called feel-good neurotransmitter.”

Additional findings by the study showed, “When we are falling in love, chemicals associated with the reward circuit flood our brain, producing a variety of physical and emotional responses—racing hearts, sweaty palms, flushed cheeks, feelings of passion and anxiety. Levels of the stress hormone cortisol increase during the initial phase of romantic love.

“As cortisol levels rise, levels of the neurotransmitter serotonin become depleted. Low levels of serotonin precipitate what [Richard] Schwartz described as the ‘intrusive, maddeningly preoccupying thoughts, hopes, terrors of early love’ — the obsessive-compulsive behaviors associated with infatuation … In addition to the positive feelings romance brings, love also deactivates the neural pathway responsible for negative emotions, such as fear and social judgment.”

How do people fall in love?

McLellan said, “There are two different kinds of falling in love. People often assume men fall in love based on physical attraction, and women fall in love based on an emotional connection. It’s actually exactly opposite. In men, what creates love is when they feel they can trust someone. It takes longer for guys to fall in love.

“Girls fall fast based on physical touch. It’s physical, and then the biological factors come in and girls can’t distinguish between them. Men fall when they are committed, and girls fall based on physicality.”

According to McLellan, this misconception stems from not realizing the difference between attraction and love. “In initial attraction, guys think about the physical aspects. They don’t think about the long term. They just think about now. Girls start with the end in mind. They are attracted to successful people who would be a good mate initially, but in the long run, physical attraction is what keeps them in a relationship.”

Why do people fall out of love?

According to McLellan, “The hormones start to fade away. Choosing to stay in love is a conscious act, not a reactive one. This is why you need to keep dating your spouse. As you go through hard things with your spouse, you become bonded. It all becomes mental … You become attracted to their mind, which gives you the ability to stay strong. Your reason for staying changes. If you keep dating your spouse, you keep the chemicals going.

“A bishop once told me when couples are going through problems, the first thing they stop doing together is they stop praying together. They don’t want to have that emotional connection. Spiritual experiences bond us. Positive things like going to the temple and feeling the Spirit make you feel more bonded.”

A common time for divorce, McLellan said, is about seven years into a relationship. “The seven-year itch happens because that is a major time for a drop off in hormones.

“Another common time for divorce is as kids hit milestones and leave the house. You realize your relationship is based on your kids and not on each other.”

In the end, do people really know that much about love?

According to Kohlert, “When it comes right down to it, we don’t know. We have some ideas. We have some things that look like they’ve fallen into place, but as a whole, we don’t know.

“We know much more than we used to know, but we’ve barely scratched the surface … There are components we seem to understand, but we don’t know how it all fits together.”

As the Harvard article states, “Love may well be one of the most studied, but least understood, behaviors. More than 20 years ago, the biological anthropologist Helen Fisher studied 166 societies and found evidence of romantic love — the kind that leaves one breathless and euphoric — in 147 of them.

“This ubiquity, said Schwartz … indicates, ‘there’s good reason to suspect that romantic love is kept alive by something basic to our biological nature.’”


Date Published: 
Wednesday, February 27, 2019
Last Edited: 
Wednesday, February 27, 2019