Love is a powerful, mysterious, wonderful, overwhelming, complex, and confusing force.
It can fill us with joy and inspire us to accomplish great things. It can also cause us to act in strange and silly ways.
Love helps us survive and thrive. It’s how we connect with others and find meaning in our lives.
And as love sweeps over us, a chemical cocktail of hormones and neurotransmitters flows through our brains and bodies, influencing our moods, thoughts, and behaviors and producing the physical and emotional reactions we associate with being in love.
The Hormones of Lust
Although not all types of love require lust, sexual attraction is often an essential piece of the puzzle, especially in the early stages of a romantic relationship.
Lust is propelled by the gonadal hormones testosterone and estrogen.
Elevation of these hormones increases sexual desire and can lead to the physical changes we associate with sexual arousals, such as increased heart rate, shallow breathing, dilated pupils, and blushing.
Women tend to feel an increased sexual desire during ovulation when testosterone levels are at their highest.
And for all sexes, sex drive tends to diminish when these hormone levels decline (with age, typically).
The Rewarding Chemicals of Attraction
Love is rewarding—it activates the brain’s reward and motivation pathways.
Dopamine is one of the key neurotransmitters involved in these pathways and is associated with cravings, reinforcement, and motivation. The underlying neurochemical encourages you to seek out activities that make you feel good and avoid those that don’t.
Serotonin is another neurotransmitter that plays a role in love. It’s involved in the brain’s pleasure and reward systems and regulates mood and social behaviors. Low serotonin levels have been linked with depression, and some antidepressant medications work by increasing serotonin activity in the brain.
In love and attraction, there is also an increase in norepinephrine activity. Norepinephrine is a stress hormone that’s involved in the fight-or-flight response. It’s responsible for the increased energy, alertness, and focus you feel in the presence of someone you’re attracted to.
These neurochemicals work together to compel you to make your moves and come back for more.
The Attachment Chemicals
For love to last, an emotional bond must keep couples together even when the passionate arousal of early love fades.
In addition to dopamine, oxytocin plays the starring role in attachment.
Oxytocin is sometimes called the “trust hormone” because it’s involved in social bonding and trust-building. It promotes feelings of comfort, closeness, and attachment.
It’s released during breastfeeding and childbirth, and it plays a key role in parent-child bonding. Oxytocin is also released during sexual activity and simple physical contact like touching, holding hands, hugging, or cuddling.
And when oxytocin levels are high, people tend to feel more relaxed, generous, trusting, and happy.
Explaining love as a series of neurochemical reactions may take some romantic mystery out of it, but it doesn’t make love any less special.
These neurochemical reactions are part of what makes love such an amazing, life-changing experience. When we’re in love, we feel alive and connected to others in a way that’s difficult to put into words.
Love fills us with happiness, motivation, and a sense of purpose. It helps us form lasting bonds with others and even contribute to a longer, healthier life.