There’s a reason love is so complicated and indescribable — it’s actually three feelings in one. According to a team of scientists led by famous biological anthropologist Helen Fisher, romantic love can actually be broken down into three sensations: lust, attraction and attachment. And each feeling is characterized by its own set of hormones stemming from the brain.
Lust is different than love
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The evolutionary basis for “lust” stems from the need to reproduce. The sex hormones testosterone and estrogen drive lust, which are separate from what is behind attraction and attachment. This is why one-night stands or steamy hookups don’t necessarily lead to long-term relationships. However, it gets complicated because lust and passion are still components of long-lasting love as well.
Attraction is based on obsession
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While estrogen and testosterone drive lust, dopamine and norepinephrine are released when one feels attraction. According to Fisher’s extensive research, humans manifest attraction in the brain areas that control “reward” behavior. In a number of Fisher’s studies, brain scans of people in love showed the primary reward centers of the brain lighting up after they were shown a picture of someone they are intensely attracted to. This helps to explain why the attraction component of love is based on feelings of obsession as well as why the early days of a romantic relationship can be exhilarating.
Attachment isn’t exclusive to romance
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The third category of love, attachment, is associated with feelings of comfort and nurturing as opposed to infatuation and desire. The hormones oxytocin and vasopressin are the fuel for these factors in long-term relationships. And while lust and attraction are pretty much exclusive to romantic love, attachment is also felt through friendships, parent-infant bonding and even how owners feel toward their pets.
Being in love can decrease appetite
When someone is in the attraction phase of love, high levels of dopamine and norepinephrine are released. Dopamine is known as one of the happiness hormones, and these chemicals can make people feel giddy and even euphoric. This reaction can also lead to decreased appetite and insomnia, which means you can actually be so “in love” that you can’t eat or sleep well.
Being in love changes you
If you find yourself watching romantic comedies when you used to only prefer thrillers or if you suddenly love Mexican food when you didn’t before, you might want to credit your partner. A study published in the Journal of Personality and Social Psychology found that people in love often have different interests and personality traits after entering into their respective relationships. One of the study’s authors suggested that people have a more diverse sense of self and an increased self-esteem after falling in love.
Love can be a pain reliever
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A study conducted by the Stanford University School of Medicine found that intense, passionate feelings of love can be used as an effective pain reliever, acting similar to illicit drugs like cocaine. Researchers asked 15 undergraduate students to bring in photos of their romantic partner and photos of an acquaintance. Researchers then showed the pictures to their subjects while zapping their hands with a computer-controlled thermal stimulator to cause mild pain. They found that seeing the image of their loved ones reduced the level of pain they felt. So if you’re about to donate blood and don’t prefer needles, perhaps you should have a picture of someone you love on hand.
Love is blind
Longtime married couple Richard Schwartz and Jacqueline Olds are Harvard Medical School professors and couples therapists who have been studying the evolution of love for decades. In one study, they uncovered the science behind the phrase “love is blind.” In a piece published by Harvard University, Schwartz explained how the feeling of love deactivates the neural pathway responsible for negative emotions such as fear and social judgment. So when you start to fall in love, your ability to make critical assessments shuts down.
Love can make you sick
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If you’ve ever heard someone say they’re lovesick, they may have been onto something. Though it hasn’t been proven that love makes you physically sick, it does raise levels of cortisol, according to Richard Schwartz, associate professor of psychiatry at Harvard Medical School. Cortisol is a stress hormone that has been shown to suppress immune function, making you more likely to get sick.
Being grateful can improve relationships
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Everyone wants to be cared for and appreciated. And studies have found that gratitude can actually improve relationships. For example, one study found that couples who took the time to express gratitude for their partner not only felt more positive toward the other person but also felt more comfortable expressing concerns about their relationship.
The ‘love drug’ is also found in chocolate
When you fall in love, your brain releases a hormone called phenylethylamine, which is known as the “love drug.” The hormone is what’s responsible for making partners feel madly in love with each other. Phenylethylamine is also found in chocolate, which may explain why you can’t stop after one piece.
It takes just one-fifth of a second to fall in love
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Out of all the discoveries scientists have made on the topic of love, the most romantic might just be how quickly someone can fall in love. A meta-analysis study published in the Journal of Sexual Medicine found that falling in love only takes about a fifth of a second.
When a person falls in love, multiple areas of the brain are at work
In the same study, the team of researchers revealed that 12 areas of the brain work together to release euphoria-inducing chemicals that make someone feel like they’re in love. The chemicals dopamine, oxytocin, adrenaline and vasopressin elicit the high sensation one might feel as they get hit with the lovebug.
Love is similar to being high
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You may have heard that falling in love is like getting high, and there actually is some truth to that. A study from the Kinsey Institute published in Frontier Psychology found that the brain of a person falling in love looks a lot like the brain of someone who has taken cocaine. In fact, people in the early stages of an intense romantic relationship exhibit many symptoms of substance addictions, including euphoria, cravings, withdrawal, and emotional and physical dependence. The researchers wrote that romantic love could be considered a powerful “natural addiction.”
The brain falls in love, not the heart
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Many scientists have gone back and forth on whether it’s the brain that falls in love or the heart. Based on her work, Syracuse University professor Stephanie Ortigue believes it is ultimately the brain, though the heart is related. “Activation in some parts of the brain can generate stimulations to the heart, butterflies in the stomach,” Ortigue wrote in the Journal of Sexual Medicine. “Some symptoms we sometimes feel as a manifestation of the heart may sometimes be coming from the brain.”
Love makes you dumb
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Falling in love can make people do questionable and embarrassing things. In fact, research shows that sexual arousal turns off the regions in the brain that control critical thinking, self-awareness and rational behavior. It shuts off the prefrontal cortex of the brain, which is to blame for mistakes, bad decisions and regrettable moments in a new relationship.
Love does hurt
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At times, love hurts, and being “heartbroken” is actually a real sensation and not just something that’s only in your head. It’s called “takotsubo cardiomyopathy” or broken heart syndrome. According to Harvard Women’s Health Watch, broken heart syndrome is a weakening of the heart’s main pumping chamber as a result of severe emotional or physical stress, such as the loss of a loved one or a serious accident. It occurs almost exclusively in women and researchers are still figuring out why it happens. While it’s rare, it is possible to die of a broken heart.
You don’t have to be newly married to be head over heels
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You might think that deep, passionate love is reserved exclusively for the “honeymoon phase” of a relationship, but a 2011 study showed that you can still be madly in love with someone after decades of marriage. A research team at Stony Brook University in New York performed MRI scans on couples who had been married for an average of 21 years. They compared the results with scans done in a prior experiment of couples that were in a newer relationship. The researchers found the same level of activity in dopamine-rich areas of the brain for both the long-married couples and those who were newly in love. The study suggested that as a relationship grows, the spark stays — but some of the initial stress is gone.
The love hormone is two-faced
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A study from Northwestern University revealed that the “love hormone” oxytocin — which has long been known to promote warm, fuzzy feelings of well-being and social bonding — has a dark side too. The surprising research published in 2013 shows oxytocin can also cause emotional pain. The hormone actually strengthens social memory in the brain, and that includes bad memories. These memories can be triggered long after a negative incident. Healthy levels of oxytocin can help people feel connected toward their partners, but if the hormone is elevated, it can fuel toxic habits like jealousy and irritability.
Couples’ heart rates start to synchronize
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Your heart might skip a beat when your crush walks by, but a study found that if you’re in a deep relationship, your hearts might be beating in sync. A study conducted by the University of California-Davis suggests there are physiological signals between two people in love. In fact, couples’ hearts begin to beat at the same rate when they’re in a relationship.