What Really Happens To Your Body When You're Lovestruck

"All you need is love." "Love is a drug." "You call it madness, but I call it love." If these famous words about love are any indication, it's clearly more than a feeling — love is a full-body, brain-hijacking experience. For most of us, the sensations are almost as familiar as thirst or hunger, and they're likely just as essential for survival too. "Love is a biological necessity, just like water or exercise or food," Dr. Stephanie Cacioppo, a neuroscientist who studies love, told The New York Times. "My research has convinced me that a healthy love life — which could include your beloved partner, your closest circle of friends, your family, and even your favorite sports team — is as essential to a person's well-being as a good diet."

Because love is so fundamental, the mind and body have unique ways of alerting us of it. You'll likely notice flutters in your stomach, become flooded with excitement (and nervousness) when you see your special someone, and find yourself obsessing over your future together.

So what's really behind these overwhelming feelings? Here's how your body changes when you're head over heels.

Hormones are at the heart of those lovey-dovey feelings

If you've ever felt a little mentally unstable while lovestruck, it wasn't your imagination — love can majorly change how your brain works. A 2010 study published in The Journal of Sexual Medicine found that there are areas of the brain that light up and function together to make you feel infatuated. A chemical cocktail containing hormones like oxytocin and dopamine takes over, encouraging you to bond with your crush — making eye contact and hand-holding feel extra rewarding.

While these hormonal changes may sound sweet, the researchers concluded that their effect on the brain is similar to using cocaine. Moreover, testosterone and estrogen produced when you're lusting over a crush shut down the parts of your brain responsible for decision-making — no wonder you sometimes miss red flags; especially on a first date.

While attraction raises the levels of some hormones, others, like serotonin, drop. Co-director of the Loyola Sexual Wellness Clinic and assistant professor Dr. Mary Lynn told ScienceDaily that "Love lowers serotonin levels, which is common in people with obsessive-compulsive disorders. This may explain why we concentrate on little other than our partner during the early stages of a relationship." Low serotonin is also associated with anxiety, depression, and other mood changes.

Love isn't all in your head

Falling in love profoundly impacts how your brain functions and how you feel emotionally, but you'll likely notice other physical changes in the body, too. For example, there's some truth to the phrase "heart skips a beat." The rush of adrenaline experienced on a first date or when you spot your crush from afar can actually make your heart rate increase, as cardiologist Dr. Reginald Ho explained to CNN.

Feeling butterflies in your stomach is another physical sensation you'll likely notice when you're smitten. According to psychiatrist and neuroscientist Dr. Daniel Amen, a fluttery stomach is triggered by your nervous system. "Your limbic or emotional brain activates the vagus nerve that goes from the brain to your gut," he told Better by Today. "When you get nervous, or when you get excited (as I explain to my patients, it's the same feeling, but it depends on your interpretation of it) this nerve is stimulated that activates the gut."

A 2004 study published in Psychoneuroendocrinology confirmed that cortisol, the body's stress hormone, is higher in people who have recently fallen in love. As EndocrineWeb reported, this, too, can cause a range of physical symptoms including sleeplessness, moodiness, and an upset stomach. Though this may sound uncomfortable, the good news is that cortisol levels eventually stabilize in long-term relationships.