Sunday, October 3, 2010

Love Chemicals

When you fall in love, your bodily chemicals go haywire. The exciting, scary, mysterious and unpredictable elements of love stem from hyperstimulation of the limbic brain's fear center known as "the amygdala". Hyperactivation of the amygdala gives rise to a physical stress response in your body.

Hans Selye, a Canadian endocrinologist, was the first to apply the word "stress" to physical and emotional strain. Before that, "stress" was just an engineering term. Selye, who did the bulk of his research in the 1930s, discovered that the stress hormone cortisol has detrimental health effects in rats. Together with other adrenal gland hormones such as adrenaline and noradrenaline, cortisol prepares the body for a "fight or flight" response.

Stress hormones are secreted in situations of perceived danger. They can be present, even when the danger isn't real. For example, they are present in generous amounts in people with fear of public speaking. They are the little bastards that make your heart break dance, your skeleton turn to gelatin and your new Mickey Mouse voice implant make little noises the first time you stand in front of a 100-person audience.

Falling in love then goes like this. Unpredictability, mystery and sexual attraction make the amygdala go into hyperactivation. This signals to the adrenal glands that something exciting, scary, mysterious and unpredictable is going on. This, in turn, results in the adrenal glands pumping a surge of adrenaline, noradrenaline and cortisol into the bloodstream. Via the bloodstream, adrenaline increases heart and breathing rates, noradrenaline produces body heat, making you sweat, and cortisol provides extra energy fuels for muscles to use.

Love is stressful. Can you quit it? Not easily. When you fall in love, your dopamine levels increase. This motivates you to continue to perform the activities that generated the elevated dopamine levels in the first place.

Love is stressful and highly addictive. It also makes you feel bad, at least periodically. Increased amygdala activation is correlated with a heightened breakdown of extra-cellular serotonin. Serotonin makes you feel good. When your serotonin levels go down, you feel bad. You become depressed or anxious. This is what happens to people in love. They feel good when they are together and horrible when they are apart.

You can now see why one-sided love makes you miserable. Since you are never together with wonder boy or wonder girl, your serotonin-levels are constantly suppressed, your body wants the dopamine-high and your adrenaline glands pump huge amounts of stress hormones into your blood vessels. When you suffer from unrequited love, you are literally at your wits end.


  1. do you know this blog helped me immensely! i have been crushing on someone for nearly two weeks and i have been having physical stress reactions from it - palpitations loss of not like me at ALL - thanks - you made me feel kinda normal!

  2. Thank you. I have moved the blog to this site: Your comment will automatically transfer.