It’s really amazing how many things one simple brain chemical, like serotonin, does in our bodies every day — without our even being aware of it.
Serotonin is a neurotransmitter, a chemical messenger found in the gut, blood, brain and nervous system. It transmits information and impulses across the spaces between the nerve cells, also known as neurons. Serotonin can have a huge impact on our mood, energy, attention, pain, hunger, weight and even our sex life. When your levels are low, you are more likely to get depressed (in the wintertime, for instance). The amount available in your system can make you gain weight, have constipation or diarrhea, reduce your pain, clot blood, heal wounds and even stoke or quell your horniness. It may even be more involved in migraines and sudden infant death (SIDS) than we thought. And there’s a whole class of antidepressant drugs (SSRI’s) used to affect it.
But even though you might not have a science degree, you’ll recognize the effects of serotonin right away. For instance, when you go out to eat and you’re starving — until you start chowing down on all that tempting bread and rolls in the basket they bring to keep you occupied while you’re meal is being prepared. By the time your plate arrives, you don’t feel that hungry anymore. That isn’t from the calories in the bread; that’s serotonin at work.
And by now you’ve also probably heard about what being “hangry” can do to your mood, disposition and even your interaction with your spouse or family. This type of hunger-induced anger can accelerate when your blood sugar drops and you get hungry because the levels of serotonin in the parts of your brain that regulate anger are also dropping at the same time. This can potentially cause feelings ranging from anxiety and stress to uncontrollable anger, especially when you let blood sugar drop way below normal.
“Hunger is one of many external forces that play a part in frustration and temperament,” according to Dr. Scott Weltzer, Vice Chair of Montefiore Medical Center’s Department of Psychiatry. A close relationship like marriage and living with a partner are sort of like a stretched rubber band. “Hunger can be the force that causes it to snap. We are all less inhibited around our loved ones and more likely to lash out at home than we are in the workplace,” he adds.
That’s because Serotonin is nature’s own appetite suppressant. “This powerful brain chemical curbs cravings and shuts off appetite. It makes you feel satisfied even if your stomach is not full. The result is eating less and losing weight,” according to a researcher, Dr. Judith Wurtman in The AntiDepressant Diet.
And it can put you in a better mood. “A natural mood regulator, serotonin also makes you feel emotionally stable, less anxious, more tranquil and even more focused and energetic,” Wurtman adds.
According to researchers at Macalester College, a deficiency of serotonin has been associated with greater aggressive behavior. In fact, low internal levels of this chemical have been linked with higher levels of irritability, impulsivity, aggression, disordered eating and sleeping problems. Medical studies have shown that serotonin’s mechanism affects many different conditions, including alcoholism, clinical depression, obsessive-compulsive disorder (OCD), hypertension, social phobia and even romantic love.
Physicians prescribe copious amounts of SSRI’s, a class of antidepressants, to increase serotonin levels in many patients suffering from depression, bipolar disorder, and other mental challenges. One of the problems they’ve observed, though, is that these also lower sex drive because they concentrate serotonin in the nerves.
Serotonin may actually be involved in the “love versus sex” divide. When serotonin is low, researchers say, it also tends to increase sex drive; whereas higher serotonin levels are also associated with an increase in oxytocin, the so-called “love” hormone. This seems to reflect women’s preference for more bonding, cuddling, and lovemaking versus men’s noted penchant for straight physical sex. Ample amounts of serotonin make for more “loving” feelings.