Teen Stress
November 4, 2003
ScienCentral News

Are teenage girls more stressed than boys? Researchers are examining the relationship between their sex hormones and their brains for clues.

Brain Thermostat
Some adults may think youth is wasted on the young, but teenagers actually face a multitude of stressful situations on a daily basis.

"As adults we like to think that we have the most stress, but that's probably not true," says Elizabeth Young, professor of psychiatry and research scientist at the University of Michigan Mental Health Research Institute. "Not doing well in school, having problems with your friends, parents, boyfriends, girlfriends, those are all things that are well known to have big effects on causing depression." Teenagers, Young says, "have a lot more of these life changes than those of us who are in stable relationships and are raising a family."

When we are in stressful situations, our bodies make a hormone called cortisol that helps us deal with stress by "[telling] the body in general that this is a time of stress and you need to take action," says Young. "In the old days, when we were living in the wild, taking action might have been running away, getting yourself out of danger. So this system, which maybe was designed to deal with escaping predators in the wild, is now being used to face breaking up with a boyfriend. You may not need so much of it when you break up with a boyfriend–that's a different kind of stressor–but we are still activating the system."

Normally, when the stressful situation has passed, our brains turn off production of cortisol–a good thing, because too much cortisol can be harmful. "It's kind of like a heating system," explains Young. "If you need heat, your furnace comes on, but once the heat goes up to a certain point, the thermostat kicks in and turns it back off, so it doesn't get too hot. So it's very important for cortisol to stay in a normal range, and if it gets too hot for too long, it can cause a lot of ill-health effects."

Young says that this thermostat in the brain doesn't seem to work as efficiently in teenage girls as it does in teenage boys, and suspects that female sex hormones like estrogen and progesterone, which are activated in girl's bodies at puberty, affect the brain's sensitivity to cortisol – in effect, cranking up its thermostat. "The stress hormones and the sex hormones are talking to each other," says Young, "and they are having an effect, and this could explain some of the greater stress responsiveness we see in women."

To investigate this, Young's colleague, Margaret Altemus, a psychiatry professor at Weill Cornell Medical Center in New York, tested the blood of stressed female rats, and found that levels of the sex hormone progesterone remained high long after the stress was gone.

"We think that progesterone is one of the critical signals that makes the thermostat in the brain less sensitive to the stress hormone cortisol," Young explains. "When progesterone is high, it's like the thermostat was just set to a higher level. But when you have your thermostat set higher you have more heat, you're already hot. You don't want more heat. You want to turn it off. So it's not turning off because it's set too high."

And too much cortisol can add to the already stressful world of teens. Young recommends that although girls may be more at risk, parents and teachers recognize the challenges both girls and boys face and help them cope with their stressful lives. "We think it's very important for parents and friends to recognize that teenagers really do undergo a lot of life stressors. Teachers, too, probably need to recognize this. We have to help our kids cope with those problems that develop during the teenage years."

This research was published in the Annals of the New York Academy of Sciences, and was funded by the National Institute of Mental Health and the Pritzker Foundation.