Physiology is at play, as well. When you're stressed, your body releases cortisol, a hormone that, among other things, plays a role in eating behavior and food choices. Short-term stress, like racing to meet a deadline, typically tamps down appetite. But when cortisol stays elevated, as it does when you're dealing with long-term distress from situations like a monthslong pandemic or job insecurity, it not only stimulates appetite but triggers cravings for highly palatable, fatty, sugary fare. “We've also found that stress might raise the levels of ghrelin, the hormone that signals your body it's time to eat,” says Ariana Chao, a stress and food researcher at the University of Pennsylvania School of Nursing, whose studies have shown that high cortisol and chronic stress can lead to weight gain. All told, along with priming you to crave carbs, stress makes it easier to overeat.
The truth about comfort food
When you're midway through a slice of pizza or a handful of potato chips, you may indeed feel a little less edgy. “Comfort food distracts us from our problems, tastes good and stimulates the brain's reward system, so you get a hit of pleasure,” Albers explains. But as a true stress-relief tool, unhealthy treats are actually no more effective than fruit or vegetables or no food at all, says Traci Mann, a professor of psychology and food researcher at the University of Minnesota. “There's nothing wrong with having a treat when you're stressed. But we've found that if you're eating comfort food to improve your mood, you'd be just as well off eating a bowl of broccoli,” she says.
Sound like a stretch? Know this: In 2018 researchers at UCLA conducted a study in which they monitored participants’ stress with sensors while they delivered a five-minute impromptu speech (subjects were told it would be evaluated by a committee) and then took a five-minute mental arithmetic test. After the ordeal, participants received one of the following: their favorite unhealthy comfort food, their favorite vegetables or fruits, or no food at all. Throughout the process the researchers assessed subjects’ moods with a standard questionnaire, and in the hour after the tests, they collected cortisol at three different times to see whether the groups differed in their ability to recover from stress. “Neither unhealthy comfort food or healthy food had any effect on stress recovery or mood, so if you feel like eating when you're stressed, it makes sense to try having healthy food, like blueberries or avocado, first,” says A. Janet Tomiyama, study coauthor and director of the UCLA Dieting, Stress and Health Lab.