By Casey Frye, CCNN Writer
When my peers and I study for a huge test that’s coming up, some of us just can’t help but chow down on sugary snacks and fattening treats to ease our jittery nerves. It’s a phenomenon known as stress eating, and according to scientists, it’s basically part of our biology.
Researchers usually prove this with rats in their lab. By placing the rodents into small, cramped spaces, they cause the creatures to become extremely stressed out (who wouldn’t be?). Then, when the rats are presented with the choice between healthy or unhealthy meals, they almost always choose the food with the most fattening calories per bite.
“Sometimes, an animal’s calorie intake actually doesn’t increase overall, but the kind of foods it’s eating shifts,” says Kevin Laugero, a Research Nutritionist at the Western Human Nutrition Research Center/ARS/USDA and Professor of Nutrition. “We think it’s a selective focus on these highly energetic or energy-dense foods.”
Why does this happen, though? Well, when animals are stressed out – say, because they’re being chased by a predator – a special chemical known as cortisol is released in the body. This hormone causes the body to breakdown fat in order to fuel their rapid movements. According to researchers, it also causes animals to crave fatty foods in order to have an additional source of energy!
The same happens to humans as well. When the researchers placed a group of volunteers in an interview, which can be extremely stressful, the participants were much more likely to munch on sugary chocolate bars than eat healthy carrot sticks. Not everyone eats when their nerves are shot, say the researchers, but about 80% tend to gobble up relatively unhealthy meals.
“It is possible that some of it is just the reward-based association,” Laugero explains, “but I think with food, there is definitely a metabolic basis. Having a bowl of ice cream when we’re stressed can actually be adaptive. But it’s the repeated nature over time that can be absolutely maladaptive.” Good adaptation versus bad adaptation? I guess I’ll tell my body “thanks, but no thanks” the next time it tells me I need fat to deal with those math problems!