Why do we crave comfort food? UC scientists show us

We reach for "comfort food" when we're under stress, and we often feel guilty about that relief. But research from a University of Cincinnati laboratory suggests that the sweet stuff can actually calm the mind and the body.

“It’s not just something in your head, but it’s a real response,” said Annie Egan, a UC doctoral candidate in neuroscience who conducted the research at the UC-Reading laboratory under the direction of Yvonne Ulrich-Lai, associate professor of psychiatry and behavioral neuroscience.

Ulrich-Lai noted that more research is needed to understand the reasons for the improved response. But she said Egan's work with lab rats indicates that we might want to lighten up on the judgment when people, especially women at certain points of their menstrual cycle, reach for a sweet snack to ease stress.

“You’re somehow made to feel that there’s a poor moral judgment to do this, but this research shows that there’s a reason that people are doing this,” she said. “There’s still negative consequences to your health to eat that stuff, but maybe we can use this information to help others make other choices.”

Earlier research in Ulrich-Lai’s laboratory showed that male rats that were given a sugary drink as a twice-a-day treat responded to stress better than rats who got plain water. In some male rats, the stress relief lasted as long as four weeks. Egan wanted to see how female rats, with the additional factor of ovulation cycles, would perform with the same snacking plan.

One group of female rats got twice-daily treats of the sugar water for two weeks, while a second group got the plain water. The researchers then stressed the female rats by putting them in a ventilated plastic tube for a short time. Afterward, Egan drew blood from each rat for analysis.

Like the male rats, females that got the sugar treat had a lower response to stress, with reduced production of stress hormones and an increase in certain brain proteins. The intriguing finding was that the improved stress reaction occurred only at the stage in the rats’ ovulation cycles when levels of estrogen were high. The research suggests that comfort eating has unique effects in the female brain that vary across the ovulation cycle.

Egan and Ulrich-Lai said they aren’t comfort-food eaters. Ulrich-Lai is a gardener and Egan is a runner. But they said their results could open a new field for research.

“What has always struck me personally is that there is this conception in the public that comfort food makes you feel better,” Ulrich-Lai said. “What we know now is that it’s not just an emotional response but a physiological response as well.”

Egan presented the research this month at the annual meeting of the Society for the Study of Ingestive Behavior in Porto, Portugal.