The science behind why some people are eating their way through the pandemic

It isn’t only real. It’s science.

Anxiety and stress produce the hormone cortisol, which triggers increased appetite. It’s a reflex designed to store up energy in response to an immediate threat, as in “when we had a woolly mammoth chasing us,” said Katie Ziskind, a therapist and counselor. But it’s stuck around through the ensuing 4,000 years of evolution.

Eating foods such as sugar and carbohydrates can, in turn, make people feel better by prompting the release of yet another chemical in the brain — dopamine, which is associated with pleasure — in the same kind of reaction produced by drugs.

“The negative emotion tells our brain, ‘This is unpleasant; make it go away,’ ” said Jud Brewer, a neuroscientist and addiction psychiatrist at the Brown University School of Public Health. “So we eat, which really jacks the dopamine system and gives us this temporary distraction. That’s the main thing that’s happening.”

Exactly what people are being driven to eat by these chemical signals are the kinds of foods that are comparatively unhealthy — most notably, with lots of sugar.

“It’s not going to be your healthy green salad with lettuce and spinach,” said Uma Naidoo, director of nutritional and lifestyle psychiatry at Massachusetts General Hospital and the author of “This Is Your Brain on Food,” out in August. “Someone who has eaten a usually healthy diet is now eating more sugar at home.”

Even in comparatively normal times, people turn to food for comfort. “They get together over meals or for birthday parties,” said Teresa Fung, a professor of nutrition at Simmons University. “Even with unpleasant things such as funerals, what do people do? They eat.”

Trouble is, chronic modern-day stress is different from momentary prehistoric danger, and once they switch on, it keeps these various behavioral signals from switching off. So people just keep craving high-energy foods with sugar and fat, which accumulates where it’s most easily stored: around their middles.

“I am worried about it,” Karon said. “I am worried that now I have a birthday cake and a tres leches cake in my house.”

But she said she also finds it soothing to cook and bake, especially since her 26-year-old son moved home to ride out the pandemic with his parents.

“That was the first thing that happened: My kid came home. So I’m cooking every day. To be able to cook for him and to bake just fills my heart and it makes me so happy.”

That’s why many nutritionists say they aren’t overly worried about this issue.

“This is not a normal time that we’re in. Your eating will not look normal. And we need to cultivate some humor about our foibles and a lot of self compassion,” said Mary Anne Cohen, a psychotherapist, director of the New York Center for Eating Disorders, and author of the new book “Treating the Eating Disorder Self.”

“Food is the safest, most available, cheapest mood-altering drug on the market,” Cohen said. “It soothes and comforts us when we’re stressed, and for lot of us that’s right now.” Cooking and eating, she said, “is an attempt to find resilience, to find meaning.”

How much of it is happening is so far hard to measure, except anecdotally from Zoom brownie-baking and ravioli-making get-togethers and endless Instagram posts of fresh-baked bread and meals. And, of course, not everyone is gorging on an overabundance of food; the economic fallout from the crisis has food banks reporting record demand.

But there are a few suggestions of the extent to which people who can afford it have returned in particular to baking.

Maine-based Stonewall Kitchens sold 11 times more baking mixes in March than in March of last year, a spokesman said. The Home Baking Association reports its Web traffic up by 150 percent; recipes requested the most are for sourdough bread, breakfast bars, and homemade pizza. Panhandle Milling Brands has seen the number of people sharing its recipes on Facebook increase 1,245 percent.

Whether people are eating all of that stuff they’re baking does concern nutrition and health experts. So do several other aspects of the shutdown.

The isolation of telecommuting provides the perfect cover for binge-eating, for example. As bars have closed, more people are drinking at home — off-premises sales of alcoholic beverages were up 55 percent in March, Nielsen reports — increasing calories and decreasing inhibitions about consuming even more junk food.

Boredom is also driving eating. “It’s almost a way to pass the time,” said Naidoo, who is also a chef and an instructor at the Cambridge School of Culinary Arts.

And all of this is happening at the same time that it’s harder to exercise consistently, which is exacerbating people’s weight gain.

Nearly a quarter of Americans said in a survey by ExerciseBike that they’re exercising less often and for less time, and a third that they were enjoying it less. “If you typically go to a yoga class, it might not be the same to take it online,” said Ziskind. “Without those things it’s a lot easier for people to go to the fridge and not exercise.”

And, oh, that refrigerator. On top of everything else, “with a lot of people working at home, there’s a ready availability of food,” said Brewer. “We don’t have our refrigerator right in front of us at work.”

When it’s time to stock up again, the drastically changed experience of food shopping also has an impact. Bare shelves and the dystopian sight of fellow customers lined up in masks stir up the anxiety that restarts the cycle of indulgence.

It’s just like with illicit drugs, said Barry Sears, president of the Inflammation Research Foundation in Peabody and author of the Zone Diet book series: “One of the reasons people relapse is the anxiety.”

When shoppers see those empty shelves, “It’s almost like your survival impact kicks in, which is, ‘I’m going to need more food,’” said Naidoo. “And the next aisle is ice cream.”

Not everyone is getting fat. Baron Christopher Hanson, 49, a corporate consultant from South Carolina, moved back early to the house of close family friends in Gloucester where he and his wife usually spend their summers. The advantage: 26 acres of land that needed a lot of intensive manual labor. A 265-pound former rugby player, Hanson has lost 23 pounds so far, he said; his wife, 10 pounds.

“We’re so lucky to have this option,” he said. “But anyone can get physical if they put their mind to it. Anyone can find a set of stairs to climb, home dumbbells, or water jugs to curl.”

Back in Maynard, Karon now is learning how to make bread. “It seems to be the thing to do, and I’m home and I have the time to do it,” she said. Fresh-baked and carbohydrate-rich foods “make us feel comfortable and warm and loved. And because we can’t get that from being outside and with our friends, we have to make up for it somehow.”

Of her eating during these disruptions, she added: “I also know that it’s not normal. But while I am shoving a piece of birthday cake in my mouth, I think, it’s OK. This is not a normal time.”

That’s what Cohen, the eating disorders specialist, said too.

“I hear from people constantly, ‘I’m going to get fat, I’m going to get fat,’” she said. “I tell them, ‘Let’s just take stock of the gratitude we have. We’ll take it off when we all get back to normal. And if we’re all still alive, who cares?’”

Jon Marcus can be reached at jonmarcusboston@gmail.com.