alorie counts, already present on many restaurant menus, may be required at chain restaurants nationwide if the Food and Drug Administration gets its way. (A rule the FDA passed to that effect has been stalled by Congress.) But it’s an open question whether such labeling has the intended effect of nudging people toward healthier meals.
“Economist skeptics like me say, ‘No way,'” said researcher Partha Deb, professor of economics at Hunter College. “My gut instinct was that we weren’t going to find anything. I mean, when I go to McDonald’s with my kid, we just get what we’re going to get no matter what the calories.”
But Deb and colleagues turned to the data to find an answer. And they discovered that calorie labeling does appear to improve the health of overweight and obese people.
Researchers compared the body mass index (BMI) of people living in places with calorie-labeling laws — including Maine, Massachusetts, Oregon, and California — to those with no such laws, from 2003 to 2012. Researchers also looked at average BMI before and after enactment of calorie-labeling laws.
They found virtually no change in the BMI for people of normal weight. But overweight and obese individuals in places with calorie-labeling laws did alter their behaviors. Overweight women reduced their BMI by an average of .9 percent; the drop was 1.4 percent for overweight men. Obese women, strangely, saw no change, but obese men dropped their BMIs by 2 percent. The study was published by the National Bureau of Economic Research.
“I was surprised to find such substantial reductions,” said Deb. “We’re seeing that the labeling is pretty powerful.”
The study has some limitations. “Their samples were urban, not rural,” said Tina Colaizzo-Anas, director of dietitian education at Buffalo State University, who was not involved with the study. Also, she pointed out, “there’s no data on the frequency with which people eat outside the home. Or the proximity of grocery stores.”
Deb admits that the results need a closer look beyond statistical analysis.
“I can see why people might not change their actions the instant they see a sign,” he said. “But maybe they don’t come back to McDonald’s as often, or maybe they don’t have their heart set on that high-calorie meal next time. Maybe exercise is a factor. Looking into all of that is probably the next step.”