Some people might prefer not to know exactly how many calories are in a Starbucks Frappucino or Bloomin' Onion from Outback Steakhouse. Nevertheless, the Food and Drug Administration has required that the information be displayed on chain restaurant menus in the U.S. since 2018, and a similar rule was introduced in the U.K. in 2022.
But do calorie counts really change the way people eat? Evidence suggests they have a small but tangible impact, according to a new systematic review from the Cochrane Collaboration.
The review found that calorie labels prompt people to select foods with an average 1.8% fewer calories than they would without calorie labels -- the difference between a 600-calorie meal and a 589-calorie one.
That's not much. But small daily changes "can have meaningful effects if sustained long-term," Gareth Hollands, a co-author of the review and researcher at University College London, said in a press briefing. He cited a U.K. government report that found 90% of people between ages 20 and 40 in England gain up to 9 kilograms (roughly 20 pounds) over the course of a decade.
Cutting 24 calories a day would prevent that increase, Hollands said. "Many of us are able to benefit from some help to maintain weight by cutting small numbers of extra daily calories that explain a lot of population weight gain."
While the review is valuable, it's difficult to draw conclusions about the average effect of calorie labeling given the various types of studies included in the review, said Christina Roberto, an associate professor of health policy at the University of Pennsylvania's Perelman School of Medicine who has studied the impact of food labeling requirements and was not associated with the study.
But she agreed with the review's general conclusion that calorie labeling has some influence over consumer choices.
"I think it's kind of incredible that it works at all," Roberto said. "It's such a light touch intervention, it's just some numbers on a menu, it's incredibly cost-effective, and you do get these small reductions." For these reasons, she said, calorie labeling policies "feel like a no-brainer.
The Cochrane review included 25 studies on the effects of calorie labeling, including 16 that took place in restaurants, cafeterias, and supermarkets rather than labs. (All but one of the studies included in the meta-analyses focused on dining establishments; that study took place in a French supermarket, and looked at prepared foods, pastries, breads, and canned prepared meals like cooked beans.) Twenty-four of the studies were conducted in high-income countries like the U.S., the U.K., Ireland, France, and Canada. An earlier version of the review was published in 2018, and has now been updated to include more recent studies.
The review also found that calorie labels may lead people to eat smaller portions of the food they select -- about 5.9% less on average. But most of the studies on portions were conducted in labs, not in the real world, giving researchers low confidence in this conclusion.
Two studies included in the review focused on the effects of labels on alcoholic drinks, but the results were inconclusive. Most countries don't require nutrition labels on alcoholic beverages. In the U.S., the Alcohol and Tobacco Tax and Trade Bureau, which regulates most alcoholic products, is weighing updated rules on what information companies are required to disclose.
While restaurant chains have been required to post calorie counts on menus for six years in the U.S., some state and local governments introduced those requirements even earlier, including New York City in 2008 under former New York mayor Michael Bloomberg. (STAT's coverage of commercial determinants of health is funded by Bloomberg Philanthropies, but is editorially independent.) In the U.S., four out of five Americans say they regularly consult nutrition labels when deciding whether to buy an item, according to the most recent data from a U.S. Department of Agriculture survey. Labels have less influence over Americans when they go out to eat -- 43% said it swayed their decisions in fast-food and sit-down restaurants, according to the same survey.
The review shows calorie labeling works, according to Aviva Musicus, science director at the Center for Science in the Public Interest, which has long advocated for such policies. "Labeling is just one of the many tools that we need to employ to address our country's chronic disease crisis," she said. "But transparency through calorie labeling and other forms of labeling is an important first step for helping consumers get the information they need."
Experts including Hollands agreed that calorie labels are by no means a silver bullet. "These kinds of interventions would ideally be introduced alongside a broader set of approaches, including those that place more onus on industry rather than individuals," he said. Examples include taxes like the U.K.'s soft drinks levy and marketing restrictions like a U.K. rule that, starting in October 2025, will ban products high in fat, sugar, or salt from advertising on TV before 9 p.m. and completely ban online ads for those foods.
Regardless of how much calorie labels shape people's food choices, some health experts have argued in recent years that calories are the wrong metric to focus on when it comes to improving health.
"Calories are an outdated, outmoded, and, I would argue, a useless form of information to get people to eat healthier," said Giles Yeo, a geneticist at the University of Cambridge who focuses on the connections between genes, food intake, and obesity.
The problems with calorie labels are twofold, Yeo said. First, "when you're trying to compare different types of foods, it gives you nothing about the nutritional content of the food." When picking between, say, a burrito bowl and a BLT at a restaurant, information about the protein, fiber, fat, or sodium in each item would be more useful than calories in steering people toward healthy choices.
In a move tied to such concerns, the FDA this week proposed new labels on the front of packaged foods that would highlight the amount of saturated fat, added sugars, and sodium in one serving.
The other issue, Yeo said, is that calorie counts "target the worried well and not the people who need it the most, who are likely to buy cheap processed foods because that's what they can afford. We need to think how we can make healthy eating equitably available to all of society."