By Linda Carroll

(Reuters Health) – Consumers might make healthier choices if food labels showed how many minutes of walking or running was needed to burn off calories, instead of just a calorie number, a new study suggests.

Pooled data from 14 randomized trials showed that labels with activity times induced consumers to cut back nearly 65 calories per meal more than labels that simply listed calories, researchers reported in the Journal of Epidemiology & Community Health.

Labels with “physical activity calorie equivalent or expenditure,” or PACE, were illustrated with drawings of a runner and a walker, each accompanied by an estimate of how many minutes would be needed in that activity to burn off the calories in the labeled food.

“The PACE food labeling, where you show how many minutes of physical activity are required to expend the calories in a food may be a good way of helping the public make healthier food decisions and reduce overall calorie consumption,” said the study’s lead author, Amanda Daley, a professor of behavioral medicine at Loughborough University in the UK.

“We know that the public underestimates the number of calories in food, so we need to find an easy method to make it easier for the public to make healthier decisions about what they eat,” Daley said in an email. “We think the public will understand this better than telling them how many calories are in a food item.”

To determine if the type of labeling makes a difference in consumer food choices, Daley and her colleagues scoured the medical literature for trials that compared PACE labeling to standard labels with just a calorie count or no calorie information at all.

The 14 studies they included in the current analysis “presented food or gave menus of food options to participants with and without PACE labeling, or the studies presented PACE labeling versus calories only or versus traffic light labeling,” Daley explained. “And they asked participants what they would like to eat for a snack or for lunch or dinner and so on.”

Daley’s team found that when PACE labeling was displayed on foods, drinks and menus, people consumed an average of 64.9 calories less per meal than when only calorie counts were displayed.

The PACE labeling is “a cool idea,” said Avigdor Arad, director of the Mount Sinai PhysioLab and an endocrinologist at Mount Sinai St. Luke’s in New York City. “But we don’t really have enough evidence to say whether it’s going to be effective. Certainly more trials are needed.”

Moreover, Arad said, the emphasis on calories might not be the best way to get people to eat healthier since there’s no information on food quality.

“Certain foods are nutrient dense and also calorie dense,” Arad said. “We don’t want people to develop a fear of consuming things like nuts, avocados, figs and certain legumes.”

Another potential problem is that the estimates of time running or walking might seem unrealistic to some people because the rates at which calories are burned depend on a number of factors, such as age, weight and fitness, Arad said. So people might be skeptical of the numbers on the labels, he added.

Still, Arad said, “it’s an idea worth exploring further.”

SOURCE: Journal of Epidemiology & Community Health, online December 10, 2019.