Why Food Labels That Specify How Much Exercise It Takes to Burn Calories Are a Bad Idea
The labels might contribute to disordered thinking about food and exercise.
At this point, calorie counts are commonplace on food packaging and restaurant menus. But new research has looked into another more aggressive approach: labeling foods with equivalent exercise that would burn their calories off. These physical activity calorie equivalent (PACE) labels might specify, for instance, how long you'd have to walk to burn the number of calories in a slice of cake. A recent scientific review published in the Journal of Epidemiology and Community Health suggests PACE labels might lead people to consume fewer calories, but that might be at a major cost. (Related: We Seriously Need to Stop Thinking of Foods As 'Good' and 'Bad')
Researchers looked at 15 existing studies that compared using PACE labeling on menus or food packaging to using other food labels or no labels at all. Based on the research, they found that, on average, people chose lower-calorie options when faced with PACE labels compared to people who didn't see the labels. There didn't seem to be a notable difference compared to traditional calorie labeling.
The Royal Society for Public Health in the UK already called for PACE labeling to be used on the front of food packaging in 2016. This study was meant to provide further clarity on how the labels affect people's behavior. Lead study author Amanda Daley argues that the results suggest PACE labels might be worth a shot. "The evidence shows that even a relatively small reduction in daily calorie intake (100 calories) combined with a sustained increase in physical activity is likely to be good for health and could help curb obesity at the population level," she stated in a press release. "PACE labeling may help people achieve this."
The intention behind PACE labeling is that it could give people a more concrete understanding of calories. It turns the unit of energy into a less abstract measurement–time spent exercising. PACE labeling "could be a useful tool to help the public understand what a calorie means and therefore more able to decide whether the calories are 'worth it,'" the study authors write. But that's a huge flaw with PACE labels.
Deciding whether a food is 'worth it' isn't just a matter of counting calories. It's important to eat the foods that'll sustain you through everyday tasks and any added activity. "It is possible for two different foods to have the same amount of calories while containing varying amounts of the essential nutrients your body needs to function properly day after day," Emily Kyle, M.S., R.D.N., C.D.N., previously told us. "If we are focusing solely on calories, we are missing out on the nutrients that matter the most."
That mindset can be harmful. "Labeling food as something that needs to be counteracted through exercise creates a dangerously instrumental view of food and physical activity that is a hallmark of disordered eating," says Christy Harrison R.D., C.D.N., author of upcoming book Anti Diet. "...In my clinical experience, and as I've seen in the scientific literature, breaking down food into calories to be negated through exercise sets many people on a harmful path toward compulsive exercise, restrictive eating, and often compensatory binge eating."
TL;DR: In her eyes, PACE labels would do more harm than good. (Related: What You Need to Know About the Latest Update to U.S. Nutrition Labels)
"Placing labels on food products with generalizations about how much activity may be required to burn the calories off reinforces the idea that exercise is simply a counterbalance for ingesting calories or that one should feel guilty for eating," says Kristin Wilson, M.A., L.P.C., vice president of clinical outreach for Newport Academy. "It can lead to increased anxiety around nutrition and health and can contribute to disordered thinking about eating and exercising. This can result in the manifestation of an eating disorder, exercise compulsion, and mood disorders." (See: What It Feels Like to Have Exercise Bulimia)
Beyond that, providing an exercise for a given food is an oversimplification of how your body functions, says Harrison. "The 'calories-in, calories-out' model fails to take into account the fact that different bodies use energy very differently," she says, "and that people's histories of dieting and deprivation can make their bodies far more efficient at storing energy." Metabolic rates and nutritional needs are "individualized and subject to change across the lifespan," echoes Wilson. (Related: Counting Calories Helped Me Lose Weight—But Then I Developed an Eating Disorder)
So while PACE labels might make people eat fewer calories, policymakers should consider the potential negative impacts that could last much longer than just one meal's length. There's no getting around the implications of suggesting food should be in some way canceled out through exercise.