The Sneaky Way ‘Fitness’ Foods Sabotage Your Weight Loss

They may seem healthy enough, but could fitness-branded foods be hurting your weight-loss efforts? (Photo: Sara Stathas/Alamy) 

An energy bar or stash of trail mix can be a lifesaver on a long bike ride, a hilly hike, or a day full of dashing from one errand to another. But if you’re trying to lose weight, watch out for a sneaky side effect: Without even realizing it, people tend to eat more and exercise less when a food is branded to promote fitness, according to a new study published in the Journal of Marketing Research.

In the study, half of the 162 participants received a bag of trail mix labeled simply “Trail mix snack,” while the other half were given the same mix, but with a label that said “Fitness snack” and showed a picture of running shoes. They were told they were taking part in a taste test, but actually, researchers were measuring how much trail mix they ate.

Overall, there wasn’t a significant difference between the two groups. But among people who were watching their weight and restricting their calories, participants given the fitness-labeled snack ate significantly more of it than weight-watchers who were given the regular trail mix. And the more someone was restricting his or her eating, the more food the person was likely to consume. People with the highest score on a diet restriction questionnaire ate approximately 200 more calories of the “Fitness snack” trail mix than the regular kind.

“Fitness-cued foods are compatible with restrained eaters’ long-term goals,” says study author Joerg Koenigstorfer, PhD, professor of sport and health management at Technische Universität München in Munich, Germany. “The claims reduce the conflict between eating enjoyment and weight control. This compatibility absolves restrained eaters from having to watch their weight and licenses them to pursue the eating enjoyment goal.” As a result of eating for pleasure and ignoring their weight-loss goals, Koenigstorfer tells Yahoo Health, dieters end up overeating fitness-branded foods.

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Fitness labeling can also affect how much a person chooses to exercise, the study discovered. In a separate experiment, Koenigstorfer and colleagues asked 144 students to eat trail mix with a fitness label, diet label, or no label. Then the students were told to cycle on a stationary bike “as hard as you want and feel like at the moment.”

The results: Weight-conscious students burned fewer calories on the bike when they were served the fitness-branded snack, compared with the unlabeled snack. But the opposite was true for people who weren’t watching their weight: They actually burned more calories on the bike when given the fitness-labeled trail mix.

“One may have expected that restrained eaters would be more physically active in the presence of fitness-branded food; however, we show that the opposite is true,” Koenigstorfer tells Yahoo Health. “Eating fitness-branded food compensates for actual physical activity in restrained eaters.”

Related: 10K Steps Per Day Might Not Get You Fit

Previous research has shown that people tend to consume more calories when a food has a healthy-sounding label, a phenomenon known as the “health halo.” For example, a study from Cornell University found that people estimate that organic cookies and chips have fewer calories than nonorganic versions.

What’s the fix? First, listen to your body’s signals, Koenigstorfer advises. Patricia Bannan, RD, author of Eat Right When Time Is Tight, recommends rating your hunger on a 1-to-10 scale before and after you eat. “You should start eating when you’re starting to feel hungry but you’re not famished,” Bannan tells Yahoo Health. “Once you get famished, it’s kind of too late in terms of your choices.” Afterward, you should feel satisfied but not uncomfortably stuffed, she adds.

In addition, be sure to check the nutrition label and be aware when a food is high in calories. (Many fitness-branded foods are, since they’re designed to fuel you through exercise.) “This is even more important given consumers’ tendencies to underestimate calorie content,” Koenigstorfer says.

In terms of physical activity, Bannan says, it’s important to see exercise as a part of a healthy lifestyle — not just a way to burn calories to lose weight. “Labeling can really throw you off if you don’t have more of a holistic understanding that, even if it’s healthy food, you still want to eat the amount that nourishes your body, and you still want to be physically active,” she says, instead of “just thinking, ‘It says all-natural or it says gluten-free, and I can eat as much as I want.’”

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