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Green means go, red means stop. Trophies or confetti come with good performance, and people who fall behind get nudged to do better.
Those brightly colored engagement tactics long ago jumped from smartphone games to everything from online shopping to sports betting and classrooms. So it should come as no surprise that many nutrition-tracking apps like MyFitnessPal and Noom also use gaming features to keep users coming back.
But as nutrition apps proliferate, some researchers are raising alarms that gamification features may do more harm than good for some people.
Isabella Anderberg, a psychologist researching digital dieting behavior at Flinders University in Adelaide, Australia, said calorie tracking can reinforce behaviors associated with body dysmorphia and disordered eating.
“We do know that not everyone’s going to experience harm from using the apps, but there are certainly factors that might increase risk,” Anderberg said. “Approach with caution.”
The case for nutrition tracking apps
Anderberg said there is certainly a place for the apps. Health professionals she interviewed during her research reported that apps can be especially helpful as meal-planning tools for people managing chronic conditions such as heart disease and diabetes. And physical activity apps remind people to move their bodies.
Many users report enjoying them, finding tactics like streak notifications to be motivating.
Angela Drury, an English professor in Woodstock, Georgia, began using MyFitnessPal more than 10 years ago to track protein, fat, carbohydrate and calorie intake when she started CrossFit. She has since cycled through several other apps, including Weight Watchers, Lose It and now Nourish, which is paid for by her insurance and includes blood work and weekly meetings with a dietitian.
Drury said the apps have helped her stay on track with fitness goals and have sometimes steered her away from high-calorie foods when she uploaded photos of meals she was considering eating. She feels a little boost when she gets a badge for continuing a streak for logging meals, but a notification that says she hasn’t entered lunch has the opposite effect.
“Then it felt like it was scolding me,” she said.
Be wary of what the app tells you
The way most apps work, users enter height, weight, age and other information and then set a goal. The app says how many calories or macronutrients are needed to reach that goal, using gamelike elements such as badges, streaks, rewards, points and notifications to encourage user engagement.
Many nutrition tracking apps are free but offer premium versions that users must pay for.
The Centers for Disease Control and others say that how many calories you need depends on factors including your age, sex and level of physical activity. The CDC provides a tool to calculate how many calories an individual needs.
