Are Fitness Trackers Worth it?

A JAMA study has found that among young adults attempting to lose weight, adding a wearable device that tracks exercise and energy expenditure offers no benefit over a standard weight-loss intervention. The results are surprising, given the increased popularity of wearable technology and the growing notion that diary-making and accountability are key components to an effective weight-loss regimen.

In the study, 470 overweight or obese young adults were randomized to a standard or enhanced weight-loss intervention. All participants received a behavioral intervention that included calorie reduction, physical activity prescription and group counseling.

Only after six months did participants in the enhanced intervention group also begin wearing a sensor that tracked physical activity and offered feedback on energy expenditure. The standard intervention group simply monitored their diet and activity on a website, also beginning at the six-month mark.

What’s interesting about this study is that the researchers attempted to isolate the fitness tracker variable specifically, not the monitoring of diet and activity that is generally thought to be important to weight loss plans.

At 24 months, the enhanced intervention group had lost significantly less weight than the standard intervention group. The fitness trackers lost just under 8 lbs on average, compared to 13 lbs on average for the standard group. Curiously, neither physical activity nor diet differed significantly between the groups during the study.

The study authors write: “Among young adults with a BMI between 25 and less than 40, the addition of a wearable technology device to a standard behavioral intervention resulted in less weight loss over 24 months. Devices that monitor and provide feedback on physical activity may not offer an advantage over standard behavioral weight loss approaches.”

Clearly more research is needed to determine what mechanisms might be at play here. But for now, if you’re reluctant to spend the money on a wearable fitness tracker, take solace in the fact that good old fashioned diary keeping appears to be as, or indeed more, effective in keeping you on your game.

JAMA, 2016, Vol. 316, No. 11, pp. 1161-1171,

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