Wearable fitness trackers, from Fitbit to Mi Band and many more, are incredibly popular. Several smartphone apps act as a fitness tracker as well, using just the movement of a phone to calculate calories burned and steps taken. We have covered a few of these apps and several studies looking at the efficacy of such trackers in the past. Such apps and devices have been used to increase activity, lose weight, improve fatigue, manage stress, and even to help guide clinical decision making.
Still, not all the data for such trackers has shown such a positive result. The results from a recent randomized controlled trial on fitness trackers for weight loss have just been published the September Journal of the American Medical Association. The study, titled “Effect of Wearable Technology Combined With a Lifestyle Intervention on Long-term Weight Loss: The IDEA Randomized Clinical Trial” noted less weight loss in patients who relied on activity trackers rather than a standard weight loss program! This study has been widely covered throughout major media outlets and has thrown a little water onto the mobile health tracker fire.
Let’s take a closer look at the IDEA study. With a total 471 adult participants, researchers at the University of Pittsburgh evaluated the use of wearable devices throughout a weight loss program. All participants were put on a low-calorie diet, provided group counseling, and given prescriptions for physical activity. At 6 months into the program, they were roughly split into two groups: a control that simply did self-monitoring of diet and exercise through a website, and an interventional group that utilized the website and a wearable activity tracker (FitCore by BodyMedia). Both groups received reminder text messages about weight loss during this period. Primary outcome measure was weight loss after 24 months, with secondary outcomes including body composition, cardiorespiratory fitness, dietary intake and several other measurements. Patients had a BMI between 25 to less than 40, and tended to be young adults.
Results noted only 3.5kg in the intervention activity tracker group, with actually greater weight loss in the control group of 5.9kg! The groups also had similar improvements in secondary outcomes, without a clinically significant difference between them. The authors concluded that activity monitors may not offer much of an advantage over traditional weight loss therapy.
It’s hard to say exactly why this well-designed study showed such a poor outcome for wearable activity trackers. It could be argued that participants in the intervention wing may have relied too heavily on the activity tracking alone, were discouraged when not meeting tracking goals, or justified less activity levels based on their daily metrics.
Alternatively, there may be a selective patient population that best benefits from such technology, and wasn’t captured within this large study. In particular, the kind of therapy that the control group isn’t something that’s readily available to all patients or feasible for those that do have access. It could be argued these kinds of digital health interventions best serve patients who can’t access these more intensive, in-person behavioral interventions.
Still, such data, over a 2 year study, can’t be ignored, and will hopefully spur further investigation into the best approach for using such health trackers in weight loss.