Since it’s inception circa 2007, Fitbit has not only become one of the most popular health and fitness devices ever, it ushered in a whole new market for activity trackers that eventually compelled big players such as Apple to make their own such devices.
Fitbit is a watch or bracelet like wristband and its primary purpose is to track your movement throughout the day and thereby how many calories you burn in doing so. There are several different models now, ranging from around $50 – $250, that offer a variety of different features such as GPS, heart rate monitoring, or even the ability to store and play music. Research also shows that these devices are now fairly accurate (ref).
But can such a device actually work for weight loss?
The underlying and driving hypothesis seems to be that by tracking and quantifying that data, it will motivate you to be more active than you would be otherwise and expend more calories, potentially lose weight, and improve your overall health and fitness.
The seemingly limited scientific research on this question appears to be mixed. One small short term study resulted in people wearing trackers increasing physical activity over a control group (ref), while another much larger and long term study resulted in people wearing trackers actually losing less weight than a control group (ref). A speculation for the latter result is that “[t]here is [a] psychological shift when [people] see calorie count or the amount of physical activity; they allow themselves to eat more because they have done some sort of physical activity,” according to one researcher who wasn’t part of the latter study but commented on it (ref). This is indeed but one of many reasons that weight loss strategies that solely focus on exercise, and thereby none on diet, tend to be ineffective.
Our take: don’t just buy a Fitbit and magically expect the weight to fall off. However, it’s fair to speculate that, for some, tracking that data might inspire a person to burn more daily calories, certainly so if you actually set a daily target for yourself. But the key is that this must be done with concurrent focus on diet, at the very least ensuring that it remains unchanged despite any new additional activity. That is what will create a meaningful change in the energy balance equation and cause weight loss.