Think your Fitbit is helping you lose weight? Turns out, wearable activity trackers may hinder your diet, according to the American Medical Association.
In a study funded by the National Heart, Lung and Blood Institute, dieters wearing activity monitors lost an average of 7.7 pounds over the span of two years, compared to the average 13-pound loss of tech-free participants. The 5.3-pound difference surprised researchers, as the study was meant to prove the effectiveness of fitness trackers.
"Activity monitors started coming onto the market in a commercial sense in the early 2000s, but they've really picked up steam in the last couple of years," said John Jakicic, the lead author of the study, “We went in with the hypothesis that adding the technology would be more effective than not having the technology, and we found just the opposite,”
The study focused on 470 adults ages 18-35 with a body-mass index (BMI) of 25 to 39. According to the National Institutes of Health, a BMI of 25 to 29.9 is “overweight” and a BMI of 30 or greater is “obese.” The participants were divided into two random groups – one with activity monitors and one without. They then participated in face-to-face counseling on weight loss. Over the course of 24 months, participants were taught the basics on nutrition and exercise, and were encouraged to track their activity on a website. Jakicic, a professor of the Physical Activity and Weight Management Research Center at the University of Pittsburgh, based the weight loss program on behavioral theory.
"We find those to be the most effective way to deliver these programs and cost-effective way to deliver these programs," added Jakicic.
Weekly group sessions were offered to participants for the first six months. For the rest of the study, participants had monthly group check-ins, monthly phone check-ins and weekly text messages.
While participants with fitness trackers lost less weight than those without, Jakicic notes that both groups improved their body composition, physical activity and eating habits.
“One of the things we didn’t study here was, maybe these things are really effective for people gaining weight, but maybe that’s different from helping people lose weight,” said Jakicic.
Although the results showed that fitness trackers stalled weight loss, the study was not able to fully conclude why it hindered the process.
"Anecdotally, these devices tend to work or people tend to engage with them for about three months or so, and after that, a lot of people start throwing them in the drawer. They get bored with them," Jakicic said.
Dr. Barbara Berkeley, who did not partake in the study, suggested the problem might have to do with participants’ reward systems.
“It's entirely possible that those who were paying more attention to the exercise part of their regimen [because of the wearable device] were less scrupulous about their intake," Berkeley said, “Exercising [often causes dieters to] feel that they've 'earned' the chance to eat more.”
Berkeley also suggested that dieting could be more important in weight loss, with exercise as a weight maintenance strategy.
Jakicic said he’s looking forward to analyzing the reason behind the study’s unexpected results.