Does sharing health data help maintain weight loss?

Researchers studied 87 adult participants in a 12-month weight loss program. For the entire study participants were asked to complete three self-monitoring activities daily -- wear a Fitbit fitness tracker, weigh themselves on a wireless scale and log their food intake in a smartphone app.

All participants started with a weekly group session to learn behavioral skills during the first three months of the study. After the third month, the group sessions ended. From that point through the end of the study -- known as the maintenance phase -- each participant received just one weekly text message and one monthly phone call with their coach.

"This is the period that is often hard for folks who want to lose weight," said Meghan Butryn, PhD, lead author of the study, associate professor in the College of Arts and Sciences and director of Research in the WELL Center. "And weight that is initially lost tends to start to be regained."

During the maintenance phase, participants were randomized so that half of them worked with a coach who had access to their self-monitoring data. The coach addressed the data during the phone calls and text messages. For the other half of participants, the coaches could not see data from the Fitbit, wireless scale or digital food record.

Coaches shared what they observed from participants' self-monitoring data about changes in eating habits, weight and physical activity, and helped participants evaluate the extent to which they met their goals. For example, in a phone call a counselor might say, "You set a goal last month of five bouts of exercise per week, and I see that you only averaged two per week. Tell me more about what happened."

Researchers said that although the study was small, the pattern suggests that when coaches had access to data, it helped participants keep off their weight.

"We were interested to see if weight-loss maintenance would be better when coaches could see the data and provide feedback and a sense of accountability to participants, which might help sustain a high level of motivation to keep up healthy eating behaviors and physical activity," said Butryn.

Butryn added that this is spurring additional research that considers questions about the effectiveness of supportive accountability such as: If your primary care doctor was able to see all of your Fitbit exercise data, would it motivate you to be more physically active?