The effect of personalised weight feedback on weight loss and health behaviours: Evidence from a regression discontinuity design.

Abstract

Using a regression-discontinuity approach on a U.K. longitudinal dataset, this research analyses whether personalised weight feedback resulted in individuals losing weight over a period of between 2 and 7years. The analysis presented here finds that being told one was "overweight" had, on average, no effect on subsequent weight loss; however, being told one was "very overweight" resulted in individuals losing, on average, approximately 1% of their bodyweight. The effect of feedback was found to be strongly moderated by household income, with those in higher income households accounting for seemingly all of the estimated effect due, in part, to increased physical activity. These findings suggest that the provision of weight feedback may be a cost-effective way to reduce obesity in adults. They do however also highlight that the differential response to the provision of health information may be a driver of health inequalities and that the provision of feedback may bias longitudinal health studies.