What is the psychological impact of self-weighing? A meta-analysis

Many people self-weigh and many interventions addressing weight-related problems such as obesity promote self-weighing. However, while self-weighing has been associated with weight loss, there is mixed evidence regarding the psychological impact of this behaviour. The present review aimed to quantify the relationship between self-weighing and: (i) affect (e.g., anxiety, depression); (ii) psychological functioning (e.g., self-esteem); (iii) body-related attitudes and (iv) disordered eating. A computerized search of scientific databases in September 2014 and subsequent ancestry and citation searches identified 29 independent tests of the relationship between self-weighing on psychological outcomes. Meta-analysis was used to quantify the size of the association across the tests. Results indicated that there was no association between self-weighing and affect, body-related attitudes or disordered eating. There was, however, a small-sized negative association between self-weighing and psychological functioning. The age of participants, obesity status, the extent of weight loss, duration of self-weighing and study design (RCT versus correlational) were found to influence at least some of the psychological outcomes of self-weighing. The findings suggest that, for the most part, self-weighing is not associated with adverse psychological outcomes. However, in some cases the association between self-weighing and psychological outcomes may be more negative than in others.