Defining “success” in preventing or managing obesity is usually based on a measure of weight (kg), BMI (kg/m2, z-score, percentile), and/or body fatness/composition.These metrics can be measured reliably and accurately. They also reflect what many people (clinicians, patients, decision-makers) expect to be reported; plus, the equipment necessary to collect these kinds of data are available in most schools, public health units, and clinical settings.
However, as anyone who’s worked with children, adults, and families with obesity can attest, focusing on weight or weight status exclusively fails to consider the overall health of individuals and families. Success can and should be defined in ways that are meaningful to different groups. Finally, it is critical to avoid assumptions about weight and weight loss, a point that is emphasized very thoughtfully in a recent commentary in BMJ.