Modelling body weight, dieting and obesity traps

This paper presents a theoretical investigation into why losing weight is so difficult even in the absence of rational addiction, time-inconsistent preferences or bounded rationality. We add to the existing literature by focusing on the role that individual metabolism has on weight loss. The results from the theoretical model provide multiple steady states and a threshold revealing a situation of “obesity traps” that the individual must surpass in order to successfully lose weight. Any weight-loss efforts that the individual undertakes have to surpass such threshold in order to result in permanent weight loss, otherwise the individual will gradually regain weight and converge to his or her previous body weight.