Losing weight and elimination of weight cycling by the geometric approach to global-stability problem

In the process of losing weight, the weight cycling, i.e., repeated bouts of the weight loss and regaining, can usually happen and be harmful to human. Thus it is very important to search for its mechanism, and more important is to keep the weight fixed and avoid weight cycling. Based on the recent developments, a geometric approach to global-stability problems is employed to obtain the conditions for the global asymptotic stability of the equilibrium in the human weight cycling model. The conditions are obtained to keep the weight stable without cycling. It means that, even though the food intake QQ is large, if the metabolic efficiency aa is sufficiently small, then the weight cycling will be avoided and the aim to lose weight can be achieved. The above theoretical results are validated by employing the nonlinear dynamics software—WinPP.