The Calculus of Calories: Mathematical Modeling of Body Weight Dynamics

Everybody knows that body weight change occurs when there is an imbalance between calories eaten and expended. But quantifying this relationship has been difficult since diet changes lead to complex adaptations that alter metabolism and body composition. Recently, we have developed several mathematical models to predict what happens when people of varying weights, diets, and exercise habits try to change their weight. Our models vary in their degree of physiological detail, with some incorporating the complex interactions between carbohydrate, fat, and protein metabolism and others focusing on energy imbalance. Our models have been used to illuminate the metabolic physiology underlying body composition regulation, predict the results of human obesity research studies, design and track the progress of clinical weight loss programs, and understand the dynamic origins of the obesity epidemic.