Feedback models allowing estimation of thresholds for self-promoting body weight gain.

Objective: Most people maintain almost constant body weight over long time with varying physical activity and food intake. This indicates the existence of a regulation that works well for most individuals. Yet some people develop obesity, indicating that this regulation sometimes fails.

Energy imbalance underlying the development of childhood obesity.

Objective: To develop a model based on empirical data and human energetics to predict the total energy cost of weight gain and obligatory increase in energy intake and/or decrease in physical activity level associated with weight gain in children and adolescents.

Research Methods And Procedures: One-year changes in weight and body composition and basal metabolic rate (BMR) were measured in 488 Hispanic children and adolescents. Fat-free mass (FFM) and fat mass (FM) were measured by DXA and BMR by calorimetry.

Quantitative analysis of the energy requirements for development of obesity.

Objective: Obesity is typically developed over long time and reflected in an energy imbalance, which is too small to be measured and controlled. Our objective is to formulate a mathematical model for the relation between the change in body mass and the values of the energy intake and the energy expenditure, controlled by the physical activity factor PAF. DATA AND THEORY: The uncontrolled components of energy expenditure increases as result of body mass increase: expenditure of a larger mass and expenditure to convert matter in intake into tissue.