Human growth and body weight dynamics: an integrative systems model

Area of Science:

• Human physiology
• Biomedical modeling
• Public health

Background:

• Accurate quantification of human weight and height dynamics is crucial for clinical practice and policy.
• Existing models often lack a comprehensive, life-span approach to body composition and growth.
• Understanding energy balance is key to addressing issues from malnutrition to obesity.

Purpose of the Study:

• To present the first mechanism-based model that spans an individual's full life.
• To capture dynamic changes in body weight, composition, and height.
• To provide a tool for diverse policy and clinical applications.

Main Methods:

• Development of a novel mechanism-based model integrating empirical and prior modeling findings.
• Validation of the model against multiple additional empirical studies.
• Simulation of key human growth trends and energy balance dynamics.

Main Results:

• The model successfully replicates critical human growth trends, including energy requirement changes from birth to old age.
• It captures short- and long-term dynamics of body weight and composition.
• It simulates stunted growth from malnutrition and potential for catch-up growth, and quantifies energy surplus in obesity.

Conclusions:

• The developed model offers a versatile tool for analyzing diverse policy questions, from obesity to malnutrition.
• It highlights embedded energy intake surpluses contributing to obesity inertia.
• The model and accompanying simulation tools are freely available for customized applications.