The role of nutrient partitioning and stem cell differentiation in pediatric obesity: a new theory

Abstract

It is commonly theorized that some youths become fatter than others simply because they eat too much and exercise too little; i.e., they have an excessive positive energy balance. This theory suggests that obesity prevention efforts should emphasize dietary strategies designed to reduce energy intake, with moderate physical activity (PA) playing a supporting role. However, such interventions have typically been unsuccessful, perhaps because pediatric research that has measured body fatness, rather than weight, has found that the simple energy balance theory is faulty; it is critical to also consider whether the ingested energy is deposited in fat or lean tissue in order to provide a more complete picture of the etiology of pediatric obesity. In some way that is still poorly understood; vigorous PA and mechanical stimulation of the body stimulate stem cells to differentiate into bone and muscle rather than fat, with the result that ingested nutrients tend to be partitioned into lean tissue rather than fat. Thus, active youths tend to ingest more energy than their sedentary peers without increasing the percentage of the body mass that is comprised of fat tissue. Having a high level of both energy expenditure and intake is in accord with the biologic drives of youths because it encourages them to ingest sufficient amounts of the nutrients needed for healthy growth. Thus, public health interventions are likely to be more effective if they devote more attention to increasing PA and less attention to dietary strategies designed to reduce energy intake.

Cardiorespiratory Fitness as a Mediator of the Influence of Diet on Obesity in Children

“…Since fitness has been shown in several reviews to be very related to high-intensity physical activity [ 15 , 16 , 37 ], our results could be partially explained by the theory proposed by Gutin [ 38 ], in which the amount of physical activity by young children is a potent predictive factor of their fat and lean tissue. Physical activity stimulates physiologic processes that conduct nutrient intake to be partitioned in muscle and bone instead of adipose tissue.…”

Pathways for Disordered Eating Behaviors in Minority Girls

“…Previous research has used proxy measures of adiposity (e.g., BMI) rather than a direct, objective measure. The use of BMI to determine body adiposity in children and adolescents is problematic because BMI only considers body weight relative to height, and thus, does not differentiate between fat-free mass and fat mass (Deurenberg, Yap, Wang, Lin, & Shmidt, 1999; Gutin, 2011). However, percent body fat is able to assess the actual fat mass of an individual.…”

Body Image Disturbances and Predictors of Body Dissatisfaction Among Hispanic and White Preadolescents

“…Although the authors of this study used BMI in combination with %BF to predict BD, the inclusion of BMI estimation to assess body size in school‐aged populations is problematic. Specifically, BMI only considers body weight relative to height and thus does not differentiate between fat‐free mass and fat mass (Gutin, ). Furthermore, this study did not take into consideration interindividual and gender variation in sexual maturation rates which are related to children's and adolescents' views of their physical bodies.…”