Research - Development and Prevention of Childhood Obesity
Behavioral Pathways of Biological Influences on Energy Balance
Obesity has reached record proportions in the US. Although increases may have leveled off among adults, obesity is still very common. Existing obesity prevention interventions generally have not worked, in part because the models of psychosocial influences (that provide the foundation for such interventions) on the relevant dietary and physical activity behaviors have had limited predictiveness. This project plan attempts to identify the extent to which genetic influences on dietary and physical activity behaviors are mediated by experiential variables (e.g., hunger, satiety, pleasure/enjoyment of physical activity) among late elementary school students. This is important because these experiences can be integrated into existing models of psychosocial influences on dietary and physical activity behaviors and enhances their predictiveness. Late elementary school is a time when the risk of becoming an obese adult, based on child obesity status, is highest. This study will generate models of how known genes may be influencing diet and physical activity practices and use this as a framework to identify likely experiential variables for which new questionnaires will be generated. These measures will feed into a larger study that will collect behavioral, psychosocial, the new experiential, and genetic variables to understand their interrelationships and influences on adiposity. Genes related to satiety or physical activity signaling pathways will be examined for association to eating and physical activity experiences. These data will facilitate the testing of complex models of the influences on adiposity, and thereby provide the foundation for designing effective behavior change interventions targeting known behaviors mediating weight changes.
Prevention of Childhood Obesity through Lifestyle Changes
The long-term objective of this project is to increase our understanding of how to prevent childhood obesity through targeted community interventions. A multifactorial theoretical approach based on Social Cognitive Theory (SCT) and parenting theory will be taken to address the built environment as well as family dynamics and child behavior at the community and primary care level. A 12-month family-based randomized controlled trial (RCT) will be conducted to test the effectiveness of diet behavior modification, structured aerobic exercise, or diet behavior modification plus structured aerobic exercise for obesity prevention and improvement in fitness, health risks, and psychological state in at-risk Hispanic children (Objective 1). The role of genetic variation in response to strategies aimed at diet and physical activity (PA) will be evaluated and a model developed to predict the obligatory changes in energy intake and physical activity level (PAL) required for obesity prevention. Family-centered intervention strategies will be developed and evaluated for the pediatric primary care setting to prevent childhood obesity (Objective 2). A conceptual model will be developed and formative work performed to evaluate the model for obesity prevention program for primary care clinics. A parent-targeted obesity prevention program will be developed and a pilot study conducted in pediatric primary care clinics. A RCT will be conducted to evaluate the parent-targeted prevention program for effectiveness in pediatric primary care clinics. Together, these strategies form a new paradigm that integrates community resources and pediatric primary care in support of the child and the family in the prevention and management of childhood obesity.
Web-based and Multi-Media Interventions to Promote Healthy Eating and Physical Activity in Families and Youth
Childhood obesity is a major public health problem in the U.S. and successful interventions to prevent obesity are needed. However, most existing obesity prevention intervention approaches have been found to be largely ineffective. Novel methods are needed. Web-based and multi-media technologies offer alternative means for educating youth on healthy dietary and physical activity behaviors, which are essential components of energy balance and, thus, obesity prevention. However, these strategies must be guided by theory-informed models of youth behaviors and evaluated by validated measures. This research will develop and/or test two innovative interventions. It will also evaluate and refine a model and measures of youth physical activity behavior and validate a measure of youth physical activity problem solving ability. The first objective will involve developing a website to promote healthy eating and activity behaviors for high school youth. The second objective will evaluate a 10-session videogame and a corresponding parent/guardian website to promote fruit and vegetable consumption to elementary age youth; it will also evaluate and refine a model and measures of youth physical activity behavior and validate a measure of youth physical activity problem solving ability. This research plan should substantially expand our knowledge base on how to utilize technology to promote healthy theory-informed dietary and physical activity behaviors. Understanding how to do this will ultimately contribute to the knowledge base regarding the design of effective interventions to reduce obesity and chronic disease risk. It will also provide a theoretical model and validated scales to guide future intervention research in this area.
Feeding Patterns, Dietary Intake, and Childhood Overweight in Diverse Ethnic Groups
The prevalence of overweight in preschool children has more than doubled in the past two decades. Currently, a third of children in the United States are at risk of overweight, while 17% are overweight. Because of these alarming statistics, a model of obesity-related eating behaviors influencing child weight status is urgently needed. The long-term goal of this project is to develop a model of relevant functional relationships of factors that influence the weight status of children. To accomplish this, various parent and child characteristics will be examined individually and in combination to determine their contributions to the problem of pediatric obesity. Specifically we will examine how different arrays of strategies used and problems encountered in feeding children healthy foods (in conjunction with feeding styles) influence children’s eating behaviors and, in turn, influence children’s weight status. We propose to examine both the direct effects of each factor as well as the transmitted effect through more proximal intervening processes that also have an influence on children’s weight status. Rather than examining this as a monolithic process that functions uniformly, we will attempt to refine the model by employing both dyadic and mixture modeling approaches to account for the latent heterogeneity in how these factors are functionally inter-related within the population.
Understanding Environmental Factors and Behavioral Changes for Childhood Obesity Prevention
Obesity among children has reached epidemic proportions. Today, an estimated one in four children in the United States is over weight (BMI above 85th percentile) and 11% are obese (BMI above 95th percentile). Overweight children tend to remain overweight during follow-up periods of up to 20 years, and in general, have a 1.5- to 2-fold increased risk for being overweight adults. Obesity in early life is associated cross-sectionally with several risk factors for coronary heart disease and is predictive of coronary heart disease, hypertension, and diabetes in adulthood. Obesity is the result of energy imbalance. Hence, to understand and prevent obesity both dietary and physical activity behavior, their determinants, and their direct and indirect associations with overweight need to be examined. Theory-based programs targeting dietary and physical activity behaviors have had limited success. This may be due to invalid theoretical assumptions, inadequate program components, and/or poor measures of outcomes and mechanisms of change. To effectively combat obesity in children and youth, it is important to identify and help address these potential sources of problems. Consequently, one of the goals of this project is to assess the validity of current theories of obesity-related behavior change by conducting mediating variable analyses (analyses of mechanisms of influence) using extant datasets. Another goal of this project is to identify new determinants of obesity. In this respect, while both nutrients and individual foods have been assessed for evaluation of their association with obesity, few attempts have been made to identify a broader eating pattern, which may be associated with obesity. It is intuitive that changes in eating patterns may explain the increased obesity, since foods are generally not eaten in isolation, and the overall pattern of a diet may have more of an impact on obesity than any one food or nutrient. Consequently, this project will aim to identify environmental factors and eating pattern “typologies” associated with diet quality and obesity in children, adolescents, and young adults using extant datasets.