2012 Annual Report
1a.Objectives (from AD-416):
Objective 1: Identify risk factors, moderators, and mediators for obesity and obesity-related behaviors, including dietary, physical activity, and lifestyle factors using extant datasets.
Sub-objective 1A: Determine differences in diet quality among obese, overweight, and normal weight children among a nationally representative sample.
Sub-objective 1B: Examine walking or biking to school, objective physical activity, and weight status in adolescents.
Sub-objective 1C: Examine the association of television viewing (TV) with source of food, eating occasion, and portion size.
Sub-objective 1D: Determine associations between objectively measured physical activity and markers of insulin resistance and cardiovascular disease in US children and adolescents.
Sub-objective 1E: Determine the relationship between dietary energy density, obesity, and the metabolic syndrome among adolescents.
1b.Approach (from AD-416):
We will conduct cross-sectional data analyses of National Health and Nutrition Examination Survey (NHANES) and will focus on the following: diet quality, active commuting to school, television and video viewing, physical activity, and dietary energy density among nationally representative samples of US youth to determine associations with obesity and related disorders. We will identify potential dietary underreporting by using gender and age group specific cutoffs for reported energy intake as a percentage of predicted energy requirements as previously developed by USDA funded research. We will use linear/logistic regression analyses and stratify by socio-demographics to determine the highest at-risk groups for poor diet quality. Since Healthy Eating Index (HEI)-2005 assesses diets on a per 1000 calorie basis, it will not be necessary to control for diet quantity or energy intake for these analyses. To identify potential socio-demographic disparities in the association between moderate to vigorous physical activity and markers of insulin resistance and cardiovascular disease, interactions with gender, race/ethnicity, and income will be examined.
The overall project objective was to conduct analyses using the National Health and Nutrition Examination Survey administered by the US Centers for Disease Control and Prevention or other databases to identify risk factors, moderators, and mediators of childhood obesity. Among US youth ages 6-19 years, we examined the relationship between physical activity and clinical risk factors for heart disease and diabetes. Lower amounts of moderate-to-vigorous physical activity were associated with higher waist circumferences and greater risk for heart disease and diabetes. A manuscript of this work was published in Metabolic Syndrome and Related Disorders. We revised analyses examining the association between children’s adiposity and their diet quality, as measured by the USDA’s Healthy Eating Index-2005. Preliminary analyses showed that greater BMI and waist circumference were associated with lower diet quality. A revised manuscript is in process and the work will be submitted for peer-review at a biomedical journal. We have downloaded the NHANES data and have begun analyses of children’s television viewing and associations with fast food, snacks, and portion sizes. However, in order to estimate portion sizes, we need to link the NHANES database with the corresponding USDA MyPyramid equivalents database (MPED). Since we are including NHANES 2005-2006 data, we need to wait for the release of MPED 3.0, which will be applicable for use with NHANES 2005-2006 data. We anticipate the release will occur in the next year. If the MPED 3.0 release does not occur in a timely fashion, we will drop NHANES 2005-2006 data and use older releases instead, or use a different suitable database, including site visits and review of annual accomplishment reports.