Abstract

OBJECTIVE
This study sought to determine which components of youths' diets were related to adiposity while controlling for potential often-neglected confounders such as moderate to vigorous physical activity (MVPA) and dietary reporting error. Secondary goals of this study were to determine the extent to which MVPA confounded the associations between diet and adiposity and whether associations between diet and adiposity would differ depending on reporting error.
METHODS
An ethnically diverse urban sample of 342 children aged 9-10 years and 323 adolescents aged 17-18 years were recruited for this cross-sectional study. Body mass index (BMI) and waist circumference (WC) were measured in the school; dietary assessment included three 24-hour recalls via telephone in the evenings, and MVPA assessment included 5 days of accelerometry. Over (n = 68), under (n = 250), or plausible (n = 347) dietary intake reporters were identified with the Huang calculation method. Linear regression assessed the relationship between adiposity indicators (BMI z-score and WC) and components of the diet (energy intake, food groups, macronutrients) after controlling for reporting error, demographic variables, and MVPA.
RESULTS
When dietary reporting error and potential confounders such as MVPA and demographic variables were controlled, energy intake (EI), vegetables, refined grains, total fat, total protein, and total carbohydrate were positively related to BMI z-score and WC and artificially sweetened beverages to WC. MVPA was a significant confounder. For BMI z-score, but not WC, relationships and strength of these relationships differed depending on dietary reporting error group (plausible, underreporter, overreporter).
CONCLUSIONS
Among plausible reporters, as expected, EI, refined grains, and all macronutrients were positively related to adiposity; however, artificially sweetened beverages and vegetables, which are low-energy-dense foods, were also positively related to adiposity. Reporting error interfered with associations between diet and BMI z-score but not WC, suggesting WC is a more robust measure of adiposity in relation to diet.

Links

Publisher Full Text

Authors

Ledoux TA, Watson K, Barnett A, Nguyen NT, Baranowski JC, Baranowski T

Institution

Children's Nutrition Research Center USDA/ARS, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA. TALedoux@uh.edu

Source

Journal of the American College of Nutrition 30:6 2011 Dec pg 536-46

MeSH

Adiposity
Adolescent
Body Mass Index
Child
Cluster Analysis
Cross-Sectional Studies
Diet
Dietary Carbohydrates
Dietary Fats
Energy Intake
Exercise
Female
Humans
Linear Models
Male
Nutrition Assessment
Sweetening Agents
Waist Circumference

Pub Type(s)

Journal Article
Research Support, N.I.H., Extramural
Research Support, U.S. Gov't, Non-P.H.S.

Language

eng

PubMed ID

22331689