Diet quality as measured by the Diet Quality Index-International is associated with prospective changes in body fat among Canadian children

Abstract

Objective To quantify the association of dietary quality with prospective changes in adiposity. Design Children participating in the QUALITY (Quebec Adipose and Lifestyle InvesTigation in Youth) study underwent examination at baseline and at 2-year follow-up. Dietary quality was assessed by the Diet Quality Index-International (DQII) using three non-consecutive 24 h diet recalls at baseline. The DQII has four main categories: dietary adequacy, variety, moderation and overall balance. Fat mass index (FMI; [fat mass (kg)]/[height (m)]2), central FMI (CFMI; [trunk fat mass (kg)]/[height (m)]2), percentage body fat (%BF; [total fat mass (kg)]/[total mass (kg)]) and percentage central BF (%CBF; [trunk fat mass (kg)]/[total mass (kg)]) were assessed through dual-energy X-ray absorptiometry. Setting Children were selected from schools in the greater Montreal, Sherbrooke and Quebec City metropolitan areas between 2005 and 2008, Quebec, Canada. Subjects A total of 546 children aged 8-10 years, including 244 girls and 302 boys. Results Regression analysis adjusting for age, sex, energy intake, physical activity and Tanner stage revealed that every 10-unit improvement in overall DQII score was associated with lower gain in CFMI (β=-0·08; 95 % CI -0·17, -0·003) and %BF (β=-0·55; 95 % CI -1·08, -0·02). Each unit improvement in dietary adequacy score was associated with lower gain in FMI (β=-0·05; 95 % CI -0·08, -0·008), CFMI (β=-0·03; 95 % CI -0·05, -0·007), %BF (β=-0·15; 95 % CI -0·28, -0·03) and %CBF (β=-0·09; 95 % CI -0·15, -0·02). Conclusions Promotion of dietary quality and adequacy may reduce weight gain in childhood and prevent chronic diseases later in life.