[Association between dietary calcium/dairy intakes and overweight/obesity]

To investigate the intakes of dietary calcium/dairy and the current prevalence of overweight and obesity among children and adolescents aged 7-15 in Longquanyi District, Chengdu, and to explore the association of dietary calcium and dairy intake with overweight/obesity.

1738 children and adolescents were recruited in the cross-sectional study using cluster random sampling method. Information on dietary calcium and dairy intakes was collected using 24-hour dietary recall and food frequency questionnaire (FFQ). Height, weight and waist circumference were measured to calculate body mass index (BMI)/waist-to-height ratio (WHtR) and body mass index standard deviation (BMI SDS). Overweight/obesity was defined based on the criteria of Working Group on Obesity in China (WGOC). Participants were grouped into 3 categories indicating lower, moderate and higher intakes of dietary calcium and dairy, respectively. The association of dietary calcium and dairy consumption with (BMI SDS) /WHtR and the prevalence of overweight/obesity was analyzed after being stratified by gender and age.

The prevalence of overweight/obesity in boys and girls were 11.92%/7.04% and 8.04%/6.30%, respectively. The intake of dietary calcium and dairy in girls were much higher than that in boys (P < 0.0001). Among boys aged 7-9 years, those with higher consumption of dairy had the higher BMI SDS (P = 0.01). Among boys aged 10-12 years, those with higher consumption of dietary calcium had the lowest prevalence of overweight (P = 0.03). However, similar results were not observed among girls.

Dietary calcium and dairy intakes seemed to be related to overweight/ obesity in boys, however the associations were inconsistent among different age groups. Associations between consumption of calcium, dairy and overweight/obesity were not found among girls.