Bone mass status of school-aged children in Taiwan assessed by quantitative ultrasound: the Nutrition and Health Survey in Taiwan Elementary School Children (NAHSIT Children 2001-2002).

Bone health status in childhood and adolescence may be important factors influencing the attainment of peak bone mass. The Nutrition and Health Survey in Taiwan Elementary School Children 2000-2001 was carried out to evaluate the overall nutrition and health status of school children aged between 6 and 13 years. The survey was conducted using a multi-stage complex sampling scheme. Townships and city districts in Taiwan were classified into 13 strata. Bone mass measured as broadband ultrasound attenuation was taken at heel by quantitative ultrasound bone densitometry. A total of 1164 boys and 1016 girls who had complete physical examination data with ultrasound bone scan were included in the current analysis. There were no apparent differences in BUA across all strata for both genders. In both boys and girls, age, height, body weight, BMI, and intake frequencies of vegetables and fruits/juices were significantly related to BUA. Results of multivariate regression showed that age (beta=1.36, p=0.0002) and body weight (beta=0.40, p<0.0001) were significant predictors for BUA in boys, whereas in girls body weight (beta=0.47, p<0.0001), height, (beta=0.20, p=0.01), dietary phosphorus intake (beta=-0.002, p=0.038), and frequency of fruit/juice intake (beta=0.15, p=0.029) remained statistically significant. The differential effects dietary intake variables on BUA in boys and girls may be in part due to the development of puberty. It would be necessary to include levels of physical activity in future analyses for better understanding factors influencing the development of peak bone mass in Taiwanese children.