Analysis of anthropometric growth trends and prevalence of abnormal body status in Tainan elementary-school children.

Abstract

Objectives of this study were to examine the prevalence of over/underweight or obesity in Chinese children and investigate the trend of anthropometric change through the years. Cross-sectional measurements on randomly selected 6,373 Tainan elementary-school children were conducted in 1997. Anthropometric parameters such as height, weight, body mass index (BMI), triceps skinfold thickness (TSF), mid-arm circumference (MAC) and body-fat percentage (%FAT) were measured. Girls and boys had an average of 4.8 cm and 5.1 cm, or 3.7% and 3.9% increase in height, and 5.5 kg, 6.2 kg, or 19.9% and 22.2% increase in weight when compared to data of nationwide survey in 1986-88. If the height and weight were compared to the data of nationwide survey in 1993-1996, Tainan girls and boys would have similar height but have averaged 3.4% and 4.7% heavier weight. Mean BMI reached 19.4 kg/m2 for girls and 19.6 kg/m2 for boys of age 12 to 13. Mean %FAT of girls was 24.3% and of boys was 23.7%. When using weight-for-length index (WLI) larger than 1.2, mean weight exceeding 120% of age-and-sex specific mean weight, %FAT exceeding 30% to evaluate prevalence of obesity, results would be 42.1%, 17% and 22.0% respectively. In conclusion, both sexes had faster growth in weight than in height in recent 10 years. Boys had significantly higher weight, WLI, BMI, MAC than girls, while girls had significantly higher TSF and %FAT than boys. Prevalence of obesity is highly method-dependent. Appropriate index and cutoff values need to be developed.