Objective: To describe the distribution of fat mass (FM), fat mass percentage (FMP), and fat mass index (FMI) in children aged 3-17 years in China. Methods: Data of this study were from the National Nutrition and Health Systematic Survey in 0-18 years old children in China. A total of 70 853 children aged 3-17 years old selected from seven regions of China were included in this analysis. Body composition were measured by using bioelectrical impedance meter. The region, gender and age specific FM, FMP and FMI of the subjects were described by using M (Q1,Q3). Kruskal-Wallis H rank sum test was used for the comparison of intergroup differences. DSCF method was used for pairwise comparisons. Results: The medians of FM, FMP and FMI were 3.0 kg, 18.3% and 2.9 kg/m2 in boys aged 3 years and 2.9 kg, 19.0% and 2.9 kg/m2 in girls aged 3 years, respectively. The FM increased with age and the FMP and FMI decreased with age in both boys and girls aged 3-5 years. After 11 years old, the FM, FMP and FMI decreased first and then increased in boys. From 6-17 years old, the FM, FMP and FMI increased gradually in girls. The FM, FMP and FMI were higher in girls than in boys after 12 years old (all P<0.05). The FM, FMP and FMI were relatively higher in children at the age of 6-14 in northeastern and northern China than in other regions. Conclusions: The age specific FM, FMP and FMI had different changing characteristics in boys and girls aged 3-17 years in seven regions of China. The FM, FMP and FMI also differed with region.
目的： 描述我国3~17岁儿童体脂质量（FM）、体脂百分比（FMP）和脂肪质量指数（FMI）分布特征。 方法： 数据来自中国0~18岁儿童营养与健康系统调查与应用项目，研究对象为我国7个地区3~17岁儿童70 853人，利用生物电阻抗仪测定调查对象体成分。采用M（Q1，Q3）描述不同地区、不同性别、不同年龄段儿童的FM、FMP和FMI分布特征。采用Kruskal-Wallis H秩和检验进行组间差异比较，采用DSCF法进行两两比较。 结果： 3岁男童的FM、FMP和FMI中位数分别为3.0 kg、18.3%和2.9 kg/m2，3岁女童的FM、FMP和FMI中位数分别为2.9 kg、19.0%和2.9 kg/m2。3~5岁男女童FM逐渐增加，FMP和FMI逐渐下降。11岁以后男童FM、FMP和FMI先下降后上升。6~17岁女童FM、FMP和FMI逐渐增加。12岁以后，女童的FM、FMP和FMI均高于男童（均P<0.05）。东北和华北地区男女童的FM、FMP和FMI在6~14岁相对较高。 结论： 我国7个地区3~17岁男女童FM、FMP和FMI在不同年龄段具有不同的变化特征，不同地区之间也存在一定差异。.