School of Kinesiology and Recreation, Illinois State University, Normal, Illinois 61790, USA.
Am J Prev Med. 2011 Oct;41(4 Suppl 2):S93-9. doi: 10.1016/j.amepre.2011.07.003.
Few studies have identified health-related criterion standards of percent body fat (%BF) in U.S. youth. Further, existing standards are static thresholds (e.g., 25%, 30%) and do not account for normal growth and maturation.
The purpose of this study was to identify thresholds of %BF in youth linked to metabolic syndrome in a large sample of U.S. children and adolescents.
Percent fat was derived from the skinfold thicknesses of those aged 12-18 years, from the National Health and Nutrition Examination Survey (NHANES [1999-2004, N=1966]). Metabolic syndrome was classified using previously published standards based on the National Cholesterol Education Program/Adult Treatment Panel III adult values at age 20 years. Using %BF z-scores as the test and metabolic syndrome as the criterion, receiver operating characteristic (ROC) curve analysis was used to identify %BF thresholds.
ROC analysis indicated that %BF can be used with moderate accuracy to identify metabolic syndrome in adolescents. %BF thresholds of 22.3% and 35.1% in boys and 31.4% and 38.6% in girls (at age 18 years) were found to be indicative of "low" and "high" metabolic syndrome risk.
Age- and gender-specific %BF thresholds for creating separate risk groups were identified in relation to metabolic syndrome status. The selected thresholds identify adolescents with unfavorable metabolic profiles. These values could be extrapolated to younger children using previously created %BF centiles, which potentially allows for earlier identification and intervention of at-risk youth if tracking of current %BF was maintained.
很少有研究确定美国年轻人体脂肪百分比（%BF）的健康相关标准。此外，现有的标准是静态阈值（例如，25%、30%），没有考虑到正常的生长和成熟。
本研究的目的是在大量美国儿童和青少年中确定与代谢综合征相关的 %BF 阈值。
使用 1999-2004 年全国健康和营养检查调查（NHANES）中年龄在 12-18 岁的个体的皮褶厚度来计算体脂百分比。代谢综合征采用先前发表的标准进行分类，这些标准基于 20 岁时国家胆固醇教育计划/成人治疗小组 III 成人值。使用 %BF z 分数作为检验，代谢综合征作为标准，使用接收者操作特征（ROC）曲线分析来确定 %BF 阈值。
ROC 分析表明，%BF 可以中等准确度识别青少年的代谢综合征。在男孩中，22.3%和 35.1%，在女孩中，31.4%和 38.6%（在 18 岁时）的 %BF 阈值被发现与“低”和“高”代谢综合征风险相关。
确定了与代谢综合征状态相关的特定年龄和性别 %BF 阈值，以创建单独的风险组。选择的阈值可识别具有不利代谢特征的青少年。如果保持当前 %BF 的跟踪，可以使用先前创建的 %BF 百分位数推断出这些值在年幼的儿童中，从而有可能更早地识别和干预处于危险中的青少年。
