学龄儿童维生素A营养状况及其与铁的相关性研究

为观察学龄儿童维生素A(VA)营养状况、亚临床VA缺乏患病率及VA与铁的相关性 ,对北京房山山区 1 0 1 2名 7～ 1 3岁学龄儿童进行膳食调查 ,随机抽取 30 5名儿童 ,静脉采血于避光下分离血清 ,用高效液相色谱法检测血清VA含量 ,同时测定其血清铁蛋白 (SF)、红细胞游离原卟啉 (FEP)和血红蛋白 (Hb) ,并依现行标准将其分为正常、铁缺乏 (ID)、红细胞生成缺铁期 (IDE)与缺铁性贫血 (IDA)四组 ,观察VA与铁的相关性。结果显示受检儿童膳食总能量、蛋白质和铁平均每日摄入量均达到膳食营养素的推荐摄入量 (RNI)及适宜摄入量 (AI) ,但平均每日VA摄入量为 (51 3 7± 2 86 1 ) μgRE ,仅占RNI的 59 7% ;血清VA平均含量为(1 0 1± 0 2 9) μmol L ,血清VA低于 1 0 5μmol L者占受检儿童的 59 0 % ,其中 1 2 8%的儿童血清VA低于0 70 μmol L ,正常及以上者仅占 41 0 %。并观察到血清VA含量与机体铁状况有相互随对方下降而减低的趋势。结果表明 ,该地区儿童存在明显的VA缺乏 ,应加强营养教育、改善不合理的膳食结构并通过适当的VA防治予以纠正

Study of vitamin A nutritional status and the correlation of vitamin A and iron in school-age children

To understand the VA status, the detectable rate of the sub-clinical VA deficiency and the correlation of VA and iron in the rural school-age children of Beijing Mountain Area. In the dietary survey, blood samples were collected by venopunction and serum VA, and hematological index were determined in 305 children 7-13 years. The intakes of dietary energy, protein and iron were > 85% of the RNI and AI, but dietary intake of VA were (513.7 +/- 286.1) microgram to be 59.7% of the RNI; The average concentration of serum VA was (1.01 +/- 0.29) mumol/L, 59.0% of subjects have serum VA lower than 1.05 mumol/L, in which, 12.8% of them were lower than 0.70 mumol/L, and only 41.0% of subjects were normal levels of serum. With aggravation of iron deficiency from ID to IDA phase, the average serum VA concentrations were descending from 1.02 mumol/L in ID phase to 0.97 mumol/L in IDA phase. But the trend has no statistical significance. The results showed that sub-clinical VA deficiency was 59.0% in the rural school-age children, so VA deficiency was a main nutritional problem in rural school-age children of Beijing mountain area.