维生素A是小儿生长发育必需的营养素,其缺乏可直接影响小儿的体格生长。近年研究发现,维生素A还具有调节人体免疫和铁代谢等多种功能,维生素A缺乏的小儿患病率及病死率均明显升高。目前,严重维生素A缺乏虽已逐渐减少,但亚临床型维生素A缺乏仍普遍存在,对发达国家也不例外,它无典型临床表现,对人体健康、尤其时不断生长发育的小儿有不良影响,目前尚无单一有效的诊断指标,故对其诊断、防治等方面的深入研究具有重要意义。 Vitamin A is an essential nutrient for children’s growth and development, the lack of which can directly affect the physical growth of children. In recent years, studies have found that vitamin A also has a variety of functions to regulate human immunity and iron metabolism, vitamin A deficiency in children prevalence and mortality were significantly higher. At present, severe vitamin A deficiency has gradually decreased, but the lack of subclinical vitamin A is still widespread in developed countries is no exception, it has no typical clinical manifestations of human health, especially when the growth and development of children have an adverse impact, So far there is no single effective diagnostic index, so it is of great significance for its in-depth study on diagnosis, prevention and treatment.