维生素A的生物学作用及其缺乏的防治

维生素A在人体的视觉、免疫、生长发育及细胞分化等方面发挥广泛的、重要的生物学作用。尽管补充维生素A的公共卫生政策已广泛推行,但维生素A缺乏仍然是许多发展中国家（尤其是低收入国家或地区）面临的一个重要公共卫生问题。今后仍需积极探索更灵敏、准确、价廉、易推广的评价指标与方法和更好、更有效、可持续的综合干预措施,以更好评估目标人群存在的风险,并推进维生素A缺乏的防治。

Biological effects and its control of dificiency of Vitamin A

Vitamin A plays an important biological role in human vision,immunity,growth and differentiation of cells and so on.Despite massive Vitamin A supplementation public health policies in developing countries has been carried out,the burden of VAD is still common,especially in low income countries or regions.Future efforts should be maintained to better target populations at risk with more sensitive,accurate,cheap,feasible evaluation indexes and methods,and better,effective,sustainable integrated interventions approaches to promote prevention and treat ment of Vitamin A dificiency.