很早以前,已经发现佝偻病是一种维生素 D 缺乏病。在十七世纪,英国已有不少的调查和实验资料记载人口稠密的城市居住区和烟尘弥漫的工业区,婴幼儿的佝偻病患病率很高,这说明阳光不足容易罹患佝偻病。近年来研究表明,在通常的气候条件 A long time ago, rickets was found to be a vitamin D deficiency. In the seventeenth century, many surveys and experimental data in the United Kingdom have documented densely populated urban settlements and smoggy industrial areas. The incidence of rickets in infants and young children is high, which shows that the sun is not prone to rickets. In recent years, research shows that under normal climatic conditions