Causes of vitamin D deficiency include intestinal malabsorption which can be seen with celiac disease or Crohn's disease, not enough UV light exposure, like in homebound, elderly populations.

引起维生素D缺乏的因素包括：小肠吸收不良，可见于乳糜泻和克罗恩病；紫外线照射不足，常见于久居家中的老年人。