More than 90 percent of black children had low blood leels of itamin D, and about a fifth had readings associated with rickets and other diseases of the bones or muscles.

• 超过90%25的黑色人种儿童呈现低水平的维生素D，其中大约五分之一发生佝偻病以及其他一些肌肉、骨骼疾病。