Study participants will take 2, 000 I.U. 's of vitamin D3, believed to be the form most easily used by the body.
试验参与者将服用2000国际单位的维生素d3,维生素d的这种形式被认为最容易为人体利用。
2
That's a problem, particularly when it comes to vitamin D. Federal guidelines recommend that children get 400 I.U. of the vitamin a day, equivalent to four 8 oz. glasses of milk.