Milk has a relatively low content of vitamin D particularly in the winter. Summer milk may have approximately 30 IU in each quart but in winter, the content falls very much below this level. The vitamin D level in milk may be raised by simply adding the milk a dispersible preparation of the vitamin.
Pasteurization of milk and sterilization of evaporate milk do not destroy vitamin D. Most of the milk consumed in the United States contains added vitamin D.
Adding vitamin D in milk