Short and Long-Term Variations in Serum Calciotropic Hormones after a Single Very Large Dose of Ergocalciferol (Vitamin D2) or Cholecalciferol (Vitamin D3) in the Elderly.
There is always discussion over which form of Vit D is most effective. This study finds that D3 is twice as effective. In addition, it demonstrates the safety of a single dose of 300,000 IU given orally.
