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Vitamin D insufficiency: disease or no disease?
Karen E Hansen1, Andrea N Jones, Mary J Lindstrom
1Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792, USA. keh@medicine.wisc.edu
Abstract:
Vitamin D insufficiency (VDI) is widely reported. In patients with normal PTH, the diagnosis rests on increases in fractional calcium absorption (FCA) when 25(OH)D increases above 30 ng/ml. However, estimates of increased FCA after correction of VDI vary dramatically, depending on study methods. We used a dual stable calcium isotope to clarify the impact of vitamin D repletion on FCA in postmenopausal women with VDI. We hypothesized that FCA would increase with vitamin D repletion. We studied postmenopausal women with VDI [25(OH)D = 16-24 ng/ml] and an estimated calcium intake
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