Bone health and calcium absorption.
Well studied
Photo: Mike Art Visual CreatorDrag to turn · 28 heavy atoms · PubChem CID 5280795
Cholecalciferol (D3). Drag to turn it.
What the research says
Vitamin D is needed for bone health and normal calcium handling. In a large trial of generally healthy older adults, 2,000 IU a day did not lower fracture risk, and supplements have not been shown to lower cancer incidence.
Very high intakes can cause high blood calcium, and vitamin D may interact with statins, steroids, thiazide diuretics and orlistat.
About "most pills": Dose used in the VITAL trial described in the NIH ODS fact sheet (50 mcg a day); ODS also reports 400 to 2,000 IU a day in cancer trials.
Sources: ods.od.nih.gov
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