Cholecalciferol, found in fish oils, cod liver oil and is made in the skin.
Analogues include calcitriol and alfacalcidol which stimulate formation and activity of osteoblasts preventing bone loss and reduce risk of vertebral fractures.
Supplemental cholecalciferol 700-1000 IU/d reduces falls and non-vertebral fractures in community dwelling and institutionalized older individuals (Bischoff-F2242ari HA et al).
2000 IU/d of cholecalciferol reduces hospital readmissions but not falls in individuals after hip fracture (Bischoff-F2242ari HA et al).