[Evidence for efficacy of active vitamin D3 as an anti-osteoporotic drug].

Active vitamin D3 has been most widely used in Japan for the treatment of osteoporosis. Although it mildly increases bone mineral density, it has little consistent effect on bone metabolic markers, and clinical evidence for its efficacy as a fracture-preventing drug is rather weak. Recent reports suggest that (active) vitamin D3 may prevent fracture incidence not only by promoting intestinal calcium absorption but also by improving neuromuscular function to reduce the number of falls.