Haven’t studies demonstrated that calcium and vitamin D has no effect on fractures?

The Women’s Health Initiative, which investigated the benefits of calcium and vitamin D supplementation in 36,282 postmenopausal women aged 50 to 79, demonstrated that supplementation could reduce the incidence of hip fracture in post-menopausal women by about 20 percent. Further, a recently-published metanalysis has confirmed that supplementation with both calcium and vitamin D reduces the risk of hip fracture(Boonen et al. J of Clin End & Meta 2007;92(4):1415-23).

Both calcium and vitamin D supplements are essential components of an integrated management strategy for the prevention and treatment of osteoporosis.