Calcium and just 800 IU gave positive effect on skeleton  RCT Mar 2010
Effect of calcium and vitamin D supplementation on bone mineral density in women aged 65–71 years: a 3-year randomized population-based trial (OSTPRE-FPS)
Journal	Osteoporosis International  March 10, 2010
M. Kärkkäinen1 Contact Information, M. Tuppurainen1, 2, K. Salovaara1, 3, L. Sandini4, T. Rikkonen1, J. Sirola1, 3, R. Honkanen1, 5, J. Jurvelin6, E. Alhava7 and H. Kröger1, 3   {All Finland}

Received: 30 September 2009  Accepted: 10 December 2009  Published online: 4 March 2010
Summary  
The Osteoporosis Risk Factor and Prevention-Fracture Prevention Study (OSTPRE-FPS) was a randomized population-based open trial (n = 593). The supplementation group (n = 287) received daily cholecalciferol 800 IU + calcium 1,000 mg for 3 years while the control group (n = 306) received neither supplementation nor placebo. Daily vitamin D and calcium supplementation have a positive effect on the skeleton in ambulatory postmenopausal women.
Introduction  
Vitamin D deficiency is common in the elderly, and vitamin D levels are associated with low bone mineral density (BMD). The working hypothesis was that vitamin D and calcium supplementation could prevent bone loss in ambulatory postmenopausal women.
Methods  
The OSTPRE-FPS was a randomized population-based open trial with a 3-year follow-up in 3,432 women (aged 66 to 71 years). A randomly selected subsample of 593 subjects underwent BMD measurements. The supplementation group (n = 287) received daily cholecalciferol 800 IU + calcium 1,000 mg for 3 years while the control group (n = 306) received neither supplementation nor placebo.
Results  
In the intention-to-treat analysis, total body BMD (n = 362) increased significantly more in the intervention group than in the control group (0.84% vs. 0.19%, p = 0.011). The BMD change differences at the lumbar spine (p = 0.372), femoral neck (p = 0.188), trochanter (p = 0.085), and total proximal femur (p = 0.070) were statistically nonsignificant. Analyses in compliant women (≥80% of use) resulted in stronger and statistically significant effects at the total body and femoral regions.
Conclusion  
Daily vitamin D and calcium supplementation have a positive effect on the skeleton in ambulatory postmenopausal women with adequate nutritional calcium intake.