Effect of withdrawal of calcium and vitamin D supplements on bone mass in elderly men and women

Background: Supplementation with calcium and vitamin D reduces bone loss an d prevents fractures in elderly people, but it is not known whether any las ting benefit remains if the supplements are discontinued. Objective: The objective was to determine whether gains in bone mineral den sity (BMD) induced by calcium and vitamin D supplementation persist after s upplement withdrawal. Design: Two-hundred ninety-five healthy, elderly men and women (aged greate r than or equal to 68 y) who had completed a 3-y randomized, placebo-contro lled trial of calcium and vitamin D supplementation were followed fur an ad ditional 2 y during which no study supplements were given. BMD was measured by dual-energy X-ray absorptiometry, and biochemical variables related to calcium metabolism and bone turnover were measured. Results: In the 128 men, supplement-induced increases in spinal and femoral neck BMD were lost within 2 y of supplement discontinuation, but small ben efits in total-body BMD remained. In the 167 women, there were no lasting b enefits in total-body BMD or at any bone site. Consistent with the observat ions on BMD, the bone turnover rates in both men and women (as measured by serum osteocalcin concentrations) returned to their original higher concent rations within the same 2-y period. Conclusion: Discontinued calcium and vitamin D supplementation has limited cumulative effect on bone mass in men and women aged greater than or equal to 68 y.