Cholecalciferol Supplementation throughout Winter Does Not Affect Markers of Bone Turnover in Healthy Young and Elderly Adults

Abstract

Although there have been several studies of the effect of vitamin D status on bone turnover in the elderly, the findings are unclear, and, furthermore, to date very few have investigated this in young adults. The objective of these randomized, placebo-controlled, double-blind, 2-center intervention studies was to investigate the effect of cholecalciferol supplementation (0, 5, 10, and 15 microg cholecalciferol/d) throughout winter time on indices of vitamin D status and bone turnover in young (aged 20-40 y; n = 215) and elderly (aged > or = 64 y; n = 204) adults, with relatively high mean calcium intakes of 976 and 874 mg/d, respectively. Fasting serum concentrations of 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH), osteocalcin, bone-specific alkaline phosphatase, and carboxyterminal collagen crosslinks were measured by enzyme immunoassays at baseline and endpoint. Fok I and Taq I vitamin D receptor (VDR) genotypes were determined by real-time PCR. Endpoint serum 25(OH)D increased (P < 0.0001) in a dose-related manner with increasing supplemental cholecalciferol (up to 15 microg/d) in 20-40-y olds and up to 10 microg/d in > or = 64-y olds. Endpoint serum PTH was lower (P < 0.05) in the 3 cholecalciferol-supplemented groups compared with that in the placebo group in > or = 64-y olds, but cholecalciferol supplementation did not affect other markers in either cohort and there was no significant interaction with VDR genotype. In conclusion, cholecalciferol supplementation alone throughout winter did not affect bone turnover markers in apparently healthy young and elderly adults, even when stratified by VDR genotype.

Physical performance and life quality in postmenopausal women supplemented with vitamin D: a two-year prospective study

“…Hurst et al [26] found that women who were deficient in vitamin D and who were administered 4000 IU of cholecalciferol daily for 6 months exhibited a suppression of age-induced bone turnover and bone resorption. However, our results did not indicate that cholecalciferol supplementation had any effect on the levels of bone turnover markers, which is consistent with data from previous studies [21,27] . These results might have occurred because the participants in our study received inadequate doses of vitamin D supplementation.…”

Suboptimal effect of different vitamin D3 supplementations and doses adapted to baseline serum 25(OH)D on achieved 25(OH)D levels in patients with a recent fracture: a prospective observational study

“…However, based on the multivariate analysis, this dose-effect response was mainly explained by the baseline serum 25(OH)D and not the higher supplementation dose itself. In several studies, it has been reported that a higher vitamin D supplementation dose resulted in higher serum 25(OH)D levels (16,17,18,19). However, in contrast to our study, the effect of different supplementation doses was investigated in subjects with 25(OH)D levels O50 nmol/l and in groups with equal baseline 25(OH)D levels.…”

Comparison of the effects of cholecalciferol and calcitriol on calcium metabolism and bone turnover in Chinese postmenopausal women with vitamin D insufficiency

“…Kuwabara et al [21] discovered that the supplementation of 200 mg of calcium with 800 IU of vitamin D 3 daily for one month significantly lowered the serum PTH levels compared with the supplementation of only 200 mg of calcium daily. Seemans et al [17] identified that in the winter, the endpoint serum PTH level to be significantly lower in 3 cholecalciferol-supplemented groups (cholecalciferol 200 IU, 400 IU, and 600 IU) compared with the placebo group, though other bone turnover markers were not affected. An increased rate of bone turnover is associated with low bone mass [22] and an increased risk of bone fracture [23] .…”

“…Hurst et al [16] has shown that vitamin D-deficient women who were administered 4000 IU of cholecalciferol daily for 6 months displayed a suppression of age-induced bone turnover and bone resorption. However, some studies have shown cholecalciferol supplementation have no effect on bone turnover markers [17,21] . Oral vitamin D supplementation increases bone mineral density and appears to reduce the risk of hip and other nonvertebral fractures.…”

“…Hurst et al [16] concluded that correcting vitamin D deficiency in older women may suppress the age-induced acceleration in bone turnover and may reduce bone resorption. However, Seemans et al [17] observed that despite the stratification of different vitamin D receptor genotypes, cholecalciferol supplementation throughout the winter months did not affect bone turnover markers in young or old people. The aim of the current study was to compare the effects of cholecalciferol at 800 IU per day and calcitriol at 0.25 μg per day on calcium metabolism and bone turnover in Chinese postmenopausal women who are vitamin D insufficient.…”