The effect of calcium supplementation on bone loss in 32 controlled trials in postmenopausal women.
ABSTRACT In 32 controlled trials of calcium supplementation (700-2000 mg) in 3,169 postmenopausal women, mean bone loss in the controls was -1.07% p.a. and in the treated subjects -0.27% p.a. (P for difference <0.001). The effect was similar at all measured sites and at all doses of 700 mg or more but became weaker after 4 years.
We have reviewed 32 trials of calcium supplementation in 3,169 postmenopausal women.
We found 24 publications reporting 32 controlled trials lasting at least 1 year, which provided annual percentage changes in bone mass or density at one or more sites in the calcium-treated and control subjects.
The median calcium supplement was 1,000 mg, median duration of the trials 2 years and total number of sites measured 79. The average of the mean rates of change in bone mass or density was -1.07% p.a. (P < 0.001) in the controls and -0.27% p.a. (ns) in the treated subjects (P for difference < 0.001). The effect of calcium was much the same at all measured sites (forearm/hand, proximal femur, spine, and total body and others). Supplements of less than 700 mg were not effective, but there was no significant beneficial effect of higher doses. There was significantly faster bone loss at total calcium intakes below 1,150 mg than on intakes over 1,350 mg. The effect of calcium appeared to be lost after 4 years of treatment.
Calcium supplementation of about 1,000 mg daily has a significant preventive effect on bone loss in postmenopausal women for at least 4 years.
- SourceAvailable from: ncbi.nlm.nih.gov[Show abstract] [Hide abstract]
ABSTRACT: Osteoporosis is the index disease for calcium deficiency, just as rickets/osteomalacia is the index disease for vitamin D deficiency, but there is considerable overlap between them. The common explanation for this overlap is that hypovitaminosis D causes malabsorption of calcium which then causes secondary hyperparathyroidism and is effectively the same thing as calcium deficiency. This paradigm is incorrect. Hypovitaminosis D causes secondary hyperparathyroidism at serum calcidiol levels lower than 60 nmol/L long before it causes malabsorption of calcium because serum calcitriol (which controls calcium absorption) is maintained until serum calcidiol falls below 20 nmol/L. This secondary hyperparathyroidism, probably due to loss of a "calcaemic" action of vitamin D on bone first described in 1957, destroys bone and explains why vitamin D insufficiency is a risk factor for osteoporosis. Vitamin D thus plays a central role in the maintenance of the serum (ionised) calcium, which is more important to the organism than the preservation of the skeleton. Bone is sacrificed when absorbed dietary calcium does not match excretion through the skin, kidneys and bowel which is why calcium deficiency causes osteoporosis in experimental animals and, by implication, in humans.Nutrients 09/2010; 2(9):997-1004. DOI:10.3390/nu2090997 · 3.15 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Cosmos caudatus is a local plant which has antioxidant properties and contains high calcium. It is also reported to be able strengthen the bone. This report is an extension to previously published article in Evidence Based Complementary and Alternative Medicine (doi:10.1155/2012/817814). In this study, we determined the effectiveness of C. caudatus as an alternative treatment for osteoporosis due to post-menopause by looking at the dynamic paramaters of bone histomorphometry. Forty female Wistar rats were divided into four groups i.e.. sham operated, ovariectomized, ovariectomized treated with calcium 1% ad libitum and ovariectomized force-fed with 500 mg/kg C. caudatus extract. Treatment was given six days a week for eight weeks. Dynamic and cellular histomorphometry parameters were measured. C. caudatus increased double-labeled surface (dLS/BS), mineral appositional rate (MAR), osteoid volume (OV/BV) and osteoblast surface (Ob.S/BS). C. caudatus also gave better results compared to calcium 1% in the osteoid volume (OV/BV) parameter. C. caudatus at the 500 mg/kg dose may be an alternative treatment in restoring bone damage that may occur in post-menopausal women.BMC Research Notes 06/2013; 6(1):239. DOI:10.1186/1756-0500-6-239
- [Show abstract] [Hide abstract]
ABSTRACT: Association between bone mineral density and bone mineral content in old age and milk consumption in adolescence, midlife, and old age was assessed. The association was strongest for milk consumption in midlife: those drinking milk daily or more often had higher bone mineral density and content in old age than those drinking milk seldom or never. The role of lifelong milk consumption for bone mineral density (BMD) and bone mineral content (BMC) in old age is not clear. Here we assess the association between hip BMD and BMC in old age and milk consumption in adolescence, midlife, and current old age. Participants of the Age, Gene/Environment Susceptibility-Reykjavik Study, aged 66-96 years (N = 4,797), reported retrospective milk intake during adolescence and midlife as well as in current old age, using a validated food frequency questionnaire. BMC of femoral neck and trochanteric area was measured by volumetric quantitative computed tomography and BMD obtained. Association was assessed using linear regression models. Differences in BMC, bone volume, and BMD in relation to milk intake were portrayed as gender-specific Z-scores. Men consuming milk ≥ once/day during midlife had 0.21 higher Z-scores for BMD and 0.18 for BMC in femoral neck (95 % confidence interval 0.05-0.39 and 0.01-0.35, respectively) compared with < once/week. Results were comparable for trochanter. For women the results were similar, with slightly lower differences according to midlife milk consumption. For current and adolescent milk consumption, differences in Z-scores were smaller and only reached statistical significance in the case of BMD for current consumption in men, while this association was less pronounced for BMC. Our data suggest that regular milk consumption throughout life, from adolescence to old age, is associated with higher BMC and BMD in old age, with no differences seen in bone volume. The strongest associations are seen for midlife milk consumption in both genders.Osteoporosis International 08/2013; 25(2). DOI:10.1007/s00198-013-2476-5 · 4.17 Impact Factor