Search kind
Summary
Goal To look at the proof underpinning suggestions to extend calcium consumption by dietary sources or calcium dietary supplements to forestall fractures.
Design Systematic evaluate of randomised managed trials and observational research of calcium consumption with fracture as an endpoint. Outcomes from trials have been pooled with random results meta-analyses.
Knowledge sources Ovid Medline, Embase, PubMed, and references from related systematic critiques. Preliminary searches undertaken in July 2013 and up to date in September 2014.
Eligibility standards for choosing research Randomised managed trials or cohort research of dietary calcium, milk or dairy consumption, or calcium dietary supplements (with or with out vitamin D) with fracture as an end result and individuals aged >50.
Outcomes There have been solely two eligible randomised managed trials of dietary sources of calcium (n=262), however 50 reviews from 44 cohort research of relations between dietary calcium (n=37), milk (n=14), or dairy consumption (n=8) and fracture outcomes. For dietary calcium, most research reported no affiliation between calcium consumption and fracture (14/22 for complete, 17/21 for hip, 7/8 for vertebral, and 5/7 for forearm fracture). For milk (25/28) and dairy consumption (11/13), most research additionally reported no associations. In 26 randomised managed trials, calcium dietary supplements lowered the danger of complete fracture (20 research, n=58 573; relative threat 0.89, 95% confidence interval 0.81 to 0.96) and vertebral fracture (12 research, n=48 967. 0.86, 0.74 to 1.00) however not hip (13 research, n=56 648; 0.95, 0.76 to 1.18) or forearm fracture (eight research, n=51 775; 0.96, 0.85 to 1.09). Funnel plot inspection and Egger’s regression prompt bias towards calcium dietary supplements within the printed information. In randomised managed trials at lowest threat of bias (4 research, n=44 505), there was no impact on threat of fracture at any website. Outcomes have been related for trials of calcium monotherapy and co-administered calcium and vitamin D. Just one trial in frail aged ladies in residential care with low dietary calcium consumption and vitamin D concentrations confirmed important reductions in threat of fracture.
Conclusions Dietary calcium consumption just isn’t related to threat of fracture, and there’s no medical trial proof that rising calcium consumption from dietary sources prevents fractures. Proof that calcium dietary supplements stop fractures is weak and inconsistent.
Introduction
Older women and men are beneficial to take at the least 1000-1200 mg/day of calcium for bone well being and prevention of fractures.1 The typical consumption within the food regimen in Western international locations is 700-900 mg/day, and decrease in Asia and Africa, which means that the majority older individuals would want to take calcium dietary supplements to satisfy these suggestions. These pointers for calcium consumption have been broadly carried out, and, in some Western international locations, greater than 30-50% of older ladies take calcium dietary supplements.2 3 4 5 Medical trials of calcium dietary supplements at doses of 1000 mg/day, nevertheless, have reported opposed results, together with cardiovascular occasions,6 7 8 kidney stones,9 and hospital admissions for acute gastrointestinal signs.10 Consequently, older individuals have been inspired to enhance bone well being by rising their calcium consumption by meals slightly than by taking dietary supplements.11 This recommendation assumes that rising dietary calcium consumption to the beneficial stage of >1200 mg/day prevents fractures with out inflicting the opposed results of calcium dietary supplements.
We assessed the proof supporting the advice to extend dietary calcium consumption to forestall fractures and in contrast the anti-fracture efficacy of accelerating calcium consumption by dietary sources with the anti-fracture efficacy of calcium dietary supplements. We undertook a scientific evaluate of research of dietary sources of calcium or calcium dietary supplements in older adults (>50) with fracture as an endpoint. We primarily centered on the outcomes of randomised managed trials, however when inadequate proof from such trials was out there, we thought of outcomes of observational research.
Strategies
Outcomes – “calcium j”
Dialogue
There’s inadequate proof to evaluate the impact of accelerating calcium consumption within the food regimen from randomised managed trials as solely two small trials of dietary sources of calcium have reported fracture outcomes. Some 42 cohort research, nevertheless, have assessed relation between dietary calcium consumption, milk or dairy consumption and fracture. Most analyses (≥75%) discovered no associations, and the place there have been relations reported, most relative dangers have been between 0.5 and a couple of.0, that are thought of weak associations in observational research.72 The beneficial dietary calcium consumption for older adults is 1200 mg/day.1 Most research, nevertheless, didn’t report lowered threat of fracture in people with this stage of calcium consumption in contrast with decrease intakes. Thus, observational analysis doesn’t assist a speculation of dietary “calcium deficiency” during which there are reductions in fracture threat from rising dietary calcium consumption throughout the vary of intakes (<300->1200 mg/day) in research on this evaluate.
In 26 randomised managed trials, calcium dietary supplements lowered the danger of complete fracture by 11% and vertebral fracture by 14% however had no impact on forearm or hip fracture. The outcomes, nevertheless, weren’t constant. There was no impact of calcium dietary supplements on any fracture end result within the largest trials at lowest threat of bias. Just one trial in frail aged ladies in residential care with low dietary calcium consumption and vitamin D concentrations confirmed important reductions in fracture threat. Funnel plots have been additionally uneven with extra small-moderate sized research than anticipated reporting threat reductions in complete, vertebral, and forearm fracture with calcium dietary supplements, elevating the potential of publication bias. Outcomes from randomised managed trials of calcium monotherapy have been just like these with CaD, with no proof of further advantage of vitamin D on threat. These outcomes counsel that widespread untargeted use of calcium dietary supplements in older people is unlikely to end in significant reductions in incidence of fracture.
Notes
Cite this as: BMJ 2015;351:h4580