![Sample our Bioscience journals, sign in here to start your access, Latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5925/TOC-Subject-Sample-2021-Bioscience.jpg"})
Abstract
Osteoporosis is a multifactorial disorder in which nutrition plays a role but does not account for the totality of the problem. 139 papers published since 1975 and describing studies of the relationship of calcium intake and bone health are briefly analyzed. Of 52 investigator-controlled calcium intervention studies, all but two showed better bone balance at high intakes, or greater bone gain during growth, or reduced bone loss in the elderly, or reduced fracture risk. This evidence firmly establishes that high calcium intakes promote bone health. Additionally, three-fourths of 86 observational studies were also positive, indicating that the causal link established in investigator-controlled trials can be found in free-living subjects as well. The principal reason for failure to find an association in observational studies is the weakness of the methods available for estimating long-term calcium intake. While most of the investigator-controlled studies used calcium supplements, six used dairy sources of calcium; all were positive. Most of the observational studies were based on dairy calcium also, since at the time the studies were done, higher calcium intakes meant higher dairy intakes. All studies evaluating the issue reported substantial augmentation of the osteoprotective effect of estrogen by high calcium intakes. Discussion is provided in regard to the multifactorial complexity of osteoporotic response to interventions and to the perturbing effect in controlled trials of the bone remodeling transient, as well as about how inferences can validly be drawn from the various study types represented in this compilation.
Key teaching points:
• A very large body of evidence establishes that high calcium intakes augment bone gain during growth, retard age-related bone loss, and reduce osteoporotic fracture risk.
• Dairy sources of calcium are at least as efficacious in this respect as are calcium supplements.
• The protein and sodium contents of dairy foods do not adversely affect the bone benefit of the dairy package of calcium, phosphorus, protein, and vitamin D.
• Osteoporosis is a complex, multifactorial disorder, and ensuring a high calcium intake is only one of several necessary preventive strategies.
• High calcium intakes are especially important as adjunctive therapy in patients with osteoporosis receiving currently approved bone-active drugs. With estrogen, for example, high calcium intakes greatly augment the protective estrogen effect.
Key teaching points:
• A very large body of evidence establishes that high calcium intakes augment bone gain during growth, retard age-related bone loss, and reduce osteoporotic fracture risk.
• Dairy sources of calcium are at least as efficacious in this respect as are calcium supplements.
• The protein and sodium contents of dairy foods do not adversely affect the bone benefit of the dairy package of calcium, phosphorus, protein, and vitamin D.
• Osteoporosis is a complex, multifactorial disorder, and ensuring a high calcium intake is only one of several necessary preventive strategies.
• High calcium intakes are especially important as adjunctive therapy in patients with osteoporosis receiving currently approved bone-active drugs. With estrogen, for example, high calcium intakes greatly augment the protective estrogen effect.
Notes
1 Another study, not directly assessing calcium intake, showed that fracture risk in adolescents was a function of bone mass, just as in the elderly [Citation149]. This latter finding established that strong bones confer a current, and not just a delayed, benefit, even in children.