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verify, fracture risk represents the best measure for bone health for this life stage. One important caution is that the estimation of the effect of fracture risk is greatly complicated by the limited evidence concerning dose–response data relative to calcium intake. Importantly, calcium balance studies to determine the levels of calcium that result in neutral calcium balance are lacking in the literature for persons over the age of 70 years. Hunt and Johnson (2007) were able to incorporate only two women over the age of 70 years.

The analysis of Tang et al. (2007) is limited by the nature of the studies available, in that most studies tested intervention levels at or above 1,200 mg/day and often did not report total calcium intake. Those studies in the Tang et al. (2007) analysis that examined calcium alone, without vitamin D supplementation, were few. The authors’ conclusion that 1,200 mg/day was beneficial relative to reduced fracture risk is relevant, but may be compromised by the inability to examine the effectiveness at other levels. In contrast to the Tang et al. (2007) analysis, Peacock et al. (2000), Grant et al. (2005), and Prince et al. (2006), who studied calcium intake alone, were unable to demonstrate benefits for bone health among persons over 70 years of age with supplemental calcium intakes (750 to 1,200 mg/day); however, a compliance sub-analysis conducted by Prince et al. (2006) suggested reduced fracture incidence with calcium supplementation of 1,200 mg/day.

The data available do not clearly elucidate a requirement for calcium and primarily suggest values that may result in covering nearly all of the population group in terms of reduced fracture risk. That is, the available studies were not examining the levels of calcium intake that were effective, but rather were examining whether their administered calcium intake was effective. Further, the benefit of calcium supplementation was evident in the case of sub-analysis on the basis of compliance, which, while informative, are not ideal data sets. In addition, the populations studied varied considerably, many could be considered at high risk (such as institutionalized older persons and persons with low body weight), and the effect of calcium supplementation was usually not taken into account in the context of vitamin D status or existing calcium nutriture.

For this reason, public health protection was considered, and it was determined that a requirement somewhat above that established by calcium balance studies for bone maintenance was appropriate despite the unknowns and the inability to clearly estimate a dose–response for calcium relative to fracture risk. As with those estimates used for postmenopausal women, a 200 mg/day calcium increment was added to the estimated requirements for younger persons, resulting in an EAR value of 1,000 mg of calcium per day. It is assumed that the rapid and notable bone loss ob-



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