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ally > 65 years) and typically include vitamin D administration. Likewise, organizations such as the National Osteoporosis Foundation have issued guidelines that do not stipulate BMD testing for men until the age of 70 years (NOF, 2008), whereas they recommend BMD testing at an earlier age for women. Given this context, the data from Hunt and Johnson (2007) with respect to neutral calcium balance among adults can provide some information for specifying requirements among men between the ages of 51 and 70 years. Although there were only two men over the age of 50 years in the Hunt and Johnson (2007) study, the absence of evidence that significant changes occur in skeletal maintenance for men in their 50s and 60s results in the assumption that their needs are akin to those of younger men. Therefore, the calcium EAR and RDA for men 51 to 70 years of age are set at the same levels as for persons 31 to 50 years of age: the EAR for calcium is established as 800 mg/day, and the RDA for calcium is 1,000 mg/day. The newer calcium balance data are used with caution, given its limitations for this purpose.

Women 51 through 70 years of age are considered separately from men. Although it is evident that calcium intake does not prevent bone less during the first few years of menopause, there is the question of whether or to what extent calcium intake can mitigate the loss of bone during and immediately following the onset of menopause. Although about half of the women in the Hunt and Johnson (2007) study were over the age of 50, the authors did not stratify on the basis of menopausal status. Therefore, there are some uncertainties surrounding the use of these newer calcium balance data for the purposes of determining an EAR and RDA for women. However, other information is available that can be useful. Absolute hip fracture rates are lower than for women in this age rang than for women over the age 70 but still greater than for premenopausal women. Moreover, BMD is a reliable predictor for fracture risk later in life and therefore becomes a useful measure for DRI purposes.

The available data for BMD among women 51 through 70 years of age provide mixed results concerning the relationship between BMD and calcium intake in menopausal women. This may be due in part to study protocols—which usually have relied on a single dose of 1,000 mg or more daily—that have failed to clarify background diet or estimate total intake. On balance, there is somewhat more evidence for a benefit of higher calcium intake among women over the age of 60 years, a group that is likely about half of the DRI life stage of women 51 through 70 years of age. Specifically, the meta-analysis conducted by Tang et al. (2007), which included studies in women ranging in mean age from 50 to 85 years, indicated that total calcium intake alone equal to 1,200 mg or more per day had a positive effect on BMD as well as a modest (relative risk [RR] = 0.88; 95%



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