Considerable uncertainty exists regarding optimal intakes of calcium. This is reflected in markedly different recommended daily intakes in various countries [1]. A recent paper reports a study which was carried out in the United States among 4958 community-dwelling women and 5003 men aged 20 years or more [2]. According to the results, a higher calcium intake was significantly associated with higher bone density (p value for trend = 0.005) only for women with serum 25-hydroxyvitamin D [25(OH)D] status below 50 nmol/l. Among men, there was no significant association between a higher calcium intake beyond the upper end of the lowest quartile (626 mg/day) and bone density within all 25(OH)D categories. Among both genders, bone density increased stepwise and significantly with higher 25(OH)D concentrations(< 50 nmol/l, 50–74 nmol/l, ≥ 75 nmol/l); for women, the p value for trend was < 0.0001, and for men, p = 0.0001.
Author(s)
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Mark P. Brincat
Department of Obstetrics and Gynaecology, Mater Dei Hospital, BKara Bypass, Malta -
Jean Calleja-Agius
Department of Obstetrics and Gynaecology, Mater Dei Hospital, BKara Bypass, Malta
Citations
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http://www.ncbi.nlm.nih.gov/pubmed/19113911 -
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http://www.ncbi.nlm.nih.gov/pubmed/18065599
