Abrams S A, Grusak M A, Stuff J, O'Brien K O
US Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Houston, TX 77030-2600, USA.
Am J Clin Nutr. 1997 Nov;66(5):1172-7. doi: 10.1093/ajcn/66.5.1172.
Few data are available regarding calcium and magnesium absorption and endogenous fecal excretion in children. We used a multitracer stable isotope technique to assess calcium and magnesium balance in 12 boys and 13 girls aged 9-14 y (mean weight: 42 kg) maintained on relatively high calcium intakes (mean: 1310 +/- 82 mg/d). There were no significant differences in absorption of calcium or magnesium from milk between boys and girls. Calcium retention (balance) correlated positively with calcidiol (25-hydroxyvitamin D) concentration (r = 0.48, P = 0.02) and serum alkaline phosphatase activity (r = 0.44, P = 0.03). There was no significant relation between magnesium balance and concentration. When data from this study were combined with our previously reported data, an increase in total calcium absorption was seen for pubertal (Tanner stages 2-4) but not prepubertal (Tanner stage 1) white children over the range of intakes from approximately 750 to 1350 mg/d. Despite intakes similar to the 1989 recommended dietary allowance for magnesium (mean intake: 6.4 +/- 1.2 mg.kg-1.d-1), 11 of the 25 subjects (6 girls and 5 boys) were in negative magnesium balance. We conclude that benefits from higher calcium intakes, < or = 1350 mg/d, were most apparent in pubertal children. In addiction, higher magnesium intakes should be considered for children.
关于儿童钙和镁的吸收以及内源性粪便排泄的数据很少。我们采用多示踪稳定同位素技术，对12名9至14岁（平均体重：42千克）的男孩和13名女孩进行了评估，这些儿童维持相对较高的钙摄入量（平均：1310±82毫克/天）。男孩和女孩从牛奶中吸收钙或镁没有显著差异。钙潴留（平衡）与骨化二醇（25-羟基维生素D）浓度呈正相关（r = 0.48，P = 0.02），与血清碱性磷酸酶活性呈正相关（r = 0.44，P = 0.03）。镁平衡与浓度之间没有显著关系。当将本研究的数据与我们之前报告的数据相结合时，发现青春期（坦纳分期2至4期）而非青春期前（坦纳分期1期）的白人儿童在摄入量从约750至1350毫克/天的范围内，总钙吸收有所增加。尽管摄入量与1989年镁的推荐膳食摄入量相似（平均摄入量：6.4±1.2毫克·千克⁻¹·天⁻¹），但25名受试者中有11名（6名女孩和5名男孩）处于负镁平衡状态。我们得出结论，钙摄入量增加至≤1350毫克/天的益处，在青春期儿童中最为明显。此外，应考虑让儿童摄入更多的镁。
