Minihane A M, Fairweather-Tait S J
Institute of Food Research, Norwich Research Park, Colney, United Kingdom.
Am J Clin Nutr. 1998 Jul;68(1):96-102. doi: 10.1093/ajcn/68.1.96.
The short-term effect of calcium supplements (1200 mg Ca/d) on daily nonheme-iron absorption was measured in 14 healthy adult volunteers by using stable isotope extrinsic labeling and fecal monitoring techniques. Mean (+/- SEM) nonheme-iron absorption from a low-calcium (< 320 mg/d), moderately high-iron (15 mg/d) diet was 15.8 +/- 2.1%, but in the presence of calcium (400 mg/meal) as calcium carbonate, absorption fell significantly to 4.7 +/- 1.4% (P < 0.001). The long-term effect of consuming calcium supplements with meals (1200 mg Ca/d) on body iron (functional and storage iron) was investigated in 11 iron-replete adults over a 6-mo period. An unsupplemented control group (n = 13) was also monitored to correct for any seasonal changes in the biochemical measurements. There were no changes in any of the hematologic indexes, including hemoglobin, hematocrit, zinc protoporphyrin, and plasma ferritin resulting from the calcium supplementation. The results clearly show that long-term supplementation with calcium did not reduce plasma ferritin concentrations in iron-replete adults consuming a Western-style diet containing moderate to high amounts of calcium in most meals.
采用稳定同位素外源性标记和粪便监测技术，对14名健康成年志愿者测定了补钙剂（1200毫克钙/天）对每日非血红素铁吸收的短期影响。来自低钙（<320毫克/天）、中等高铁（15毫克/天）饮食的平均（±标准误）非血红素铁吸收率为15.8±2.1%，但在碳酸钙形式的钙（每餐400毫克）存在的情况下，吸收率显著降至4.7±1.4%（P<0.001）。在11名铁储备充足的成年人中，研究了餐时服用补钙剂（1200毫克钙/天）对机体铁（功能性铁和储存铁）的长期影响，为期6个月。还监测了一个未补充钙剂的对照组（n = 13），以校正生化指标的任何季节性变化。补钙后，包括血红蛋白、血细胞比容、锌原卟啉和血浆铁蛋白在内的任何血液学指标均无变化。结果清楚地表明，长期补充钙剂不会降低食用大多数餐食中钙含量适中至高的西式饮食的铁储备充足成年人的血浆铁蛋白浓度。
