Johnson M A, Smith M M, Edmonds J T
Department of Foods and Nutrition, The University of Georgia, Athens 30602, USA.
Am J Clin Nutr. 1998 May;67(5 Suppl):1035S-1040S. doi: 10.1093/ajcn/67.5.1035S.
High intakes of iron, zinc, or manganese can interfere with copper absorption. Thus, the purpose of this study was to determine whether the amounts and chemical forms of iron, zinc, manganese, and copper added to food products and nutritional supplements might pose a threat to copper status. More than 25% of the vitamin and mineral supplements examined contained no copper, 40% contained the poorly absorbed cupric oxide, and < 30% contained a highly bioavailable form of copper such as cupric sulfate or cupric chloride. Nearly 40% of the prenatal supplements examined contained both iron and zinc without a nutritionally significant amount of copper. More than 80% of the infant formulas examined had ratios of iron to copper exceeding 20:1, which is higher than the recommended ratios of 10-17:1. None of the 40 ready-to-eat breakfast cereals examined were fortified with copper or manganese although 50% of these cereals contained > or = 25% of the reference daily intake for both iron and zinc. Copper availability could be improved by reformulation of several food products and supplements.
高摄入量的铁、锌或锰会干扰铜的吸收。因此，本研究的目的是确定添加到食品和营养补充剂中的铁、锌、锰和铜的含量及化学形式是否可能对铜的状态构成威胁。超过25%的所检测维生素和矿物质补充剂不含铜，40%含有吸收性差的氧化铜，不到30%含有生物利用率高的铜形式，如硫酸铜或氯化铜。近40%的所检测产前补充剂含有铁和锌，但铜含量未达到营养显著水平。超过80%的所检测婴儿配方奶粉铁与铜的比例超过20:1，高于推荐比例10 - 17:1。所检测的40种即食早餐谷物中没有一种添加了铜或锰，尽管其中50%的谷物铁和锌含量均达到或超过每日参考摄入量的25%。通过重新配方一些食品和补充剂，可以提高铜的利用率。
