铁是人体必需的微量元素之一,因为它是血红蛋白和肌蛋白的组成成分,参与氧和二氧化碳的运输。铁还是细胞色素和过氧化氢酶、过氧化物酶的组成成分,在呼吸和生物氧化过程中起重要作用。因此,过去曾强调,发育儿童、妇女尤其是孕妇、老年人和营养不佳的人应在饮食中多补充铁。 然而,今年初美国和芬兰分别发表的两项研究结果证实发达国家和生活水平较高的人群体内的铁含量已经过高,而过高的铁可增加患癌的危险。这个结论引起了世界各国不少人的恐慌。而且美国的研究还认为是食品中添加的铁造成了危险。 上述结论一发表也受到一些科学家的反驳。他们承认体内高水平的铁可能引起癌症,但是只有那些从食物中能吸收大量铁的人才会受到影响,并不是每个人都吃富含铁的食品。还有一些人认为高水平的铁也许是癌症的结果而不是癌症的原因。 美国的研究是由美国华盛顿北大西洋实验室的流行病学教授理查德·史蒂文斯主持的,他带领一个研究组查阅了8500名男人和妇女的保健资料。主要调查人们体内的转铁蛋白。这种蛋白充满铁离子,通过转 Iron is one of the essential trace elements of the human body because it is a component of hemoglobin and muscle protein involved in the transport of oxygen and carbon dioxide. Iron is also a cytochrome and catalase, a component of peroxidase, which plays an important role in respiratory and bio-oxidation processes. Therefore, it has been emphasized in the past that children in developing countries, especially pregnant women, the elderly and those with poor nutrition, should supplement their diet with iron. However, two studies, published separately by the United States and Finland earlier this year, confirm that iron levels are already high in developed countries and populations with higher standards of living, while excessively high levels of iron increase the risk of cancer. This conclusion has aroused the panic of many people in all countries in the world. And the U.S. study also found it dangerous to add iron to food. The publication of the above conclusion was also rebutted by some scientists. They admit that high levels of iron in the body can cause cancer, but only those who can absorb large quantities of iron from their food are affected, not everybody is eating iron-rich foods. Still others believe that high levels of iron may be the result of cancer rather than cancer. The American study, moderated by Richard Stevens, a professor of epidemiology at the North Atlantic Laboratory in Washington, USA, led a team that looked at the health information of 8,500 men and women. The main survey of people’s body transferrin. This protein is full of iron ions, by turning