铁的危害

Iron's Dangers 铁的危害

Q: You believe iron is a deadly substance. Why?

Iron is a potentially toxic heavy metal. In excess, it can cause cancer, heart disease, and other illnesses. 问:你认为铁是一种致命的物质。为什么?

铁是一种潜在的有毒重金属。过量会导致癌症、心脏病和其他疾病。

Q: Could you tell us about some of these studies?

In the 1960s the World Health Organization found that when iron supplements were given to anemic people in Africa, there was a great increase in the death rate from infectious diseases, especially malaria. Around the same time, research began to show that the regulation of iron is a central function of the immune system, and that this seems to have evolved because iron is a basic requirement for the survival and growth of cells of all types, including bacteria, parasites, and cancer. The pioneer researcher in the role of iron in immunity believed that an excess of dietary iron contributed to the development of leukemia and lymphatic cancers. Just like lead, mercury, cadmium, nickel and other heavy metals, stored iron produces destructive free radicals. The harmful effects of iron-produced free radicals are practically indistinguishable from those caused by exposure to X-rays and gamma rays; both accelerate the accumulation of age-pigment and other signs of aging. Excess iron is a crucial element in the transformation of stress into tissue damage by free radicals. 问:你能给我们讲讲这些研究吗?

20世纪60年代,世界卫生组织发现,当非洲贫血患者服用铁补充剂时,传染病,尤其是疟疾,死亡率大幅上升。大约在同一时期,研究开始表明,对铁的调节是免疫系统的一个中心功能,而这似乎已经进化了,因为铁是所有类型的细胞(包括细菌、寄生虫和癌症)生存和生长的基本需求。研究铁在免疫中的作用的先驱研究者认为,饮食中过量的铁会导致白血病和淋巴癌的发生。就像铅、汞、镉、镍和其他重金属一样,储存的铁也会产生破坏性的自由基。由铁产生的自由基的有害影响实际上与暴露于x射线和伽玛射线所造成的有害影响难以区分;两者都会加速衰老色素和其他衰老迹象的积累。过量的铁是自由基将压力转化为组织损伤的关键因素。

For about 50 years, it has been known that blood transfusions damage immunity, and excess iron has been suspected to be one of the causes for this. People who regularly donate blood, on the other hand, have often been found to be healthier than non-donors, and healthier than they were before they began donating. 50多年来,人们一直认为输血会损害免疫力,而过量的铁被认为是造成这种情况的原因之一。另一方面,经常献血的人往往被发现比不献血的人更健康,而且比他们开始献血前更健康。

In one of Hans Selye's pioneering studies, he found that he could experimentally produce a form of scleroderma (hardening of the skin) in animals by administering large doses of iron, followed by a minor stress. He could prevent the development of the condition by giving the animals large doses of vitamin E, suggesting that the condition was produced by iron's oxidative actions. 在汉斯·塞利(Hans Selye)的一项开创性研究中,他发现他可以通过给动物注射大剂量的铁,然后施加较小的压力,通过实验产生一种硬皮病(皮肤硬化)。他可以通过给动物服用大剂量的维生素E来防止这种疾病的发展,这表明这种疾病是由铁的氧化作用产生的。

Excess iron's role in infectious diseases is now well established, and many recent studies show that it is involved in degenerative brain diseases, such as Parkinson's, ALS (Lou Gehrig's disease), Huntington's chorea, and Alzheimer's disease. Iron is now believed to have a role in skin aging, atherosclerosis, and cataracts of the lenses of the eyes, largely through its formation of the "age pigment." 目前,铁在传染性疾病中的作用已经得到证实,许多最近的研究表明,铁与退行性脑疾病有关,如帕金森病、肌萎缩性脊髓侧索硬化症(ALS)、亨廷顿舞蹈病和阿尔茨海默病。现在人们认为,铁在皮肤老化、动脉粥样硬化和眼睛晶状体白内障中发挥作用,主要是通过它形成的“年龄色素”。(老年斑)

Q: How does excess iron accelerate our aging process?

During aging, our tissues tend to store an excess of iron. There is a remarkably close association between the amount of iron stored in our tissues and the risk of death from cancer, heart disease, or from all causes. This relationship between iron and death rate exists even during childhood, but the curve is downward until the age of 12, and then it rises steadily until death. The shape of this curve, representing the iron burden, is amazingly similar to the curves representing the rate of death in general, and the rate of death from cancer. There is no other relationship in biology that I know of that has this peculiar shape, with its minimum at the age of 12, and its maximum in old age at the time of death. 问:过量的铁是如何加速我们的衰老过程的?

在衰老过程中,我们的组织往往会储存过量的铁。我们组织中储存的铁的数量与癌症、心脏病或其他各种原因的死亡风险之间有着非常密切的联系。铁元素和死亡率之间的关系甚至在儿童时期就存在,但曲线在12岁之前呈下降趋势,然后稳步上升,直到死亡。这条曲线的形状,代表铁的负担,与代表一般死亡率和癌症死亡率的曲线惊人地相似。在我所知的生物学中,没有任何一种关系具有这种特殊的形状,最小的是在12岁,最大的是在老年死亡的时候。

One of the major lines of aging research, going back to the early part of this century, was based on the accumulation of a brown material in the tissues known as "age-pigment." The technical name for this material, "lipofuscin," means "fatty brown stuff." In the 1960s, the "free radical theory" of aging was introduced by Denham Harman, and this theory has converged with the age-pigment theory, since we now know that the age-pigment is an oxidized mass of unsaturated fat and iron, formed by uncontrolled free radicals. Until a few years ago, these ideas were accepted by only a few researchers, but now practically every doctor in the country accepts that free radicals are important in the aging process. A nutrition researcher in San Diego suspected that the life-extending effects of calorie restriction might be the result of a decreased intake of toxins. He removed the toxic heavy metals from foods, and found that the animals which ate a normal amount of food lived as long as the semi-starved animals. Recently, the iron content of food has been identified as the major life-shortening factor, rather than the calories. [Choi and Yu, Age vol. 17, page 93, 1994.] 衰老研究的主要方向之一,可以追溯到本世纪初,是基于组织中称为“衰老色素”的棕色物质的积累。这种物质的学名是“脂褐素”,意思是“脂肪棕色物质”。20世纪60年代,德纳姆·哈曼(Denham Harman)提出了衰老的“自由基理论”,这一理论与年龄色素理论相融合,因为我们现在知道,年龄色素是不受控制的自由基形成的不饱和脂肪和铁的氧化物质。直到几年前,这些观点还只有少数研究人员接受,但现在几乎所有美国医生都承认自由基在衰老过程中很重要。圣地亚哥的一名营养研究人员怀疑,限制热量摄入延长寿命的效果可能是毒素摄入量减少的结果。他从食物中去除有毒的重金属,发现吃正常量食物的动物活得和半饥饿的动物一样长。最近,食物中的铁含量已经被认为是缩短寿命的主要因素,而不是卡路里。时代》第17卷,第93页,1994。

Q: Exactly how much iron do we need to eat?

Children's nutritional requirements are high, because they are growing, but there are indications that in the U.S. even children eat too much iron.

Some researchers are concerned that the iron added to cereals is contributing to the incidence of leukemia and cancers of the lymphatic tissues in children. [Goodfield, 1984.] During the time of rapid growth, children are less likely than adults to store too much iron. At birth, they have a large amount of stored iron, and this decreases as they "grow into it." It is after puberty, when growth slows and the sex hormones are high, that the storage of iron increases. [Blood, Sept., 1976.] In a study of the "malnourished" children of migrant fruit pickers in California, these children who were "seriously anemic" were actually more resistant to infectious diseases than were the "well nourished" middle class children in the same region. 问:我们到底需要吃多少铁?

儿童的营养需求很高,因为他们在成长,但有迹象表明,在美国,即使是儿童也摄入了太多的铁。

一些研究人员担心,添加到谷物中的铁会导致儿童白血病和淋巴组织癌症的发病率。[Goodfield, 1984。在快速生长时期,儿童比成人储存过多铁的可能性小。在出生时,它们储存了大量的铁,随着它们“长大”,储存的铁会减少。青春期过后,当生长放缓,性激素分泌旺盛时,铁的储存就会增加。血,1976年9月。。一项针对加州水果采摘移民的“营养不良”儿童的研究表明,这些“严重贫血”的儿童实际上比同一地区“营养良好”的中产阶级儿童对传染病的抵抗力更强。

If the normal amount of dietary iron causes an increased susceptibility to infections even in children, and if a subnormal amount of iron slows the aging process, I think we are going to have to reconsider our ideas of nutritional adequacy, to look at the long range effects of diet, as well as the immediate effects. My current studies have to do with analyzing our ability to handle stress safely, in relation to our diet. I believe our nutritional recommendations for iron have to be revised sharply downward. 如果正常的膳食铁导致孩子,甚至对感染的易感性增加,如果数量低于正常的的铁减缓衰老的过程,我认为我们将不得不重新考虑我们的想法的营养充足,饮食的长期影响,以及直接影响。我目前的研究是分析我们安全处理压力的能力,与我们的饮食有关。我认为我们对铁的营养建议必须大幅下调。

Q. Don't women need extra iron?

That's a misunderstanding.

Doctors generally don't realize that only a few milligrams of iron are lost each day in menstruation. The real issue is that you can hardly avoid getting iron, even when you try.

Women absorb iron much more efficiently than men do. From a similar meal, women will normally absorb three times as much iron as men do. When pregnant, their higher estrogen levels cause them to absorb about nine times as much as men. Every time a woman menstruates, she loses a little iron, so that by the age of 50 she is likely to have less iron stored in her tissues than a man does at the same age, but by the age of 65 women generally have as much excess iron in their tissues as men do. (During those 15 years, women seem to store iron at a faster rate than men do, probably because they have more estrogen.) At this age their risk of dying from a heart attack is the same as that of men. Some women who menstruate can donate blood regularly without showing any tendency to become anemic. 问:女性不需要额外的铁吗?

这是一个误解。

医生们通常没有意识到,在月经期间,每天只有几毫克的铁流失。真正的问题是,你很难避免得到铁,即使你尝试。

女性吸收铁的效率比男性高得多。同样的一餐,女性通常会比男性多吸收三倍的铁。当她们怀孕时,较高的雌激素水平使她们吸收的雌激素大约是男性的九倍。每次女人月经来潮,她失去一个小铁,所以,到50岁的她可能会减少铁储存在组织比一个人在同一时代,但65岁的女性通常有多余的铁在他们的组织和男性一样。(在这15年里,女性储存铁的速度似乎比男性快,这可能是因为她们体内的雌激素更多。)在这个年龄,他们死于心脏病发作的风险与男性相同。一些经期妇女可以定期献血,而不会表现出任何贫血的倾向。

Since the custom of giving large iron supplements to pregnant women has been established, there has been an increase in jaundice of the newborn. It has been observed that women who didn't take iron supplements during pregnancy have healthy babies that don't develop jaundice. I have suggested that this could be because they haven't been poisoned by iron. Those supplements could also be a factor in the increased incidence of childhood cancer. 由于给孕妇大量补充铁的习俗已经确立,新生儿黄疸病的发病率有所增加。据观察,怀孕期间没有补充铁元素的女性生出的婴儿健康,不会患上黄疸。我认为这可能是因为他们没有被铁毒害。这些补充剂也可能是儿童癌症发病率增加的一个因素。

Q: Don't you need iron supplements if you are anemic?

In general, no.

Many doctors think of anemia as necessarily indicating an iron deficiency, but that isn't correct. 100 years ago, it was customary to prescribe arsenic for anemia, and it worked to stimulate the formation of more red blood cells. The fact that arsenic, or iron, or other toxic material stimulates the formation of red blood cells doesn't indicate a "deficiency" of the toxin, but simply indicates that the body responds to a variety of harmful factors by speeding its production of blood cells. Even radiation can have this kind of stimulating effect, because growth is a natural reaction to injury. Between 1920 and 1950, it was common to think of "nutritional growth factors" as being the same as vitamins, but since then it has become common to use known toxins to stimulate the growth of farm animals, and as a result, it has been more difficult to define the essential nutrients. The optimal nutritional intake is now more often considered in terms of resistance to disease, longevity or rate of aging, and even mental ability. 问:如果你贫血,你不需要补铁吗?

一般来说,没有。

许多医生认为贫血是铁缺乏的必然表现,但这是不正确的。100年前,人们习惯用砷来治疗贫血,砷可以刺激红细胞的形成。砷、铁或其他有毒物质刺激红细胞形成的事实,并不表明毒素“缺乏”,而只是表明身体对各种有害因素的反应,加速了血细胞的生成。甚至辐射也能有这种刺激作用,因为生长是受伤后的自然反应。在1920年至1950年之间,这是普遍认为的“营养生长因子”是一样的维生素,但自那以来已成为普遍使用已知毒素刺激农场动物的生长,因此,它更难以定义必需营养素。现在,最理想的营养摄入更多地是考虑到抵抗疾病、长寿或衰老速度,甚至智力。

An excess of iron, by destroying vitamin E and oxidizing the unsaturated fats in red blood cells, can contribute to hemolytic anemia, in which red cells are so fragile that they break down too fast. In aging, red cells break down faster, and are usually produced more slowly, increasing the tendency to become anemic, but additional iron tends to be more dangerous for older people. 过量的铁会破坏维生素E,氧化红细胞中的不饱和脂肪,从而导致溶血性贫血。在溶血性贫血中,红细胞非常脆弱,分解过快。在衰老过程中,红细胞分解得更快,而且通常生成得更慢,增加了贫血的倾向,但额外的铁元素往往对老年人更危险。

Anemia in women is caused most often by a thyroid deficiency (as discussed in the chapter on thyroid), or by various nutritional deficiencies. Estrogen (even in animals that don't menstruate) causes dilution of the blood, so that it is normal for females to have lower hemoglobin than males. 妇女贫血最常由甲状腺缺乏引起(如甲状腺章节所述),或由各种营养缺乏引起。雌性激素(即使在没有月经的动物体内也是如此)会稀释血液,所以雌性的血红蛋白低于雄性是正常的。

Q. What should I do if my doctor tells me I'm anemic? Is there any situation in which a person needs to take iron supplements?

Iron deficiency anemia does exist, in laboratory situations and in some cases of chronic bleeding, but I believe it should be the last-suspected cause of anemia, instead of the first. It should be considered as a possible cause of anemia only when very specific blood tests show an abnormally low degree of iron saturation of certain proteins. Usually, physicians consider the amount of hemoglobin or of red cells in the blood as the primary indicator of a need for iron, but that just isn't biologically reasonable.

If a large amount of blood is lost in surgery, a temporary anemia might be produced, but even then it would be best to know whether the iron stores are really depleted before deciding whether an iron supplement would be reasonable. Liver (or even a water extract of wheat germ) can supply as much iron as would be given as a pill, and is safer. 问:如果我的医生告诉我贫血,我该怎么办?在什么情况下需要补充铁元素?

缺铁性贫血确实存在,在实验室的情况下,在一些慢性出血的情况下,但我认为它应该是最后一个被怀疑的贫血原因,而不是第一个。只有当特定的血液检查显示某些蛋白质的铁饱和度异常低时,才应考虑贫血的可能原因。通常,医生认为血液中血红蛋白或红细胞的数量是铁需求的主要指标,但这在生物学上是不合理的。

如果在手术中大量失血,可能会产生暂时性贫血,但即便如此,在决定补铁是否合理之前,最好先了解铁的储备是否真的耗尽了。肝脏(甚至小麦胚芽的水提取物)可以提供与药片一样多的铁,而且更安全。

Q. What foods contain iron?

Flour, pasta, etc., almost always contain iron which has been artificially added as ferrous sulfate, because of a federal law. Meats, grains, eggs, and vegetables naturally contain large amounts of iron. A few years ago, someone demonstrated that they could pick up a certain breakfast cereal with a magnet, because of the added iron. Black olives contain iron, which is used as a coloring material. You should look for "ferrous" or "ferric" or "iron" on the label, and avoid foods with any added iron. Many labels list "reduced iron," meaning that iron is added in the ferrous form, which is very reactive and easily absorbed. 问:哪些食物含铁?

根据联邦法律,面粉、意大利面等几乎总是含有铁,而铁是被人为地作为硫酸亚铁添加的。肉类、谷物、鸡蛋和蔬菜天然就含有大量的铁。几年前,有人证明他们可以用磁铁吸走某种早餐麦片,因为添加了铁。黑橄榄含有铁,铁是一种着色材料。你应该在标签上寻找“含铁”或“含铁”或“铁”,避免含有任何添加铁的食物。许多标签都列出了“还原铁”,这意味着铁是以亚铁的形式添加的,这种形式非常活泼,很容易吸收。

Q.: Why does federal law require the addition of iron to those foods?

Industrially processed grains have most of the nutrients, such as vitamin E, the B vitamins, manganese, magnesium, etc., removed to improve the products' shelf life and efficiency of processing, and the government required that certain nutrients be added to them as a measure to protect the public's health, but the supplementation did not reflect the best science even when it was first made law, since food industry lobbyists managed to impose compromises that led to the use of the cheapest chemicals, rather than those that offered the greatest health benefits. For example, studies of processed animal food had demonstrated that the addition of iron (as the highly reactive form, ferrous sulfate, which happens to be cheap and easy to handle) created disease in animals, by destroying vitamins in the food. You should read the label of ingredients and avoid products that contain added iron, when possible. 问:为什么联邦法律要求在这些食物中添加铁元素?

工业加工的谷物含有大部分的营养素,如维生素E,维生素B,锰,镁等,为了提高产品的保质期和加工效率,政府要求添加某些营养素以保护公众的健康,但是,即使在最初制定法律的时候,这种补充剂也没有反映出最好的科学,因为食品行业的说客设法强加妥协,导致使用最便宜的化学物质,而不是那些对健康有最大好处的化学物质。例如,对动物加工食品的研究表明,添加铁(作为高反应形式的硫酸亚铁,碰巧便宜且容易处理)会破坏食品中的维生素,从而在动物中造成疾病。你应该阅读成分标签,尽可能避免含有添加铁的产品。

Q: Can cooking in an iron frying pan put iron into food?

Yes, especially if the food is acidic, as many sauces are. The added iron will destroy vitamins in the food, besides being potentially toxic in itself. 问:用铁锅烹饪能让食物变得含铁吗?

是的,尤其当食物是酸性的时候,铁就像很多酱汁一样。添加铁不仅会破坏食物中维生素,而且铁本身也有潜在的毒性。

Q: What about aluminum?

Aluminum and iron react similarly in cells and are suspected causes of Alzheimer's disease. The aluminum industry started propagandizing more than 50 years ago about the "safety" of aluminum utensils, claiming that practically none of the toxic metal gets into the food. Recent research showed that coffee percolated in an aluminum pot contained a large amount of dissolved aluminum, because of coffee's acidity. 问:那铝呢? 铝和铁在细胞中的反应相似,被怀疑是阿尔茨海默病的病因。

铝行业在50多年前就开始宣传铝器皿的“安全性”,声称几乎没有有毒金属进入食物。最近的研究表明,由于咖啡的酸性,在铝壶中渗透的咖啡含有大量的溶解铝。

Q: What kind of cooking pots or utensils are safe?

Glass utensils are safe, and certain kinds of stainless steel are safe, because their iron is relatively insoluble. Teflon-coated pans are safe unless they are chipped. 问:什么样的烹饪锅或器皿是安全的?

玻璃器皿是安全的,某些种类的不锈钢是安全的,因为它们的铁是相对不溶解的。特氟隆涂层锅是安全的,除非有破损。

Q: How do I know which stainless steels are safe?

There are two main types of stainless steel, magnetic and nonmagnetic. The nonmagnetic form has a very high nickel content, and nickel is allergenic and carcinogenic. It is much more toxic than iron or aluminum. You can use a little "refrigerator magnet" to test your pans. The magnet will stick firmly to the safer type of pan. 问:我如何知道哪些不锈钢是安全的?

不锈钢主要有两种类型,磁性和非磁性。非磁性的镍含量非常高,镍会引起过敏和致癌。它的毒性比铁和铝大得多。你可以用一个小的“冰箱磁铁”来测试你的平底锅。磁铁会牢牢地粘在较安全的平底锅上。

Q: Why is there iron in most multi-vitamin and mineral products?

Although several researchers have demonstrated that iron destroys vitamins, there is enough wishful thinking in industry, government, and the consuming public, that such mistakes can go on for generations before anyone can mobilize the resources to bring the truth to the public. 10 years ago, I thought it was a hopeful sign of increased awareness of iron's danger when the manufacturer of a new iron product mentioned in the Physician's Desk Reference that it hadn't yet been reported to cause cancer. 问:为什么大多数复合维生素和矿物质产品中都含有铁元素?

尽管一些研究人员已经证明铁会破坏维生素,但在工业界、政府和消费者中,有足够的一厢情愿的想法,认为这样的错误可能会持续几代人,直到有人能够调动资源,将真相告诉公众。十年前,当一种新的含铁产品的制造商在《医生办公桌参考》中提到它尚未被报道会导致癌症时,我认为这是一个希望的信号,表明人们越来越意识到铁的危害。

Q. I can't avoid all those foods, especially the bread and grains. What can I do to keep the iron I ingest from harming me?

Iron destroys vitamin E, so vitamin E should be taken as a supplement. It shouldn't be taken at the same time as the iron-contaminated food, because iron reacts with it in the stomach. About 100 mg. per day is adequate, though our requirement increases with age, as our tissue iron stores increase. Coffee, when taken with food, strongly inhibits the absorption of iron, so I always try to drink coffee with meat. Decreasing your consumption of unsaturated fats makes the iron less harmful. Vitamin C stimulates the absorption of iron, so it might be a good idea to avoid drinking orange juice at the same meal with iron-rich foods. A deficiency of copper causes our tissues to retain an excess of iron, so foods such as shrimp and oysters which contain abundant copper should be used regularly. 问:我无法避免所有这些食物,尤其是面包和谷物。我该怎么做才能不让我摄入的铁伤害我呢?

铁会破坏维生素E,所以维生素E应该作为补充剂服用。它不应该与受铁污染的食物同时服用,因为铁在胃里会与食物发生反应。大约100毫克。每天就足够了,尽管随着年龄的增长,人体组织铁储备的增加,我们的需求量也会增加。咖啡和食物一起喝,会强烈抑制铁的吸收,所以我总是试着和肉一起喝咖啡。减少不饱和脂肪的摄入可以降低铁的危害。维生素C促进铁的吸收,所以在吃富含铁的食物时不要喝橙汁是个好主意。缺铜会导致我们的组织保留过量的铁,所以应该经常食用富含铜的食物,如虾和牡蛎。

Q: How does copper help us?

Copper is the crucial element for producing the color in hair and skin, for maintaining the elasticity of skin and blood vessels, for protecting against certain types of free radical, and especially for allowing us to use oxygen properly for the production of biological energy. It is also necessary for the normal functioning of certain nerve cells (substantia nigra) whose degeneration is involved in Parkinson's disease. The shape and texture of hair, as well as its color, can change in a copper deficiency. Too much iron can block our absorption of copper, and too little copper makes us store too much iron. With aging, our tissues lose copper as they store excess iron. Because of those changes, we need more vitamin E as we age. 问:铜对我们有什么帮助?

铜是产生头发和皮肤颜色的关键元素,是保持皮肤和血管弹性的关键元素,是保护我们免受某些类型的自由基的伤害的关键元素,尤其是让我们能够恰当地利用氧气来生产生物能量。它对某些神经细胞(黑质)的正常功能也是必要的,这些细胞的退化与帕金森氏病有关。在缺铜的情况下,头发的形状、质地以及颜色都会发生变化。过多的铁会阻碍我们对铜的吸收,而过少的铜会使我们储存过多的铁。随着年龄的增长,我们的组织在储存多余的铁的同时失去了铜。由于这些变化,随着年龄的增长,我们需要更多的维生素E。

SUMMARY: 总结

Iron is a potentially toxic heavy metal; an excess can cause cancer, heart disease, and other illnesses. 铁是一种潜在的有毒重金属;过量会导致癌症、心脏病和其他疾病。

Other heavy metals, including lead and aluminum, are toxic; pans and dishes should be chosen carefully. 其他重金属,包括铅和铝,都是有毒的;选择锅和盘子时要仔细。

Iron causes cell aging. 铁会导致细胞衰老。

Drinking coffee with iron rich foods can reduce iron's toxic effects. 吃含铁食物时喝咖啡可减少铁的毒性。

Use shrimp and oysters, etc., to prevent the copper deficiency which leads to excess storage of iron. 吃虾和牡蛎以防止缺铜导致的过量铁储存。

Avoid food supplements which contain iron. 避免含铁的补剂。

Take about 100 units of vitamin E daily; your vitamin E requirement increases with your iron consumption. 每天服用约100单位的维生素E;你对维生素E的需求会随着铁的摄入而增加。

GLOSSARY: 术语表

Free radicals are fragments of molecules that are very destructive to all cells and system of the body. 自由基是分子的碎片,对身体的所有细胞和系统都是毁灭性的。

Respiration refers to the absorption of oxygen by cells, which releases energy. The structure inside the cell in which energy is produced by respiration is called the mitochondrion. Oxidation refers to the combination of a substance with oxygen. This can be beneficial, as in normal respiration that produces energy, or harmful, as in rancidity, irradiation, or stress reactions. Antioxidants: Vitamin E and vitamin C are known as antioxidants, because they stop the harmful free-radical chain reactions which often involve oxygen, but they do not inhibit normal oxidation processes in cells. "Chain breaker" would be a more suitable term. It is often the deficiency of oxygen which unleashes the dangerous free-radical processes. Many substances can function as antioxidants/chain breakers: thyroxine, uric acid, biliverdin, selenium, iodine, vitamin A, sodium, magnesium, and lithium, and a variety of enzymes. Saturated fats work with antioxidants to block the spread of free-radical chain reactions. Age pigment is the brown material that forms spots on aging skin, and that accumulates in the lens of the eye forming cataracts, and in blood vessels causing hardening of the arteries, and in the heart and brain and other organs, causing their functions to deteriorate with age. It is made up of oxidized unsaturated oils with iron. 呼吸作用是指细胞吸收氧气,释放能量。细胞内由呼吸产生能量的结构叫做线粒体。氧化是指物质与氧结合。这可能是有益的,如在产生能量的正常呼吸中,也可能是有害的,如在酸败、辐照或应激反应中。抗氧化剂:维生素E和维生素C被称为抗氧化剂,因为它们能阻止有害的自由基链反应,而自由基链反应通常与氧气有关,但它们不能抑制细胞内正常的氧化过程。"断链者"是更合适的称呼。通常是缺氧释放了危险的自由基过程。许多物质可以作为抗氧化剂/断链剂:甲状腺素、尿酸、胆绿素、硒、碘、维生素A、钠、镁、锂和各种酶。饱和脂肪和抗氧化剂一起作用,阻止自由基连锁反应的扩散。老年性色素是一种棕色物质,它会在老化的皮肤上形成斑点,在眼睛的晶状体中积聚,形成白内障,在血管中积聚,导致动脉硬化,在心脏、大脑和其他器官中积聚,导致它们的功能随着年龄的增长而退化。它由含铁的氧化不饱和油组成。

Anemic means lacking blood, in the sense of not having enough red blood cells or hemoglobin. It is possible to have too much iron in the blood while being anemic. Anemia in itself doesn't imply that there is nutritional need for iron. 贫血是指血液缺乏,从没有足够的红细胞或血红蛋白的意义上说。贫血时,血液中有可能含有过多的铁。贫血本身并不意味着对铁有营养需求。

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Transfusions: Amer. J. of Surgery 155, p. 43, 1988. *A Finnish study, two years ago, indicated that high iron stores may increase heart attack risk: In People magazine, 1994: "Is iron a killer?" Dr. Jerome L. Sullivan, director of clinical labs of Veterans Affairs Medical Center at Charleston, S.C., in 1983 proposed that excess iron contributes to heart attacks.

University of Kuopio in Finland: Large-scale study (nearly 2,000 men, for up to five years; next to smoking, excess stored iron is the most significant identifiable risk factor for heart attacks. It is a stronger risk factor for heart attack than high blood pressure and cholesterol.

*Dec. 7, page 6E, Register Guard (Eugene, OR): US studies showed a weak connection between iron and heart disease, and a weak connection with the iron in red meat. Epidemiologists at the Pacific Northwest Laboratory in Washington have reported that the greater the concentration of iron in a person's blood, the greater his or her risk of cancer. Richard Stevens and his co-workers found the connection from examining cancer rates in more than 8,000 people who participated in the l971 National Health and Nutrition Examination survey. A second Finnish study with similar findings accompanied Stevens's report in the International Journal of Cancer, and suggets that there may be cause for concern. Register Guard (Eugene, OR), Jan. 16, 95; p 7A: Number of heart failures doubles, AP: 1982-92, heart disease death rate dropped 24.5%; number of cases of congestive heart failure doubled during roughly the same period. It killed 39,000 Americans in 1991, costs system $40 billion per year. Cancer is the biggest killer of women under 64, heart disease far surpasses cancer in women of ages 65-84.

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