中国经济网北京10月28日讯 （记者 段丹峰）北京时间26日晚，世界卫生组织旗下的国际癌症研究机构在发布的最新报告中，将培根、火腿、香肠等加工肉制品列为致癌物，因有“充分证据”表明其可能导致肠癌。报告称，每天食用50克的加工肉制品会使患结直肠癌的概率增加18%。此外，牛肉、羊肉、猪肉等“红肉”也有致癌可能。
　　对此，世界卫生组织国际癌症研究机构Nicolas Gaudin博士在接受中国经济网记者独家专访时表示，国际癌症研究机构工作组分析了大约800份有关肉类饮食与癌症之间关联的研究，从而编写出这份报告。结果显示，食用加工肉制品除了与结直肠癌有关联之外，也与胰腺癌和前列腺癌的发生有一些关联。
　　Nicolas Gaudin博士表示，肉类本身由血红素铁等多种成分构成，同时也会在烹饪和加工过程中产生另外一些化学物质，例如，肉类在加工过程中会产生N-亚硝基化合物、多环芳烃等多种致癌物质，牛肉、羊肉、猪肉等“红肉”或者加工肉制品在烹饪过程中也会产生杂环芳香胺等多种多环芳烃化合物，这些物质也会存在于其他食物或者被污染的空气中。这些化学物质有些已经被确认为致癌物，也有些是疑似致癌物，尽管人们到目前为止还不能确定加工肉制品是如何增加癌症风险的。
　　国际癌症研究机构在报告中，把热狗、火腿、香肠、培根和牛肉干等肉类制品列为1A级“一类致癌物”，同在“一类致癌物”列表的还有烟草、砒霜、酒精、石棉和柴油发动机尾气等。就消费者个体而言，因平时食用加工肉制品的数量有限，患癌症的概率不大；但若食用更多，则风险上升，世卫报告称，每天食用50克的加工肉制品会使患结直肠癌的概率增加18%。牛肉、羊肉和猪肉等红肉类被归类为“疑似致癌物2A级”，和其在同一列表中的有草甘膦。2A级物质意味着可能对人体有致癌性，而1A级物质代表与癌症有明确关联。
　　据Nicolas Gaudin博士介绍，国际癌症研究中心将致癌物质依据其致癌危险分为四类。1类对人致癌；2A类对人很可能致癌；2B类对人可能致癌；3类对人的致癌性尚无法分类，即可疑对人致癌；4类对人很可能不致癌。
　　Nicolas告诉记者，此次报告即是将加工肉制品被列入1类致癌物中，牛肉、羊肉、猪肉等红肉则被列入2A类，对人很可能致癌。国际癌症研究机构的这项评估再次确认了世界卫生组织在2002年的一项建议：人们应该有节制地摄入加工肉制品来降低患上结直肠癌的风险。
　　此外，Nicolas还表示，国际癌症研究机构致力于研究可致癌物质以及衡量这些致癌物质的危害程度，并不涉及到相关健康建议，国家政府和世界卫生组织则专门负责制定健康营养方案。虽然其他一些膳食指南也提出了“红肉”和加工肉制品的建议限制摄入量，但这些建议大部分集中于减少肉类中脂肪和钠的摄入量，而脂肪和钠是导致心血管疾病和肥胖的主要危险因素。
　　对此，Nicolas博士建议，那些比较担心癌症的人群可以考虑减少他们红肉和加工肉制品的摄入，直到最新的专门针对癌症的指导建议进一步制定出来。
　　据了解，世卫报告还特别解释，“红肉”指的是所有哺乳动物的肌肉，包括牛肉、小牛肉、猪肉、羊肉、山羊肉和马肉。
　　而“加工肉制品”指经过盐腌、风干、发酵、烟熏或其他处理方式、用以提升口感或延长保存时间的任何肉类。
　　国际癌症研究机构是世卫组织下属机构，成立于1965年，主要进行有关癌症病因的研究。该机构将致癌物的风险分为“致癌、致癌可能性较高、可能致癌、致癌程度不确定和可能不致癌”五个级别。据称，来自10个国家的22名专家分析了大约800份有关肉类饮食与癌症之间关联的研究，从而编写出这份报告。这是国际癌症研究机构首次对肉类进行评估。这一机构没提出具体的政策建议，但“建议限制肉类的摄入”，尤其是加工肉制品。
　　以下内容为记者采访全文：
　　1. Q:As so far, is there any published study or evidence showing that red meat and processed meat intake is associated with cancer risk?
　　A:The IARC Working Group considered more than 800 different studies on cancer in humans (some studies provided data on both types of meat; in total more than 700 epidemiological studies provided data on red meat and more than 400 epidemiological studies provided data on processed meat).
　　2. Q:If there is, which specific category of cancer is related to each of the meat type?
　　A:Colorectal cancer, and to a lesser extent pancreas and prostate cancers
　　3.Q: As well-known, nitrite is a highly toxic substance and carcinogen and it can be used in the curing process of meat. Is this the reason why people think meat intake could be associated with cancer risk? And what is the recommended amount of nitrite to develop cured meat?
　　A:Meat consists of multiple components, such as haem iron. Meat can also contain chemicals that form during meat processing or cooking. For instance, carcinogenic chemicals that form during meat processing include N-nitroso compounds and polycyclic aromatic hydrocarbons. Cooking of red meat or processed meat also produces heterocyclic aromatic amines as well as other chemicals including polycyclic aromatic hydrocarbons, which are also found in other foods and in air pollution. Some of these chemicals are known or suspected carcinogens, but despite this knowledge it is not yet fully understood how cancer risk is increased by red meat or processed meat.
　　4. Q:There are five levels in the classification of carcinogen, such as proved carcinogen, suspected carcinogen, potential carcinogen and etc.. Than which level that red meat and processed meat could be classified under?
　　A: The IARC Classification contains 5 groups:
　　Group 1 Carcinogenic to humans
　　Group 2A Probably carcinogenic to humans
　　Group 2B Possibly carcinogenic to humans
　　Group 3 Not classifiable as to its carcinogenicity to humans
　　Group 4 Probably not carcinogenic to humans
　　Processed meat was classified as a Group 1 carcinogen, and red meat was classified as a Group 2A, probable carcinogen.
　　5. Q:If the consumption of both meat types is not a strong risk factor for cancer, than what is the recommended daily meat intake?
　　A: IARC is a research organization that evaluates the evidence available on the causes of cancer but does not make health recommendations as such. National governments and WHO are responsible for developing nutritional guidelines. This evaluation by IARC reinforces a 2002 recommendation from WHO that people who eat meat should moderate the consumption of processed meat to reduce the risk of colorectal cancer. Some other dietary guidelines also recommend limiting consumption of red meat or processed meat, but these are focused mainly on reducing the intake of fat and sodium, which are risk factors for cardiovascular disease and obesity. Individuals who are concerned about cancer could consider reducing their consumption of red meat or processed meat until updated guidelines related specifically to cancer have been developed.