Cross Amanda J, Harnly James M, Ferrucci Leah M, Risch Adam, Mayne Susan T, Sinha Rashmi
Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Blvd, Rockville, MD, 20852.
Food Nutr Sci. 2012 Jul 1;3(7):905-913. doi: 10.4236/fns.2012.37120.
Animal studies have demonstrated that iron may be related to carcinogenesis, and human studies found that heme iron can increase the formation of -nitroso compounds, which are known carcinogens.
One of the postulated mechanisms linking red meat intake to cancer risk involves iron. Epidemiologic studies attempt to investigate the association between heme iron intake and cancer by applying a standard factor to total iron from meat. However, laboratory studies suggest that heme iron levels in meat vary according to cooking method and doneness level. We measured heme iron in meats cooked by different cooking methods to a range of doneness levels to use in conjunction with a food frequency questionnaire to estimate heme iron intake.
Composite meat samples were made to represent each meat type, cooking method and doneness level. Heme iron was measured using atomic absorption spectrometry and inductively coupled plasma-atomic emission spectrometry.
Steak and hamburgers contained the highest levels of heme iron, pork and chicken thigh meat had slightly lower levels, and chicken breast meat had the lowest.
Although heme iron levels varied, there was no clear effect of cooking method or doneness level. We outline the methods used to create a heme iron database to be used in conjunction with food frequency questionnaires to estimate heme iron intake in relation to disease outcome.
动物研究表明铁可能与致癌作用有关，而人体研究发现血红素铁可增加亚硝基化合物的形成，亚硝基化合物是已知的致癌物。
红肉摄入与癌症风险之间的一种假定机制涉及铁。流行病学研究试图通过对肉类总铁量应用一个标准因子来调查血红素铁摄入量与癌症之间的关联。然而，实验室研究表明，肉类中的血红素铁水平会因烹饪方法和熟度水平而有所不同。我们测量了用不同烹饪方法烹制至一系列熟度水平的肉类中的血红素铁，以便与食物频率问卷一起使用，来估计血红素铁摄入量。
制备复合肉类样本以代表每种肉类类型、烹饪方法和熟度水平。使用原子吸收光谱法和电感耦合等离子体原子发射光谱法测量血红素铁。
牛排和汉堡包中的血红素铁含量最高，猪肉和鸡大腿肉的含量略低，鸡胸肉的含量最低。
尽管血红素铁水平有所不同，但烹饪方法或熟度水平并无明显影响。我们概述了用于创建血红素铁数据库的方法，该数据库将与食物频率问卷一起使用，以估计与疾病结局相关的血红素铁摄入量。
