Fleming D J, Jacques P F, Dallal G E, Tucker K L, Wilson P W, Wood R J
Division of Biostatistics, Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
Am J Clin Nutr. 1998 Apr;67(4):722-33. doi: 10.1093/ajcn/67.4.722.
Epidemiologic studies have found a relation between body iron stores and risk of chronic disease. Iron-absorption studies from single meals have shown that many dietary factors can influence nonheme-iron bioavailability. However, little is known about the association of these dietary factors with iron stores in free-living elderly populations. To address this question, we investigated the consumption of various dietary components and iron stores in an elderly sample of The Framingham Heart Study participants. Serum ferritin was used as a measure of body iron stores in 634 free-living elderly (67-93 y of age), and dietary intake during the previous year was assessed by a food-frequency questionnaire. The relation between serum ferritin and various dietary factors was assessed by multiple regression analysis. Subjects whose ferritin concentrations might be pathologically elevated because of infection, inflammation, liver disease, or genetic hemochromatosis were excluded from the analysis. After we controlled for sex, age, body mass index, total energy intake, smoking, and use of aspirin and other medications known to affect blood loss, we found five significant dietary factors associated with iron stores. Heme iron, supplemental iron, dietary vitamin C, and alcohol were positively associated with serum ferritin, whereas coffee intake had a negative association. As expected, sex was a strong predictor of serum ferritin-women having significantly lower mean concentrations than men. However, age was not related to serum ferritin in our elderly population. Our results suggest that in typical Western-style diets, a small number of dietary factors probably modulate the bioavailability of dietary iron and influence the accumulation of iron stores.
流行病学研究发现体内铁储备与慢性病风险之间存在关联。对单餐铁吸收的研究表明，许多饮食因素会影响非血红素铁的生物利用度。然而，对于这些饮食因素与自由生活的老年人群铁储备之间的关联却知之甚少。为解决这一问题，我们在弗雷明汉心脏研究参与者的老年样本中调查了各种饮食成分的摄入量和铁储备情况。血清铁蛋白被用作衡量634名自由生活的老年人（年龄在67 - 93岁之间）体内铁储备的指标，通过食物频率问卷评估前一年的饮食摄入量。通过多元回归分析评估血清铁蛋白与各种饮食因素之间的关系。因感染、炎症、肝脏疾病或遗传性血色素沉着症导致铁蛋白浓度可能病理性升高的受试者被排除在分析之外。在我们控制了性别、年龄、体重指数、总能量摄入、吸烟以及使用已知会影响失血的阿司匹林和其他药物后，我们发现了五个与铁储备相关的重要饮食因素。血红素铁、补充铁剂、饮食中的维生素C和酒精与血清铁蛋白呈正相关，而咖啡摄入量呈负相关。正如预期的那样，性别是血清铁蛋白的一个强有力的预测因素——女性的平均浓度明显低于男性。然而，在我们的老年人群中，年龄与血清铁蛋白无关。我们的结果表明，在典型的西式饮食中，少数饮食因素可能调节饮食中铁的生物利用度并影响铁储备的积累。
