Pabón de Rozo M, VanCampen D, Miller D D
Universidad Nacional de Colombia, Bogotá.
Arch Latinoam Nutr. 1986 Dec;36(4):688-700.
Two experiments were performed to examine the effects of various carbohydrates (fructose, lactose, corn starch, wheat starch and potato starch) on the utilization of iron, on Fe-depleted rats. These received a single meal that contained the test carbohydrate at a 60% level, labelled with 59Fe. The rest of the experiment the rats were fed a diet which contained glucose at a 60% level as the carbohydrate source. In both experiments rats were fasted overnight, and the dose was offered in the form of a morning meal. To assay for 59Fe, the animals were counted in a "Whole body counter" between two and four hours after dosing, and every day for the following 10 days. Percentage retention and absorption, as well as hemoglobin values were determined. In the first experiment, the replacement of glucose by fructose at a 60% level enhanced significantly iron absorption and retention. An increase in absorption and retention also occurred when glucose was replaced by lactose at a 60% level, but the difference was not statistically significant. Administration of 59Fe as an 59Fe-fructose chelate did not seem to have a significant effect on retention and absorption when compared to the effect of dosing with 59Fe adsorbed onto a fructose diet. This not rule out the possibility that chelation is the mechanism responsible for the enhancing effect of fructose on iron utilization. The complex could have been formed in the stomach, resulting in a significant absorption for both the 59Fe-labelled meal and the 59Fe-carbohydrate complex-labelled meal. In the second experiment, administration of a meal that contained either of the starches resulted in a reduction on retention and absorption of 59Fe. The decrease, however, was statistically significant only for cooked corn starch, wheat starch and cooked wheat starch. The effect of cooking was to reduce even more the retention and absorption of 59Fe, but this reduction was statistically significant only for corn starch. The depressing effects of starches on iron retention and absorption are quite relevant to human nutrition. In the developing countries, diets are generally high in cereal products - often whole grain cereals - and low in animal products. The inhibitory effects of cereals on iron absorption have been traditionally attributed to the presence of phytates and fiber, but the data herein presented suggest that high intakes of starches may be inhibitory as well.
进行了两项实验，以研究各种碳水化合物（果糖、乳糖、玉米淀粉、小麦淀粉和马铃薯淀粉）对缺铁大鼠铁利用的影响。给这些大鼠喂食一顿含有60%受试碳水化合物的单餐，该餐用59Fe标记。在实验的其余时间，给大鼠喂食一种含有60%葡萄糖作为碳水化合物来源的饮食。在两项实验中，大鼠均隔夜禁食，剂量以早餐形式提供。为了测定59Fe，在给药后两到四小时之间以及接下来的10天每天，用“全身计数器”对动物进行计数。测定了保留率、吸收率以及血红蛋白值。在第一个实验中，用60%的果糖替代葡萄糖可显著提高铁的吸收和保留。当用60%的乳糖替代葡萄糖时，吸收和保留也有所增加，但差异无统计学意义。与用吸附在果糖饮食上的59Fe给药的效果相比，以59Fe-果糖螯合物形式给药59Fe似乎对保留和吸收没有显著影响。这并不排除螯合作用是果糖对铁利用增强作用的机制的可能性。该复合物可能在胃中形成，导致59Fe标记餐和59Fe-碳水化合物复合物标记餐都有显著吸收。在第二个实验中，喂食含有任何一种淀粉的餐食会导致59Fe的保留和吸收减少。然而，这种减少仅对熟玉米淀粉、小麦淀粉和熟小麦淀粉有统计学意义。烹饪的效果是进一步降低59Fe的保留和吸收，但这种降低仅对玉米淀粉有统计学意义。淀粉对铁保留和吸收的抑制作用与人类营养密切相关。在发展中国家，饮食通常富含谷物产品——通常是全谷物谷物——而动物产品含量低。谷物对铁吸收的抑制作用传统上归因于植酸盐和纤维的存在，但本文提供的数据表明，高淀粉摄入量也可能具有抑制作用。
