彝族成年男子膳食中铁、锌、钙的生物利用研究

目的:评价彝族成年男子膳食中铁、锌和钙的生物利用情况,为防治该人群矿物质缺乏病提供基础信息。方法:以代谢平衡法于现场对12名20~22岁彝族世居地的成年男子进行14d试验。试验开始,收集对象空腹血,检测血红蛋白、红细胞压积、血清铁蛋白、血浆锌和钙浓度。试验期间,收集4~12d试验膳及摄入试验膳后排出的粪便和尿样。应用火焰原子吸收法测定膳食、粪便和尿中三种矿物质的含量,分别计算出它们的表观吸收率、平衡状态和表观利用率。结果:彝族成年男子代表性膳食中铁、锌和钙的表观吸收率(%)分别为15.8±6.2、24.5±4.1、32.3±9.7;表观利用率(%)分别为1.9±5.7、12.8±4.3、5.5±15.9。平衡试验显示铁,锌,钙均为平衡,但钙的变动范围较大。结论:膳食中铁、锌摄入量能满足试验对象的需要量,而钙的摄入量则不能满足其需要量。三种矿物质的表观吸收率与表观利用率基本上与我国正常人相同。建议彝族居民增加钙含量高的食物摄入量,以预防钙缺乏。

STUDY ON BIOAVAILABILITY OF DIETARY IRON, ZINC AND CALCIUM IN MALE ADULTS OF YI NATIONALITY

Objective: To study the absorption and utilization of dietary iron, zinc and calcium of male adults of Yi nationality, for basic information to prevent and cure diseases related to mineral deficiencies. Method: Twelve young men aged between 20 and 22 from the region lived by Yi nationality were studied in 14 d period with metabolic balance technique. At the beginning of study, their fasting blood hemoglobin and hematocrit, serum ferritin, plasma zinc and calcium concentration were deteimined. During the 4-12 d of the study, experimental diet, subsequent feces and urine samples were also collected for determining the contents of iron, zinc and calcium by flame atom absorption spectrum method, and then apparent absorption rate, apparent utilization rate and metabolic balance of these minerals were calculated. Results: The apparent absorption rate of iron, zinc and calcium was (15.8±6.2)%, (24.5±4.1)% and (32.3±9.7) % and the apparent utilization rate was (1.9±5.7)%, (12.8±4.3)% and (5.5±15.9)% respectively. The metabolic study showed iron balance, and zinc balance, but calcium balance was variable. Conclusion: The intakes of iron and zinc from the diet can meet the requirements, but calcium cannot. More intakes of foods rich in calcium are recommended for Yi nationality.