成年人膳食矿物质摄入与机体矿物质营养状况的关系初探

目的探讨膳食矿物质摄入与机体矿物质营养状况的关系。方法采用24 h回顾法调查研究对象3 d膳食,计算其营养素摄入量,并进行评价;同时收集研究对象血液和尿液,测定其中矿物质钙、镁、铁、锌、铜、锰、硒水平。结果研究对象中男性锌、硒、维生素B1(VB1)、维生素B2(VB2)和维生素C(VC)摄入不足的比例分别为35.8%、19.4%、71.6%、61.2%和70.1%;女性分别为6.8%、27.0%、59.5%、36.5%和36.5%。男性膳食钙、镁、铁、铜、锰和维生素E的平均摄入量分别为AI的67.8%、91.5%、140.8%、101.0%、187.4%和199.1%,膳食钙存在摄入不足;女性膳食钙、镁、铁、铜、锰和维生素E的平均摄入量分别为AI的56.2%、75.4%、92.9%、94.0%、157.7%和181.7%。膳食铁与血浆铁含量存在正相关关系(r=0.263,P<0.05),膳食铜与尿铜之间存在负相关关系(r=-0.298,P<0.05),膳食中其他元素均与该元素在血浆、红细胞和尿液中含量无相关性(P>0.05)。结论调查对象存在膳食营养素摄入不足,应适当补充微量营养素。膳食矿物质摄入与机体该元素水平之间无直接相关关系。     

哺乳期农村乳母乳汁无机元素含量的变化

目的了解哺乳期人乳无机元素含量的变化及其与乳母膳食的关联。方法采用横断面调查方法,收集55名陕西省澄城县农村健康乳母清晨乳样,利用原子吸收分光光度法测定乳汁钙、镁、铁、锰、锌和铜的浓度。采用24小时回顾法进行连续3天膳食调查,计算膳食营养素的摄入量。结果农村乳母乳汁中镁、锌、铜浓度随哺乳期延长明显降低,铁浓度随哺乳期延长而上升。乳母膳食钙摄入量约为钙膳食参考摄入量(DRI)1/3,膳食无机元素的摄入量与人乳相应元素之间无明显相关性。多因素分析表明,乳汁中钙与镁、铁与铜、锰与锌均呈正相关,钙分别与乳脂、铁、锌呈负相关。结论随哺乳期时间延长,成熟乳中镁、锌、铜浓度降低而铁浓度增加,乳母膳食钙的摄入严重不足,乳汁各元素与膳食相应元素之间无关联。     

乳母膳食与乳汁中矿物质含量研究

目的探讨膳食矿物质摄入水平及对乳汁矿物质含量的影响。方法选择婴儿月龄在30天~50天母乳喂养的健康乳母为调查对象,共56人,年龄23~35岁。于产后30天由专人进行入户调查。采用24小时回顾法,记录调查对象每餐摄入食物的种类和数量,并同时采集乳汁,用火焰原子吸收光度法测其钙、铁、锌、镁、铜、锰的含量。结果济南市乳母膳食中禽蛋摄入较高149g,豆类较低14g。与营养素推荐摄入量(RNI)比较,膳食能量摄入偏低(77.5%)。膳食矿物质铜、铁、锰、镁的摄入量均达到RNI的90%,钙摄入量较低,仅为RNI的62.5%。乳汁中钙、铁、锰、镁、铜、锌含量分别为0.39g/L、1.35mg/L、17.5μg/L、36mg/L、0.33mg/L、2.18mg/L。膳食矿物质摄入量与乳汁中矿物质含量的相关性分析结果显示,膳食钙、锌、锰的摄入量与乳汁中含量显著相关(P<0.01)。结论济南市乳母膳食组成中禽蛋摄入较高,豆类摄入偏低,膳食钙、维生素B1摄入不足。     

惠州学院164名在校女生膳食营养状况调查

目的了解女大学生膳食营养状况,为开展高校膳食营养教育提供参考。方法采用24h膳食记录法和查帐法对惠州学院164名随机抽样的女大学生进行连续3d的膳食调查,通过实验室检查进行营养状况评价。结果惠州学院在校女生能量摄入量只占RNI的73%,钙摄入量只占RNI的42%;碳水化合物、维生素B1、维生素B2、铁、锌摄入量不足;动物性食品偏少;血液钙、镁、铁、铜、锌浓度偏低。结论惠州学院女生膳食结构不合理,应调整膳食结构,增加动物性食物的摄入,提高膳食能量、钙、维生素B1、维生素B2、微量元素的摄入量。     

膳食矿物质与骨密度关系调查

目的 研究老年人膳食中矿物质含量对骨密度（BMD）的影响，探讨防治老年骨质疏松的措施。方法 对309例60岁以上老人进行了膳食调查及健康检查。结果 老年女性骨矿物质含量（BMC）和骨密度（BMD）显低于男性。健康老人平均每日摄入钙、锰、铜、硒的量男性均显高于女性。OP患与同性别健康老人每日矿物质摄入量相比，OP组钾钙、镁、铁、锰、锌、磷、来源于奶的钙（简称奶钙）、硒摄入量均显低于同性别健康老人组，BMD与钾、钙、镁、锌、铜、磷、硒、奶钙摄入量和钙磷比值均呈显正相关。结论 膳食矿物质与BMD存在一定的关系，膳食钾、钙、锌等摄入量不足可能导致BMD降低。     

山东省农村育龄妇女代表性膳食下铁、锌、钙吸收率分析

目的:研究山东省农村育龄妇女代表性膳食下铁、锌、钙的吸收率,以及膳食因素对它们吸收利用的影响。方法:用代谢平衡法,使用原子吸收分光光度计(AAS)测定膳食与粪便的铁、锌、钙,计算铁、锌、钙的吸收率。同时测定影响铁、锌、钙吸收的因子:膳食脂肪、蛋白、植酸、纤维素和VitC的含量,计算日平均摄入量,将其结果与我国育龄妇女每日推荐膳食营养素摄入量(RNI)进行比较。结果:铁、锌、钙的吸收率分别为8·26%、21·48%、47·94%,铁的平均日摄入量为13·77mg,占RNI的68·85%,远低于推荐量,锌的平均日摄入量为15·43mg,占RNI的102·87%,高于推荐量,钙的平均日摄入量为409·38mg,占RNI的51·17%,远低于推荐量。蛋白质和VitC的日摄入量分别为65·70g与34·20mg,占RNI的82·12%~109·50%和34·20%,低于推荐量。脂肪、植酸和膳食纤维的摄入量较高。结论:在蛋白质和抗坏血酸的日摄入量较低,脂肪、植酸和膳食纤维的摄入量较高的条件下,铁吸收率较低,铁营养缺乏,锌营养尚可,钙摄入量显著低于RNI,显示钙摄入严重不足。     

1341例孕妇孕中期膳食营养状况调查

目的 了解武汉市武昌区孕妇孕中期营养摄入状况,为制定孕妇合理膳食干预措施保障胎儿生长发育提供依据.方法 采用回顾性调查方法,记录孕妇在被调查前24 h内所摄入的各种食物种类和数量,录入营养分析软件.结果 能量及蛋白质、脂肪、碳水化合物的摄入能基本满足机体需要,实际摄入量分别占推荐摄入量（RNI）的88.00％、107.04％、96.66％、83.44％;铁、锌摄入量分别占RNI的96.32％、86.91％;钙,镁,维生素A、C、B1、B2摄入不足的人数比例超过50％;胆固醇摄入超过可耐受最高摄入量（UL）的人数比例为82.18％;饱和脂肪酸、不饱和脂肪酸的摄入量分别占脂肪酸摄入总量的29.67％和70.33％;早中晚三餐的能量摄入配比为22.08∶38.28∶39.64.结论 孕妇对孕期营养方面的认知存在不足.矿物质铁、锌摄入充足,钙和镁摄入不足;维生素摄入不足,胆固醇摄入过量;脂肪酸配比不合理,早中晚三餐配比不合理.必须从扩大社会宣传力度、壮大营养保健专业队伍入手,提高孕妇对合理的膳食营养摄入认识.     

内蒙古民族大学蒙古族学生膳食营养状况调查

目的了解蒙古族大学生的膳食结构和营养状况,为合理营养提供科学依据。方法采用称重记账法和膳食记录法进行5d膳食调查,依据《中国居民膳食营养素参考摄入量(DRIs)》中18岁以上中等体力劳动的推荐摄入量(RNI)或适宜摄入量(AI)进行比较评价。结果蒙古族男女学生蛋白质、铜、硒、维生素PP摄入充足,男生铁、锌、维生素A、维生素B1、维生素B2均达到和超过推荐摄入量(RNI)或适宜摄入量(AI)。蒙古族男女学生膳食中存在的共性问题是膳食纤维、维生素C及钙不足,脂肪类食物来源比例不合理。蒙古族女生膳食蛋白质质量尚可,但数量不足,膳食中能量、铁、锌、维生素B2摄入不足,维生素A和维生素B1摄入严重不足;蒙古族男生早餐能量摄入不足。结论蒙古族男女大学生膳食结构均不合理,应对学生加强营养知识的教育。     

应用双份饭法研究测定河南省某高校学生膳食钙、铁、锌摄入水平

[目的]了解河南省某高校学生膳食钙、铁、锌的摄入水平。[方法]随机抽取在校大学生20人,采用双份饭法收集被调查对象3d内摄入的所有食物,实验室测定钙、铁、锌的含量。[结果]大学生膳食钙、铁、锌的平均摄入量分别为510.71mg/d、29.14mg/d、13.57mg/d。其中男性每日锌膳食摄入量明显高于女性(P=0.01)[结论]大学生膳食钙的摄入明显偏低,应引起相关部门的重视,采取综合措施,开展多种形式的营养知识宣传教育,引导学生合理膳食,及时纠正不合理的膳食结构,并采取适当的措施进行营养干预。     

孕妇营养状况与胎儿生长发育关系的探讨——Ⅱ.孕期母血中某些生化指标的改变与脐血中相应指标以及某些膳食因素的关系

作者测定了101名正常孕妇不同孕期血中及胎儿脐血中血清总蛋白、白蛋白、运铁蛋白、血红蛋白、钙、铁、锌,铜的含量,并在采血的同时作了膳食调查。结果提示,随着妊娠的进展,母体血清总蛋白、血清铁、锌和血红蛋白含量下降。如将母血中上述指标与胎儿脐血中相应指标的含量作单相关分析,可见孕后期母血中铁、钙和锌与脐血中含量呈正相关。用逐步回归分析,与母血总蛋白关系最密切的膳食因素为总热量;与血钙、血锌、血铁关系最密切的膳食因素分别为总钙摄入;动物性食品量;肉、鱼类食品与维生素C摄入量,血红蛋白则与食物中总热能和血清铁关系最大。单相关分析指出血清钙与膳食中总蛋白质摄入,动物性钙,乳类食品摄入量也呈正相关。     

Equilibrium intakes of calcium and magnesium within an adequate and limited range of sodium intake in human

In the previous analysis of our human mineral balance studies, we demonstrated positive correlations between the balances of calcium (Ca) and magnesium (Mg) and sodium (Na) intake in the range of 3.06 and 4.06 g/d or 43.71 and 96.40 mg/kg body weight (BW)/d, but there was no correlation between Na intake and Na balance. This suggested that the balances of Ca and Mg are affected by Na intake. Therefore, in the current study, we recalculated equilibrium intakes for Ca and Mg when balances of their intakes and outputs were equal to zero within the above Na range to reduce the effects of Na intake. From 1986 to 2000, 90 volunteers (10 male, 80 female; age 18 to 28 y) took part in 9 mineral balance studies. The balance periods ranged from 8 to 12 d, with adaptation periods of 2 to 4 d. The dietary intakes of Ca and Mg ranged from 294 to 719 and 154 to 334 mg/d, or from 4.83 to 15.07 and 2.44 to 6.42 mg/kg BW/d, respectively. Intake of Ca significantly correlated with Ca balance (r2 = 0.268; p < 0.0001). When the balance was equal to zero, the mean value and upper limit of the 95% confidence interval for the regression equation between intake vs. balance were 10.072 and 10.660 mg/kg BW/d, respectively. Mg intake correlated significantly with Mg balance (r2 = 0.141, p = 0.003). When the balance was equal to zero, the mean value and upper limit of the 95% confidence interval for the regression equation between intake and balance were 4.078 and 4.287 mg/kg BW/d, respectively.     

Balance of magnesium positively correlates with that of calcium

BACKGROUND AND OBJECTIVE: In a prior study, we showed no significant relationship between intake and balance of magnesium (Mg). Subsequent further investigation disclosed that intakes of both Ca and P were positively correlated with their respective balances, whereas intake of Mg did not show any significant correlation with Mg balance. In this paper, we show positive correlations between intake of Mg and balances of both Ca and P. METHODS AND RESULTS: Using these correlations, the mean value and upper limit of the 95% confidence interval (from the regression equation between Mg intake and either the balances of Ca or that of P, when each balance is equal to zero) were 4.584 and 4.802 (against Ca balance), 4.554 and 4.785 (against P balance) mg/kg BW/d, respectively. Balances of Mg and Ca correlated with each other.     

Estimated equilibrated dietary intakes for nine minerals (Na, K, Ca, Mg, P, Fe, Zn, Cu, and Mn) adjusted by mineral balance medians in young Japanese females

The present study sought to determine estimated equilibrated dietary intakes (EEDIs) for nine essential minerals: sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn), using data from 17 human mineral balance studies conducted from 1986 to 2007 (subjects=178). Among these studies, two used male subjects, two subjected some or all subjects to sodium restriction, and one study utilized a low protein diet; these subjects were not included in the present analysis. Consequently, data from 13 studies of young female subjects (n=131) consuming a standard diet were selected. Balance distribution medians for six of the minerals (Na, K, Mg, Fe, Zn and Cu) were positive, so the data were adjusted to set the medians of the balances to zero. Medians for the other minerals (Ca, P and Mn) were close to zero and were not adjusted. Intake and balance for each mineral were divided by body weight (BW), lean body mass (LBM), and standard body weight (SBW), which was calculated using height and standard body mass index (BMI=22), and EEDIs were calculated as the intercept of a simple regression equation. When relationships between intake and balance of a mineral were not significant in the regression equation, a significant regression equation comparing intake and balance of another mineral was used to calculate the intercept. Significant simple regression equations were not obtained from any of the three parameters of Na or Zn, or for two of the parameters of P; thus, K, Fe and Ca balances were used to determine the intercepts for Na, Zn and P, respectively. EEDIs for the minerals were: Na (67.9, 89.0, 62.5), K (39.5, 53.5, 37.4), Ca (11.0, 14.4, 10.1), Mg (4.18, 5.51, 3.86), P (18.7, 24.6, 17.3) (mg/kg BW/d, mg/kg LBM/d, mg/kg SBW/d), Fe (180, 237, 165), Zn (168, 241, 166), Cu (30.9, 42.6, 29.7), Mn (55.1, 72.1, 50.7) (μg/kg BW/d, μg/kg LBM/d, μg/kg SBW/d), respectively. These values are nearly identical to the mean dietary intakes.     

Zinc intake and status in Australian vegetarians

Vegetarians have a lower incidence of many chronic diseases than omnivores. However, vegetarian diets could potentially result in lower intakes of some minerals, particularly Zn. In a cross-sectional study, dietary Zn intake was measured using 12 d weighed records in ninety-nine vegetarians (ten vegans) aged 18-50 years and forty-nine age- and sex-matched omnivores. In men, the mean daily Zn intake and Zn density values were similar in omnivores, ovolactovegetarians and vegans, but in women they were significantly lower in vegetarians (mean intake 6.8 mg v. 8.4 mg in omnivores) and few achieved the recommended intake. Significantly more vegetarian than omnivorous women had a daily Zn intake < 6 mg (44% v. 13%). Mean serum Zn concentrations were similar in female omnivores and vegetarians, despite the differences in intake. However, omnivorous men had a lower mean serum Zn concentration (0.85 microgram/ml v. 0.95 microgram/ml) and more subjects had levels below the reference range of 0.72-1.44 micrograms/ml than ovolactovegetarians (P < 0.01). Overall more women than men had low Zn concentrations; and these women generally had intakes below 6 mg/d. There was a significant correlation between serum Zn concentration and dietary Zn density in vegetarians, especially females (P < 0.001), but not in omnivores. Ovolactovegetarians did not have a significantly greater risk of low Zn status than omnivores.     

1992年中国总膳食研究——常量和微量元素

通过测定混合膳食中１０种常量和微量元素含量，评价中国南、北四大地区人群每日膳食中常量和微量元素的摄入状况，并报道了膳食中各元素摄入量以及不同年龄组和春秋两季膳食中各元素摄入量的变化情况。结果表明：儿童膳食中不同程度地存在钙、磷、钾、镁、锌、硒和铜的偏低；成人膳食中钙、钾和锌摄入明显不足，其余７种元素均接近或达到推荐供给量水平，但地区差异较大。本文对钙磷比，钾钠比以及铁和铜与缺铁性贫血之间的关系进行了讨论。     

Trace element status of PKU children ingesting an elemental diet

We assessed the trace metal status of 10 children (3.5 to 13.3 yr) with phenylketonuria (PKU) who were successively treated for at least 6 months with a semi-synthetic formula restricted in phenylalanine, then for 6 months with a reformulated formula. The reformulated product contained higher concentrations of magnesium (Mg), potassium (K), phosphorus (P), selenium (Se), and zinc (Zn) and lower concentrations of calcium (Ca), sodium (Na), and unsaturated fats. Diet records, blood samples, and urine specimens were collected from each subject. Mean intakes of Mg, K, and Zn increased significantly when subjects were switched to the reformulated product. The subject's mean intakes of Se (for all age groups) and Zn (children 11 to 14 yr old) were below 67% of recommended intakes while they were ingesting the original formula. The mean trace metal concentrations of urine, blood, and serum did not differ significantly during the two periods. Mean serum Zn, Se, and Cu concentrations of the subjects were less than those reported for normal children. Significant negative correlations were obtained between serum Zn concentrations and the molar ratio of dietary (Ca + P):Zn, and the molar ratio of dietary Fe:Zn. No significant differences in mean urinary Cu and Zn excretion (mg/g creatinine) were observed in subjects after they were changed to the reformulated product. Individuals whose primary source of energy and protein is derived from semi-synthetic elemental diets are especially at risk for multiple trace element deficiencies.     

Fima Lifshitz,MD, FACN,Named New Editor of the Journal of the American College of Nutrition

Both zinc (Zn) and magnesium (Mg) are widely used as nutritional supplements and the possibility was considered that Zn may interfere with the absorption of Mg, similar to previously reported results [1,2] obtained with the same dose of supplemental Zn on the absorption of calcium (Ca).

Mg absorption studies and metabolic balances of Mg and of Zn were carried out in three groups of adult males in a metabolic research unit during the intake of supplemental doses of 142 mg Zn as Zn sulfate (ZnSO4) during Ca intakes of 230, 500 and 800 mg/day.

The Zn intake of 142 mg/day decreased the Mg balance and Mg absorption only during the 500 mg Ca intake compared to control values. However, the overall effect of the high Zn intake of the three groups combined, regardless of the Ca intake, was a highly significant decrease of Mg absorption and of the Mg balance.

Zn supplements of 142 mg/day decreased Mg absorption and the Mg balance significantly during all Ca intakes for the three groups combined.     

Calcium and magnesium dietary intakes and plasma and milk concentrations of Nepalese lactating women

Dietary calcium and magnesium intakes of 26 Nepalese lactating women were determined from analysis of 24-h duplicate food and beverage composites. In addition, blood, urine, and milk samples were collected. The mean Ca intake of these Nepalese mothers, 482 +/- 249 mg/d, was less than half that of American lactating women yet the Ca concentration of the milk was similar for the two groups of women. The Nepalese mothers appeared to maintain milk Ca concentrations by an increase in bone resorption as demonstrated by an elevated excretion of hydroxyproline. The Nepalese women had a mean Mg intake of 353 +/- 28 mg/d. Two locally available foods considered special for lactating women, jwano and gundruk, were examined for nutrient content and found to contain high concentrations of Ca and Mg. Increased consumption of these locally grown foods could add substantially to the Ca and Mg intakes of these lactating women.     

安徽农民膳食中无机元素全年摄入量调查

对歙县、庐江、凤阳、利辛四县部分农户的Ｋ、Ｎａ、Ｃａ、Ｍｇ、Ｐ、Ｆｅ、Ｚｎ、Ｃｕ、Ｍｎ９种无机元素摄入量进行为期一年的调查，显示Ｋ、Ｃａ、Ｍｇ、Ｚｎ摄入量不足，Ｃａ尤为明显。Ｃａ、Ｚｎ、Ｃｕ、Ｆｅ、Ｍｎ的食物来源以植物性食物为主，吸收率低，应适当增加Ｃａ及微量元素含量高且易吸收的动物性食物的摄取量。江淮地区钠摄入量过高，应降低食盐的摄取量。