锌膳食推荐量控制

锌的膳食推荐许可量过去是以代谢平衡资料来计算的，目前所采用的最佳方法是阶乘法。应用锌动力学方法及与膳食和生理功能的关系将更有帮助。将来的ＲＤＡＳ应至少提供低，中和高三个层次的生物利用度。     

锌的膳食参考摄入量研究进展

锌是人体必需微量元素,近年来膳食锌及锌补充剂与健康的关系备受关注。虽然我国人群锌营养状况显著改善,但各年龄段仍存在不同程度的缺锌。本文在我国研究数据的基础上,探讨了锌吸收率、锌营养状况评价、母乳锌水平以及可耐受最高摄入量等方面的研究进展,并比较了其他国家锌的推荐摄入量,为2023版锌膳食参考摄入量修订提供借鉴和参考依据。     

锌膳食推荐量探讨

锌的膳食推荐许可量（ＲＤＡｓ）过去是以代谢平衡资料来计算的，目前所采用的最佳方法是阶乘法。应用锌动力学方法及与膳食和生理功能的关系将更有帮助。将来的ＲＤＡｓ应至少提供低、中和高三个层次的生物利用度。本文还讨论健康人群通常摄锌量与ＲＤＡ及与其他锌膳食推荐量之间的差异     

5～6岁儿童锌代谢与膳食锌供给量的研究

采用锌代谢平衡法，测定１１名锌营养正常的学龄前儿童在平衡膳食干预前后锌营养有关指标及锌代谢。结果提示，经过三周平衡膳食干预，粪锌、尿锌及体表锌排出量与膳食锌摄入量呈显著正相关，粪锌、尿锌排出量随膳食锌摄入量的显著增加而增加，差异显著（Ｐ＜０．０５），锌代谢确实达到一稳定水平，其锌吸收量即为他们的锌需要量，平均为１．８４±０．４７ｍｇ／ｄ。如果锌吸收率以２０％计，则锌膳食供给量为９．２３±２．３５ｍｇ／ｄ。在锌代谢研究中首次测定在自然状态下儿童体表及头发排锌量，平衡膳食条件下分别为０．２７±０．０９ｍｇ／ｄ、５．２６±２．４９μｇ／ｄ。体表排锌量占锌总排出量的５％，仅次于粪锌排出量，占第二位，提示在锌需要量及膳食锌供给量研究中不可忽视这部分锌的损失。     

8～10岁单纯性肥胖儿童和正常儿童膳食锌调查

微量元素锌是维持机体正常生理功能和体内环境正常生化代谢所必需的元素，锌几乎涉及生物体所有细胞代谢，参与３００多种酶的组成。我们测定了５０名８～１０岁肥胖儿童及５０名正常儿童的膳食锌含量，以期观察哈尔滨市单纯性肥胖儿童与正常的儿童锌营养状况与生长发育的关系，现报告如下。１　对象与方法１１　调查对象：由哈尔滨市５所小学８～１０岁的儿童５２００名，按ＷＨＯ推荐的身高、体重判断，筛选出５０名单纯性肥胖儿童（排除有家族性肥胖史、体内激素代谢紊乱和其它疾病引起的继发性肥胖）及５０名正常发育的儿童为实验对象…     

山东农村典型膳食儿童人体锌吸收率研究

目的研究山东农村典型膳食锌(Zn)在农村儿童人体吸收率及Zn吸收相关营养素的日摄入量。方法受试者为4～6岁身体健康的农村儿童。标记稳定性同位素67Zn3.0mg,晚餐前一次经口给予,采用原子吸收法(AAS)和热电离质谱(TIMS)分别检测膳食和粪便中总锌含量与67Zn/68Zn比值,计算锌的吸收率,并对膳食铁、钙、脂肪、蛋白、植酸、纤维素和维生素C(VC)含量测定,将结果与我国儿童日推荐膳食营养素摄入量(RNIs)比较。结果锌的吸收率为(12.94±3.32)%,锌的平均日摄入量为11.16mg,占RNI的96.7%,蛋白质和抗坏血酸的日摄入量分别为31.2g与13.3mg,占RNI的62.4%和19.0%。结论在目前山东农村的膳食模式下,儿童体内锌的吸收率偏低,蛋白质和抗坏血酸的日摄入量不足。     

应用稳定性同位素^70锌中子活化法对缺锌儿童膳食锌吸收率的测定

本文以5—7岁整托幼儿园12名缺锌儿童为实验对象,实验前其发锌平均含量为:73.5±19.0ppm 锌儿童随机分为三组:A、锌摄入量6.1mg/日、B、10mg/日和C38.1mg/日。应用稳定性同位素~(70)锌中子活化分析法对三种膳食锌摄入量儿童,作了锌吸收率分别为:29.6±16.7％、33.9±6.8％、和23.1±2.5％。结果说明:①在理想的平衡膳食条件下锌的吸收率最高;②强化硫酸锌达到一定量(C组)会降低锌的吸收率。本文还对应用稳定性同位素~(70)锌中子活化法测定人体膳食锌吸收率产生误差的条件进行了分析。     

膳食胡萝卜素摄入量与皮肤类胡萝卜素水平的关系

[目的]探讨人群中膳食胡萝卜素摄入量与皮肤类胡萝卜素水平的关系。[方法]选取上海某社区110名健康成年人作为研究对象,分别运用共振拉曼散射光谱法测定研究人群皮肤类胡萝卜素,观察皮肤类胡萝卜素水平,同时进行体格检查和膳食营养调查。[结果]①膳食胡萝卜素摄入量无性别差异;皮肤类胡萝卜素女性高于男性,差别有统计学意义(P<0．001)。②膳食中的胡萝卜素摄入量与皮肤类胡萝卜素水平呈正相关,控制年龄、性别和体质指数(BMI)后这种相关性仍然存在(P<0．05)。③多元回归分析显示男性皮肤类胡萝卜素水平受膳食纤维摄入量的影响(P<0．001);女性还受膳食中的维生素C、脂肪、能量等摄入量的影响(P<0．05)。[结论]食物中胡萝卜素、膳食纤维、脂肪、维生素C摄入量与皮肤类胡萝卜素水平有一定的关联。     

膳食植酸与锌生物利用研究进展

植酸即肌醇六磷酸。英文名为Phytate。主要存在于植物当中,其中以豆类种子、麸糠和谷物胚芽中含量最高,在谷物中含量约1.0-5.0％,并且植酸含量随植物成熟而增加。植酸常以Ca-Mg-K植酸盐形式存在,不同的植物中其化合物形式不同,在玉米中主要以水溶态存在于胚芽中;在豆科主要以蛋白质结合型存在。由于植酸有较强的络合能力,可与包括锌在内的二价金属离子络合,从而降低这些元素的生物利用率(?)目前。我国及许多发展中国家膳食仍是以粮     

学前儿童膳食植酸摄入量及对锌生物利用率的影响

用改良的离子交换法测定了学龄前儿童膳食植酸的摄入量,并用植酸/锌摩尔比值及人体代谢平衡实验评价和观察植酸抑制锌吸收利用的程度。 膳食植酸平均摄入499mg/d,植酸/锌摩尔比值平均为6.66。当摄取植酸含量高的食物时,植酸/锌摩尔比值也仅达到10.6。而抑制锌吸收的临界比值范围为10～20。代谢平衡实验未观察到锌的生物利用率受到抑制。 因此,在我国目前的膳食条件下,锌缺乏与植酸关系不大。     

Basal Urinary Zinc/Creatinine Ratio as an Indicator of Dietary Zinc Intake in Healthy Adult Women

Objective: To study, in healthy women, the correlation between the basal urinary zinc/creatinine ratio and dietary zinc intake.

Subjects: A group of 36 healthy female University students was evaluated. Mean age and body weight were, respectively, 25.6±3.3 years and 54.4±7.0 kg.

Methods: Basal urine was collected; Zn was determined by AAS and Creatinine (Creat) by the Jaffe method. A nutritional survey of seven days was recorded. Mean daily dietary intake of energy (DE) and zinc (DZn) were calculated according to the INCAP and English or German Food Composition Tables, respectively.

Results: Mean dietary daily intake were as follows (±SD): Energy (kcal): 1606±570; zinc (mg): 9.1±3.8; basal urine Zn/Creat ratio: 0.41±0.24. Individual values of the Zn/Creat ratio correlated with dietary Zn (r=0.481, p=0.0339); data grouped according to ranges of dietary Zn fit the following equation: Zn/Creat=0.160±0.034 DZn (mg/day); (r=0.870, p=0.00497).

Conclusions: These results showed that the basal urinary Zn/Creat ratio could be a useful indicator of dietary Zn intake in healthy adult women.     

邯郸市居民膳食摄入及膳食结构状况分析

目的了解邯郸市居民膳食摄入及膳食结构状况,为指导当地居民合理膳食,提高营养水平和促进健康提供科学依据。方法采用多阶段分层与人口成比例的整群随机抽样方法,以家庭为单位进行入户调查,利用3d24h膳食回顾和3d全家称重数据,用Excel建立数据库,用SPSS17.0统计软件进行数据分析。结果邯郸市居民膳食摄入以谷类为主,平均标准人日谷类食物摄入量440.9g,水果摄入量34.9g,奶及其制品摄入量52.6g,食用油、盐平均摄入量分别为43.2和11.7g。每标准人日摄入能量为8369.2kJ,蛋白质标准人日摄入量为60.9g;脂肪为85.5g,膳食纤维为11.4g。谷类食物提供的能量占总能量的47.8%,来源于脂肪提供的能量比例为37.9%。结论邯郸市居民膳食摄入以谷类为主,蔬菜和水果摄入明显不足,油、盐摄入相对较高,脂肪摄入高于全国水平,脂肪供能比超出建议范围,膳食结构不合理。相关部门应加强宣传与干预,倡导正确的平衡膳食理念。     

Relationship between Dietary Magnesium Intake and Metabolic Syndrome

Metabolic syndrome (MetS) is increasingly prevalent, and the relationship between dietary magnesium and MetS remains controversial. Therefore, we aimed to explore the association and dose-response relationship between dietary magnesium intake and MetS and its single component. The sample was adults aged 18 years and above who participated in at least two follow-up surveys in 2009, 2015 and 2018. Food consumption data were collected from three consecutive 24-h dietary recalls. The multivariate Cox proportional risk regression model and restricted cubic spline (RCS) model were used to analyze the association and dose-response relationship between dietary magnesium intake and MetS and its components. In our study, 6104 subjects were included, with a total follow-up of 37,173.36 person-years, and the incidence was 33.16%. Cox regression analysis showed that the multivariable-adjusted Hazard Ratio (HR) for MetS comparing the highest to the lowest quintile of dietary magnesium intake was 0.84 (95% confidence intervals [CI] = 0.71–0.99). Central obesity, elevated TG, elevated blood pressure and elevated blood glucose were reduced by 18%, 41%, 20% and 42%, respectively. The risk of decreased HDL-C was reduced by 23% in the third quintile of dietary magnesium intake, with a slightly increased risk in the highest group. RCS analysis showed that the overall and non-linear associations between dietary magnesium and MetS and its components were statistically significant, the risk of them decreased significantly when magnesium intake was lower than 280 mg/day, and then the curve leveled off or slightly increased.     

The Relationship between Zinc Intake and Serum/Plasma Zinc Concentration in Children: A Systematic Review and Dose-Response Meta-Analysis

Recommendations for zinc intake during childhood vary widely across Europe. The EURRECA project attempts to consolidate the basis for the definition of micronutrient requirements, taking into account relationships among intake, status and health outcomes, in order to harmonise these recommendations. Data on zinc intake and biomarkers of zinc status reported in randomised controlled trials (RCTs) can provide estimates of dose-response relationships which may be used for underpinning zinc reference values. This systematic review included all RCTs of apparently healthy children aged 1–17 years published by February 2010 which provided data on zinc intake and biomarkers of zinc status. An intake-status regression coefficient () was calculated for each individual study and calculated the overall pooled and SE () using random effects meta-analysis on a double log scale. The pooled dose-response relationship between zinc intake and zinc status indicated that a doubling of the zinc intake increased the serum/plasma zinc status by 9%. This evidence can be utilised, together with currently used balance studies and repletion/depletion studies, when setting zinc recommendations as a basis for nutrition policies.     

饲料不同锌营养水平对大鼠锌,铁,铜分布的影响

随摄入锌水平增加，毛、肾和胫骨中锌含量显著增加，毛、肝、睾丸和胫骨中铁含量显著减少，肝、肾中铜含量显著减少，毛中铜含量增加，铁的吸收与存留率相应减少，但无统计学意义。机体锦缺乏时．毛铁为评价机体铁营养状况较好的指标，而毛铜则很难反映机体铜的营养状况。     

Zinc Intake and Its Dietary Sources: Results of the 2007 Australian National Children's Nutrition and Physical Activity Survey

The current Australian Nutrient Reference Values (NRV) use different Estimated Average Requirements (EAR) for zinc for adolescent boys and girls compared to the previous recommendations. The adequacy of zinc intakes of 2-16 years old children (n = 4834) was examined in the 2007 Australian National Children's Nutrition and Physical Activity Survey. Zinc intakes were estimated from two 24-h recalls and compared with age- and gender-specific NRV. Food sources of zinc were assessed and compared with those of the 1995 National Nutrition Survey. The mean (SD) zinc intake was 10.2 (3.0) mg/day for all children. Nearly all children met the EAR for zinc except for 14-16 years old boys (29% did not meet EAR). Children (2-3 years) were at highest risk of excessive zinc intakes with 79% exceeding the Upper Level of Intake. Meat and poultry; milk products; and cereals and cereal products contributed 68% of total zinc intake. The contribution of cereals to total zinc intake has increased significantly since 1995, due to the greater market-availability of zinc-fortified breakfast cereals. We conclude that sub-groups of Australian children are at-risk of inadequate (boys 14-16 years) or excessive (children 2-3 years) zinc intakes, and monitoring of zinc status is required.     

某高校学生的膳食及营养状况调查

目的了解高校学生的膳食及营养状况,寻找主要存在的营养问题,以便制定干预措施。方法采用随机整群抽样的方法,抽取某高校20～23岁的165名学生;利用调查表对其膳食情况进行为期5d的记录。结果该人群异常体质的人占33.3%,且以体质偏轻为主。男、女大学生体质状况偏轻者分别占12.5%、33.1%。男、女大学生能量摄入均不足,分别达到RNI的66.8%和89.6%。男生膳食摄入蛋白质、脂肪略低于参考摄入量,碳水化合物摄入合理。女生脂肪、碳水化合物略低于参考摄入量,但蛋白质略高于RNI标准。结论大学生营养状况较差,膳食结构不合理。在高校开展有针对性的膳食营养健康教育十分必要。建议大学生适当调整膳食结构、提高营养水平、增强自身身体素质。     

缺锌儿童膳食营养素摄入水平的分析

对１４０名３～６岁缺锌儿童的营养调查表明：除维生素Ａ和铁外，其它多种营养素摄入偏低，锌与优质蛋白质摄入不足。临床体格检查与实验室检查发现，这些儿童血浆锌含量低下（６５８．２±７９．３ｍｇ／Ｌ），有食欲不振、厌食等表现。血清白蛋白水平正常，没有脱发、皮肤损害等体症，经补锌治疗后血浆锌显著升高，提示这些儿童为边缘性锌缺乏。     

恩施高硒区居民膳食硒摄入量监测报告

目的:通过比对恩施高硒区及其他地区居民膳食硒摄入量、血硒水平,了解不同时期恩施高硒区居民膳食硒摄入量。方法:对20世纪60年代、80年代及2012年的膳食硒摄入量、全血硒水平及癌症患病情况进行比对。结论:恩施高硒区居民每日膳食硒摄入量、血硒水平已经趋于正常;高硒区的癌症患者数量明显少于低硒区,适量硒摄入对癌症有一定的预防作用。     

口服补钙对铁、锌代谢影响的临床研究

观察口服补钙对铁、锌代谢的影响.方法给以相同饮的幼儿园儿童口服补钙每日130mg,连续2个月.观察其血常规、血清铁、锌的变化.结果实验组与对照组相比,补钙儿童血清铁降低;红细胞休积分布宽度增加;血红蛋白、红细胞平均血红蛋白及血清锌无明显变化.结论口服补钙可能影响饮食铁的吸收,致循环铁减少,并影响红细胞生成缺铁;而常规剂量补钙2个月对锌代谢无明显影响.