膳食叶酸参考摄入量研究进展

叶酸是一种水溶性维生素,作为一碳单位的载体,参与核苷酸合成、DNA甲基化反应,对于人体细胞生长、分化、修复至关重要,并具有预防神经管缺陷的作用。随着对于叶酸与出生缺陷、心血管疾病、肿瘤以及神经退行性疾病的关系的研究逐步深入,叶酸已成为一种备受关注的微量营养素。叶酸缺乏可导致成人和儿童巨幼红细胞贫血,增加孕妇发生先兆子痫、胎盘早剥、贫血的风险,可导致孕妇自发性流产。孕早期叶酸缺乏可引起胎儿神经管缺陷。中国从2010年开始向育龄妇女推荐叶酸补充剂,以预防神经管缺陷。本文针对叶酸膳食参考摄入量的制定及研究进展进行梳理回顾,旨在为中国居民膳食营养素参考摄入量叶酸的修订提供参考。[营养学报,2023,45(4):326-330]     

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。     

膳食核黄素参考摄入量国内外研究进展

<正>核黄素又称维生素B2,为人体所必需的一种水溶性维生素,作为辅酶在氧化还原反应、能量代谢等方面发挥着重要作用^[1]。核黄素缺乏会引起唇炎、舌炎、口角炎、口腔溃疡、阴囊皮炎、角膜血管增生等症状。     

肝硬化患者如何掌握蛋白质摄入量

辽宁大连读者刘某来信说：今年52岁，确诊患肝硬化已十年。最近去医院化验发现白蛋白明显降低，为33克/升。自以为多食用蛋白质食物可以提高血清白蛋白含量。谁知却出现了肝昏迷前兆，到医院输入复方氨基酸才恢复。请问专家，像我这种情况，如何食用蛋白质食物，     

膳食营养素参考摄入量的制定原理和应用方法

随着时代变迁和经济发展,食物结构和膳食营养观念不断变化着,人们对膳食营养要求越来越高.本文结合我国人民的膳食营养素供给情况和应用,对膳食营养素摄入量的制定原理与应用方法进行了阐述和探讨.     

国内外维生素K研究现状及膳食参考摄入量修订进展

<正>维生素K(vitamin K,VK)是人体必需的营养素,最早是由丹麦科学家Henrik Dam提取分离出维生素K₁并命名为凝血维生素^[1],之后美国科学家Edward Doisy从动物源食物中提取了维生素K₂。此后,VK凝血功能之外的多种健康效应逐渐被发现,如促进骨形成、防治骨质疏松症、降低心血管疾病风险、抑制癌细胞增殖等。但目前尚无公认的评价指标和判定界值,因此难以评估VK的营养状况和需要量。当前,国际组织和各国均以健康人群的膳食摄入量来制定VK的适宜摄入量(adequate intake,AI)。     

我国三个人群蛋白质摄入量,血、尿氨基酸水平与血压的关系

本文分析了膳食蛋白质摄入的质与量,空腹血清及八小时夜尿中游离氨基酸含量与血压的关系。结果表明,膳食动物蛋白质/总蛋白质,蛋白质/钠摄入量的比值,血清及尿牛磺酸,赖氨酸等和血压呈显著负相关;丙氨酸等和血压显著正相关;血清氨基酸和膳食蛋白质/钠比值显著正相关;尿牛磺酸,赖氨酸,门冬酰胺等和蛋白质摄入量,钠摄入量及排泄量显著正相关。提示富含牛磺酸,赖氨酸等的优质蛋白质可能预防高血压。     

修订《中国居民膳食参考摄入量》参考资料 (八)澳新膳食营养素参考摄入量北大核心CSCD

澳大利亚和新西兰政府向公众提供营养指导已超过75年,包括告知“推荐膳食摄入量”（RDIs）或“供给量”,即避免缺乏状态的平均每日营养素需要量。指导以“膳食指南”及与文化相关的膳食模式表述,不仅达到预防缺乏的目的,而且能减少慢性病风险。     

氮平衡指数(NBI)评价氨基酸强化大米蛋白质的营养价值

本研究用氟平衡指数对氨基酸强化大米的效果进行了探讨。作者在用断乳鼠以PER、NPR、PRE和NPU等指标衡量氨基酸强化大米效果的基础上,进一步用多水平蛋白质的氮平衡指数确证其作用。研究包括成年鼠和断乳鼠二个系列实验。结果表明;同时用0.5％L-赖氨酸和0.3％DL-苏氨酸强化大米均接近全蛋粉的效价,单独用0.3％或0.5％L-赖氨酸强化大米在断乳鼠也有提高蛋白效价的作用。用含有相应强化比例的氨基酸的脱脂豆粉补充大米,对氮平衡的作用也与氨基酸强化作用近似。     

锰的适宜摄入量研究进展

锰是人体可能必需的微量元素,2013版《中国居民膳食营养素参考摄入量》(dietary reference intakes, DIRs)依据中国居民营养与健康状况监测和锰的代谢实验对锰的适宜摄入量(adequate intake, AI)进行了修订。随着国内外营养科学工作的发展及我国居民膳食模式和生活方式的变迁,我国开始对DIRs进行新一轮的修订。现对国内外的锰参考摄入量的研究进展以及不同国家/国际组织锰参考摄入量的修订概况进行介绍。     

Estimating the impact of mandatory folic acid fortification on the folic acid intake of Australian women of childbearing age

Objective : The primary aim of this study was to estimate the impact of mandatory folic acid (FA) fortification of bread‐making flour on the FA intake of Australian women of childbearing age (16–44 years). The secondary objective was to investigate the relationship between estimated FA intake and socio‐economic status (SES) and age. Method : Dietary modelling was used to estimate FA intake under four mandatory fortification scenarios – no supplement use, supplement use unrelated to FA intake, supplement use only among the highest consumers of bread, and increased supplement use. Data were obtained from the 1995 National Nutrition Survey for food intake patterns, the 2007 Victorian Population Health Survey for FA supplement use, and a marketplace survey. Results : It is estimated that the National Health and Medical Research Council (NHMRC) recommendation for an additional 400 mg/day FA will be achieved by a minimum of 3.9, 25.4, 21.7 and 30% of the target population under scenarios 1–4, respectively. The FA upper level of intake is exceeded by a maximum of 0.1, 1.7, 6.1 and 4.1% of the target population for scenarios 1–4, respectively. Conclusions : Mandatory FA fortification is not sufficient for the NHMRC recommendations for minimum and maximum intakes to be met by all of the target population under a number of plausible behaviour scenarios. Implications : Targeted nutrition education campaigns are needed for SES and age sub‐groups and research of this nature should be extended to other population groups. Monitoring and evaluation of this policy will be important to ensure appropriate FA intake.     

肺心病患者营养摄入与血浆游离氨基酸代谢变化的探讨

对39例肺心病患者的热能-蛋白质摄入量,血清前白蛋白(PA),转铁蛋白(Tr)和血浆游离氨基酸(FAA)进行测定.结果表明:肺心病组能量.蛋白质摄入量明显低于对照组,血浆PA、Tr浓度明显低于对照组差异显著(P<0.01);肺心组血浆中支链氨基酸(BCAA)、苏AA、色AA、蛋AA、甘AA、丙AA、酪AA、精AA、明显低于对照组,仅胱AA浓度高于对照组差异显著(P<0.05);食物蛋白质摄入量与血浆PA浓度呈显著相关(r=0.833,P<0.01),血浆PA与血浆色AA浓度呈显著相关(r=0.835,P<0.01).结果提示:肺心病患者均存在有营养不良状态,血浆PA、Tr浓度降低和血浆FAA谱的改变均与热能蛋白质摄入量减少有关.     

Impact of nutrient intake timing on the metabolic response to exercise

Effects of nutrient intake timing and exercise on carbohydrate (e.g. insulin sensitivity), protein (muscle protein synthesis), and fat (circulating triacylglycerols) metabolism are reviewed in this paper. Altered nutrient intake timing relative to exercise can modulate the metabolic response, which is relevant for individuals seeking to use exercise to enhance health.     

利用多水平方差成份模型探讨个人动物蛋白摄入量的影响因素

以中国８省人口、经济与营养健康调查的资料为例，利用多水平模型探讨了在平衡个人因素后省、县、家庭三个水平上的因素对动物蛋白摄入比例的影响。发现家庭因素如平均收入、饮食习惯、对饮食营养的认识程度等是影响动物蛋白摄入的较重要因素；此外，还发现不同省、不同县动物蛋白的摄入存在差异，揭示出摄入动物蛋白比例的增长还可能与各地区饮食文化和种植特点有关。从而可以为改善我国营养结构提供一些较为客观的依据。对于不同模型的比较认为多水平模型可以有效地用于当前许多大型卫生调查中具有层次结构的数据的分析，克服普通回归模型的不足     

现有维生素D的膳食参考摄入量急需提高

维生素D补充可能在降低许多慢性疾病风险中发挥作用。为了快速、显著降低维生素D不足引起疾病的发生率,通过维生素D强化食品或维生素D补充剂增加其摄入量是一个简单、低成本的方法,但目前可耐受最高摄人量和推荐摄入量已经过时。笔者敦促有关方面,作为高度优先事项重新评估维生索D的膳食参考摄入量。     

Patterns of food and nutrient intake in a suburb of Dublin with chronically high unemployment

The diet-history (7 typical recent days) method was used to determine patterns of food and nutrient intake in 50 families, randomly selected from the electoral register of a socially disadvantaged Dublin suburb. Some 66% of income was from unearned social security or other payments. Financial assistance was sought from money lenders by 11 of the 50 families. There was little evidence to suggest that nutrient intakes among males or among children were inadequate. Women, because of a low energy intake and a below average intake of meat, had low intakes of iron (8.1 ±2.3 mg/d). Women also had low intakes of fibre and vitamin C (14 ± 5 and 45 ± 18 mg/d, respectively). These low intakes of fibre and vitamin C among women relative to the RDAs were characterized by low intakes of fruits, vegetables, cereals and pulses. Single mothers (n –10) had the lowest intakes of iron, vitamin C or fibre although their incomes and food expenditures were average. The children of single-parent families had identical intakes of nutrients to all other children. The estimated cost of the average energy intake of adolescent children (e.g. boys 11–18 years, IRE15-10/week) well exceeded their social security payments.     

Comparison of caloric and nutrient intake of adults during week and week-end days

Three-day food records in 174 women and 185 men were used to compare caloric and nutrient intake of week and week-end days. Both women and men were found to consume significantly more energy and a higher level of alcohol during the week-end days than during the week days. In women, a significant decrease in calcium intake was observed during the week-end days in the 36–40 and the 41–45 age groups, respectively. In general, the significant increase in energy intake did not correspond to a significant increase in other nutrients.     

Effect of a breakfast program on the nutrient intake of black children

The effect of a free breakfast program was evaluated by comparing the 24‐hr, dietary intake of 252 black children who attended one school offering a breakfast program with the intake of 303 black children at a nearby school where breakfast was not served. Although the mean intake of the children in both schools was close to, or greater than, the RDA for all the nutrients under study, approximately 48 percent of the children reported diets that provided less than two‐thirds of the RDA for one or more nutrients. The children attending the breakfast school consumed significantly more of their total daily nutrient intake before 10 a.m. than the children in the control school. These differences were more pronounced among the children with poor diets. Also, a significantly greater number of children from the control school reported that they had nothing to eat prior to 10 a.m. These observations indicate that the breakfast program had a beneficial effect.