Speciation and bioavailability of iron in plant foods

缺铁是一个严重的公共健康问题，影响着全球约20亿人。如果不加以治疗，缺铁会导致缺铁性贫血(IDA)，在英国，IDA估计影响240万成年人、50万学龄前儿童和多达180万学龄儿童。我们饮食中的大部分铁存在于植物性食物中。然而，植物来源的铁的吸收变化很大，从0-15%不等，这是因为饮食中存在其他可以促进铁吸收的成分(例如维生素C)或抑制铁吸收的成分(例如植酸盐)。然而，人们对植物食物中不同形式的铁以及不同种类的铁如何被人体吸收知之甚少。此外，关于植物性食物的加工和消化对铁吸收的影响的数据也有限。我们在拟议项目中的目标是识别和表征选定的植物食物(例如小麦、豌豆和西兰花)中不同形式的铁，这些食物可能是英国饮食中良好的铁来源，并被认为含有不同的铁物种。我们将使用食品原料，但也会使用经过模拟消化的熟食和加工食品。我们聚集了一支拥有广泛专业知识的多学科团队，包括：(I)最先进的分析技术，将用于表征不同的铁形态，包括在植物组织和植物细胞中的分布；(Ii)将在英国国家同步加速器设施使用的全食品成像技术，以识别与高铁浓度相关的食品结构(Iii)高分辨率显微镜，光谱学和蛋白质组学，将被用来全面描述这些结构，并提供关于食物中结合铁的蛋白质的信息(Iv)使用人体细胞进行分析，这将被用来研究不同形式的铁在模拟消化之前和之后被人体吸收的可用性。这项研究将提供有关植物性食物中存在的铁的主要形式以及它们被人体吸收的情况的基本信息。从长远来看，有关铁结合蛋白的信息将有助于作物育种计划和选择天然富含铁的品种。从该项目获得的知识将有助于开发具有更高铁生物利用率的植物食品和加工食品产品，以及设计更接近于饮食中自然存在的铁的形式的有效和安全的替代铁食品增强剂。最后，我们的数据将更好地为政策制定者、监管机构、营养咨询团体和健康专业人士提供有关改善英国人口铁状况的战略。

Iron deficiency is a serious public health problem which affects around 2 billion people worldwide. When left untreated iron deficiency leads to iron deficiency anaemia (IDA) and in the UK IDA affects an estimated 2.4 million adults, 500 thousand pre-school children and up to 1.8 million school-age children. The majority of the iron in our diet is present in plant foods. However, absorption of plant-derived iron is very variable, ranging from 0-15%, due to the presence of other components in the diet that can enhance iron absorption (for example vitamin C) or inhibit iron absorption (for example phytate). However, very little is known about the different forms of iron in plant foods and how different species are absorbed by the body. Also, thrre are limited data on the effects of processing and digestion of plant foods on iron absorption. Our aim in the proposed project is to identify and characterise the different forms of iron in selected plant foods (for example wheat, peas and broccoli) that are potentially good sources of iron in the UK diet and are believed to contain different iron species. We will use the raw food materials but also cooked and processed foods following simulated digestion. We have gathered together a multidisciplinary team with a range of expertise, including: (i) state-of-the-art analytical techniques that will be used to characterize the different iron forms, including the distribution in plant tissues and plant cells (ii) whole food imaging techniques that will be used at the UK's national synchrotron facility to identify structures within foods associated with high iron concentrations (iii) high resolution microscopy, spectroscopy and proteomics that will be used to fully characterise these structures and to provide information on proteins in the foods that bind iron (iv) assays using human cells that will be used to study the availability of the different forms of iron for absorption by the body before and after simulated digestion. This research will provide essential information on the major forms of iron present in plant-based foods and how well they are absorbed by the body. Information on iron-binding proteins will be useful in the long-term to aid crop breeding programmes and select for varieties that are naturally rich in iron. Knowledge gained from this project will enable the development of plant foods and processed food products with higher iron bioavailability and the design of efficacious and safe alternative iron food fortificants that more closely represent the forms of iron naturally present in the diet. Finally, our data will better inform policy makers, regulatory authorities, nutrition consultative groups and health professionals on strategies for improving the iron status of the UK population.