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Efficacy of Non-heme Iron Fortified Diets: A Review
Critical Reviews In Food Science and Nutrition
Abstract
Iron deficiency anemia (IDA) is prevailing around the globe at variable extent. To combat this phenomenon various strategies are popular. One effective strategy is food fortification. A number of reviews are available to discuss the bioavailability of food fortificants exclusively or in special dietary arrangements with specific food vehicles to access their performance in order to overcome the iron deficiency problem. However, little consideration is given to the efficacy studies of these dietary settings. This review is meant for discussing the efficacy of non-heme iron fortified diets.
... Une des principales a été d'essayer de supplémenter des produits alimentaires avec du fer. Une étude a fait le bilan de différentes approches [9] et a conclu dans un premier temps que l'accès à des essais cliniques était un frein important à la validation des différentes pistes envisagées. D'autre part, les auteurs de cette étude ont pointé une problématique importante disant qu'ajouter du fer au sein d'une matrice alimentaire complexe, même si elle contient des composants capables d'augmenter l'absorption du fer (fibres), n'améliorent pas forcément la biodisponibilité du fer. ...
... Ce type d'association correspondrait au "egg-box" décrit dans la littérature. On remarque également un minimum de potentiel plus large et beaucoup moins profond à des distances plus grandes (4,5 -5,5 Å) qui correspond à un type d'interaction de type SSIP (Solvent-Shared Ion Pair) 9 . Lorsque l'on regarde la barrière d'énergie libre entre les minimums correspondant aux association CIP et le minimum correspondant 9. Ce type d'interaction correspond au partage de la couche d'hydratation de deux éléments qui, ici, sont le carboxylate et le cation divalent. ...
... On remarque également un minimum de potentiel plus large et beaucoup moins profond à des distances plus grandes (4,5 -5,5 Å) qui correspond à un type d'interaction de type SSIP (Solvent-Shared Ion Pair) 9 . Lorsque l'on regarde la barrière d'énergie libre entre les minimums correspondant aux association CIP et le minimum correspondant 9. Ce type d'interaction correspond au partage de la couche d'hydratation de deux éléments qui, ici, sont le carboxylate et le cation divalent. ...
Ce travail de thèse décrit la formulation d'hydrogels de polygalacturonate (polyGal) réticulés par les cations Fe2+, ainsi que leur caractérisation expérimentale depuis les échelles moléculaires jusqu'aux échelles macroscopiques, en utilisant notamment la spectroscopie d'absorption X (EXAFS), la diffusion de neutrons aux petits angles (DNPA) ainsi que des mesures de rhéologie. Nous avons élaboré un protocole de gélification robuste permettant d'obtenir des gels cylindriques reproductibles qui présentent des gradients de concentrations contrôlés depuis leur partie basale jusqu'à leur partie apicale. Le rapport R = [Fe]/[Gal] a une valeur constante de 0,25 tout au long du gel, ce qui prouve que les cations Fe2+ s'associent avec 4 unités galacturonate. La confrontation des résultats d’EXAFS et de dynamique moléculaire a démontré que ces associations se font via le modèle ''egg-box''. Les mécanismes de réticulation qui contrôlent la structure du réseau formée par les chaînes aux échelles locales sont donc les mêmes dans l'ensemble du gel, ce qui est confirmé par les mesures de DNPA. La formation des gradients de concentration macroscopiques provient des mécanismes de diffusion des cations à travers le gel lors de sa formation. Ces gradients de concentration contrôlent les propriétés mécaniques des gels. En outre, nous avons prouvé que le mode d'association "egg-box" permettait la protection des ions Fe2+ contre l'oxydation, ce qui confère à ces hydrogels un potentiel applicatif pour soigner l'anémie car ils pourraient permettre la vectorisation du fer sous cette forme réduite biodisponible jusqu’à l’intestin.Nous avons étendu notre étude à la formulation d'hydrogels avec d'autres cations (Ca2+ et Zn2+). Ces hydrogels présentent des propriétés macroscopiques proches de celles des hydrogels Fe2+-polyGal car les mécanismes de diffusion des cations régissant la formation des gradients macroscopiques lors de la formation des gels sont similaires. Les hydrogels présentent cependant des structures locales différentes car les modes d'associations locaux varient d"un cation à l’autre. L’ensemble de ces résultats nous a permis de proposer un mécanisme généralisé permettant de décrire les mécanismes de formation d"hydrogels de polygalacturonate pour les cations divalents, et ainsi de moduler finement leur structure sur plusieurs échelles. Ces hydrogels pourraient donc être des outils de choix pour la vectorisation de molécules actives et le contrôle de leur relargage.
... Many mechanisms for iron uptake that are found in lower organisms also occur in humans, and in the human body, iron is contained in the form of heme proteins such as hemoglobin and myoglobin, or non-heme complexes such as transferrin and ferritin. More than 60% of the body's iron is incorporated in hemoglobin, about quarter is present in the form of a readily mobilizable iron store, and 15% is bound in myoglobin and in enzymes that participate in metabolic and cellular functions [107]. ...
... A simple model of copper absorption by enterocytes. Adapted from Ref.[107]. ...
In total, twenty elements appear to be essential for the correct functioning of the human body, half of which are metals and half are non-metals. Among those metals that are currently considered to be essential for normal biological functioning are four main group elements, sodium (Na), potassium (K), magnesium (Mg), and calcium (Ca), and six d-block transition metal elements, manganese (Mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn) and molybdenum (Mo). Cells have developed various metallo-regulatory mechanisms for maintaining a necessary homeostasis of metal-ions for diverse cellular processes, most importantly in the central nervous system. Since redox active transition metals (for example Fe and Cu) may participate in electron transfer reactions, their homeostasis must be carefully controlled. The catalytic behaviour of redox metals which have escaped control, e.g. via the Fenton reaction, results in the formation of reactive hydroxyl radicals, which may cause damage to DNA, proteins and membranes. Transition metals are integral parts of the active centres of numerous enzymes (e.Dg. Cu,Zn-SOD, Mn-SOD, Catalase) which catalyze chemical reactions at physiologically compatible rates. Either a deficiency, or an excess of essential metals may result in various disease states arising in an organism. Some typical ailments that are characterized by a disturbed homeostasis of redox active metals include neurological disorders (Alzheimer's, Parkinson's and Huntington's disorders), mental health problems, cardiovascular diseases, cancer, and diabetes. To comprehend more deeply the mechanisms by which essential metals, acting either alone or in combination, and/or through their interaction with non-essential metals (e.g. chromium) function in biological systems will require the application of a broader, more interdisciplinary approach than has mainly been used so far. It is clear that a stronger cooperation between bioinorganic chemists and biophysicists - who have already achieved great success in understanding the structure and role of metalloenzymes in living systems - with biologists, will access new avenues of research in the systems biology of metal ions. With this in mind, the present paper reviews selected chemical and biological aspects of metal ions and their possible interactions in living systems under normal and pathological conditions.
... The ability of hemoglobin hydrolysate to promote absorption of non-heme iron may be attributed to the special amino acids and peptides produced from hemoglobin hydrolysis. The poor absorption efficiency of non-heme iron in vivo is due to its low solubility [36] . The carboxyl, hydroxyl and amino groups of amino acids and peptides increase the solubility of non-heme iron in combination with it [18,37] . ...
... The ability of hemoglobin hydrolysate to promote absorption of non-heme iron may be attributed to the special amino acids and peptides produced from hemoglobin hydrolysis. The poor absorption efficiency of non-heme iron in vivo is due to its low solubility [36]. The carboxyl, hydroxyl and amino groups of amino acids and peptides increase the solubility of non-heme iron in combination with it [18,37]. ...
Hemoglobin hydrolysate is derived from the enzymatic degradation of hemoglobin. This work aimed to evaluate whether hemoglobin hydrolysate promotes the absorption of non-heme iron and the safety of absorbed iron in mice by analyzing the iron binding content, iron circulation, and liver homeostasis. We found that hemoglobin hydrolysate promoted the absorption of non-heme iron with high efficiency in duodenum by spontaneously binding non-heme iron during digestion, and increased hepatic iron content by up-regulating divalent metal transporter 1, zinc transporter 14, but hepatic iron content only increased at 3 weeks. Duodenal iron entered the blood through ferroportin without restriction at 3 weeks, and excessive iron entered the liver and then affected the hepatocyte membranes permeability and lipid synthesis through oxidative stress. With the prolongation of dietary intervention, the up-regulated hepcidin acted on the ferroportin to restrict excess iron from entering the blood, and then the hepatic homeostasis recovered. In addition, hemoglobin hydrolysate enhanced the hepatic antioxidant capacity. Taken together, hemoglobin hydrolysate has a strong ability to promote the absorption of non-heme iron in vivo, and the absorbed iron is relatively safe due to the regulation of hepcidin.
... tion/topic s/ida/en/; Lyons et al. 2005a;Alina et al. 2019). This has resulted in overall poor health including problems like anaemia, increased morbidity and mortality rates, and low worker productivity among those affected with deficiency of micronutrients (Hotz and Brown 2004;Welch and Graham 2004;Bouis 2007;Cakmak 2008;Salim-Ur-Rehman et al. 2010). In developing countries, where major fraction of the population relies on cereal grain as their staple food, malnutrition due to deficiency for micronutrients has been particularly high among children; the phenomenon has been described as 'hidden hunger' (Stein and Qaim 2007;Harding et al. 2018;Godecke et al. 2018). ...
Key message
Knowledge of genetic variation, genetics, physiology/molecular basis and breeding (including biotechnological approaches) for biofortification and bioavailability for Zn, Fe and Se will help in developing nutritionally improved wheat.
Abstract
Biofortification of wheat cultivars for micronutrients is a priority research area for wheat geneticists and breeders. It is known that during breeding of wheat cultivars for productivity and quality, a loss of grain micronutrient contents occurred, leading to decline in nutritional quality of wheat grain. Keeping this in view, major efforts have been made during the last two decades for achieving biofortification and bioavailability of wheat grain for micronutrients including Zn, Fe and Se. The studies conducted so far included evaluation of gene pools for contents of not only grain micronutrients as above, but also for phytic acid (PA) or phytate and phytase, so that, while breeding for the micronutrients, bioavailability is also improved. For this purpose, QTL interval mapping and GWAS were carried out to identify QTLs/genes and associated markers that were subsequently used for marker-assisted selection (MAS) during breeding for biofortification. Studies have also been conducted to understand the physiology and molecular basis of biofortification, which also allowed identification of genes for uptake, transport and storage of micronutrients. Transgenics using transgenes have also been produced. The breeding efforts led to the development of at least a dozen cultivars with improved contents of grain micronutrients, although land area occupied by these biofortified cultivars is still marginal. In this review, the available information on different aspects of biofortification and bioavailability of micronutrients including Zn, Fe and Se in wheat has been reviewed for the benefit of those, who plan to start work or already conducting research in this area.
... Micronutrient deficiency is of increasing global concern with over 30 and 60% of the world population estimated to suffer from the deficiency of Zn and Fe, respectively (White and Broadly, 2009). This result in overall poor heath, anaemia, increased morbidity and mortality rates, and reduced worker productivity (Welch and Graham, 2004;Bouis, 2007;Peleg et al., 2008;Rehman et al., 2010). According to WHO (2011), 43% of the world children, 38% of pregnant women, 29% of nonpregnant women and 29% of all women of reproductive age are anaemic. ...
Fe and Zn deficiency are widespread worldwide. As wheat is the primary food for the majority of the world people, producing wheat grains with high mineral content can ameliorate the problem of mineral hunger. However, the genetic variation available for breeders is limited. The aim of this study was to assess the genetic variation in grain Fe and Zn contents in 47 synthetic hexaploid wheats and to identify marker loci associated with Fe and Zn contents. We measured the grain Fe and Zn contents using inductively coupled plasma atomic emission spectroscopy and performed genotyping using SSR markers. The results showed considerable genetic variation for these minerals. We identified three lines with high Fe and Zn contents and six quantitative trait loci of which three were associated with Fe content and the other three with Zn content. The minerals showed positive phenotypic and genotypic correlation and high heritability (>60%). The ratio of the σ 2 g to the σ 2 g×e was ≥1 for the two mineral contents indicating that breeding for increasing mineral content within the synthetic lines is possible. The synthetic wheat lines identified in this study are valuable genetic resources, and can be utilized for breeding wheat cultivars with high mineral content.
... It has been suggested that communities whose major dietary intake is dependent on plant-derived foods, should consider iron fortification [10]. The World Health Organization (WHO) recommends ferrous sulfate, ferrous fumarate and sodium iron EDTA (NaFeEDTA) for the fortification of wheat and maize [11]. ...
... For example, the presence of ascorbate promotes digestive passage of non-heme iron in the reduced form as soluble ferrous iron, versus otherwise insoluble ferric hydroxides. Conversely, a number of competitive ligands for non-heme iron such as: bran, polyphenols, egg yolk, soy calcium and phytic acid may compromise luminal absorption (Salim Ur et al. 2010). ...
Lactoferrin (Lf), present in colostrum and milk is a member of the transferrin family of iron-binding glyco-proteins, with stronger binding capacity to ferric iron than hemoglobin, myoglobin or transferrin. Unlike hemoglobin and myoglobin, iron-bound Lf is reasonably stable to gastric and duodenal digestive conditions. Unlike ferrous iron, ferric iron is not directly reactive with oxygen supporting the capacity of Lf capture of heme iron to suppress reactive oxygen species (ROS) production. We therefore hypothesized that bovine Lf could capture and thereby terminate the cycle of ROS production by heme iron. The transfer of heme iron from either intact or digested forms of hemoglobin and myoglobin and from intact ferritin was demonstrated by in vitro methods, monitoring Fe-saturation status of Lf by changes in absorptivity at 465 nm. The results are discussed in the context of new proposed opportunities for orally administered Lf to regulate oxidative damage associated with heme iron. In addition to potentially suppressing oxidative heme-iron-mediated tissue damage in the lumen, Lf is expected to also reverse the overload of ferritin-bound iron, that accompanies chronic inflammation and aging. These new proposed uses of Lf are additional to known host defense functions that include anti-microbial, anti-viral properties, immune and cancer cell growth regulation. The findings and interpretations presented require clinical substantiation and may support important additional protective and therapeutic uses for Lf in the future.
... The food industry, in particular, has the potential to play a key role in improving the utilisation of iron from foods that are currently sold and using scientific and technological advances to enhance this even further. More specifically, the food industry may consider improving the bio-availability of iron from non-haem foods, or fortifying these foods with additional iron (Salim et al., 2010). As demonstrated in Table 2, in the United Kingdom, bread may be a good vehicle for the delivery of additional iron as this food product is consumed regularly and in predictable amounts. ...
Iron deficiency is one of the most common nutritional deficiencies worldwide, in both developing and developed regions. Although the aetiology of iron deficiency and resultant anaemia may be multifaceted, inadequate iron intakes, poor iron absorption and disease status may all be underlying causes. Whilst nutrition and supplement interventions may go some way towards improving iron status in ‘at-risk’ populations, their efficacy can be questioned. New approaches, including food-based strategies, may be an alternative means of improving the iron status and health of the public sectors. Economically, food-based approaches may also be more cost-effective than iron supplements. This paper aims to discuss how the food industry may play an important role in improving the iron status of public sectors, helping to prevent iron deficiency and need for tablet-based iron supplements.
... The food industry, in particular, has the potential to play a key role in improving the utilisation of iron from foods that are currently sold and using scientific and technological advances to enhance this even further. More specifically, the food industry may consider improving the bio-availability of iron from non-haem foods, or fortifying these foods with additional iron (Salim et al., 2010). As demonstrated in Table 2, in the United Kingdom, bread may be a good vehicle for the delivery of additional iron as this food product is consumed regularly and in predictable amounts. ...
Habitual iron intakes during pregnancy are typically lower than dietary guidelines, a risk for iron deficiency. The aim of this study was to determine whether regular consumption of bread naturally rich in iron could help women to achieve dietary targets. Thirty-three primiparous mothers were randomized to eat 3-4 slices of iron-rich or control bread daily for 6 weeks. Two 24-h-prompted (multiple-pass) dietary recalls were completed, and validated algorithms were used to determine the amount of 'available iron' from the diet. Regular consumption of iron-rich bread helped pregnant women to achieve UK dietary recommendations; the quantity of bread consumed by the participants contributed 27% versus 9% UK Reference Nutrient Intake (RNI) (14.8 mg/d) in the intervention versus the control group. Levels of total 'available iron' were similar in both groups and correlated positively with total dietary iron (r = 0.78, P = 0.0001), vitamin C (r = 0.43, P = 0.017) and non-haem iron (r = 0.77, P = 0.0001). Findings from this study show that iron-rich staple foods can help women reach dietary targets for iron. This is an area of great potential that could be of particular benefit to low-income/ethnically diverse population groups who have some of the lowest iron intakes. Further research using fortified staple foods containing higher levels of iron is now warranted to establish physiological benefits.
Both iron metabolism and ferroptosis (an iron-dependent form of programmed cell death) have been connected to the development and progression of many currently incurable non-communicable diseases, including Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, Huntington’s disease, metabolic dysfunction-associated steatohepatitis, heart failure, and both treatment-relapsed and refractory cancers, such as pancreatic ductal adenocarcinoma and triple-negative breast cancer. Thus, understanding the relationship between iron and these diseases can pave the way for the development of novel therapeutic strategies. Here, we summarize the latest evidence supporting the pathological roles of dysregulated iron metabolism and ferroptosis in a wide range of preclinical animal models of these currently incurable non-communicable diseases. We also summarize the feasibility of targeting iron metabolism and ferroptosis for the prevention and treatment of iron- and ferroptosis-related diseases that currently have limited treatment options. In addition, we provide our perspectives on the challenges and promises regarding the translational potential of targeting dysregulated iron metabolism and ferroptosis to treat diseases, highlighting the future roadmap for developing iron- and ferroptosis-targeted therapeutics.
Reducing lead (Pb) exposure via oral ingestion of contaminated soils is highly relevant for child health. Elevating dietary micronutrient iron (Fe) intake can reduce Pb oral bioavailability while being beneficial for child nutritional health. However, the practical performance of various Fe compounds was not assessed. Here, based on mouse bioassays, ten Fe compounds applied to diets (100–800 mg Fe kg–1) reduced Pb oral relative bioavailability (RBA) in two soils variedly depending on Fe forms. EDTA-FeNa was most efficient, which reduced Pb-RBA in a soil from 79.5 ± 14.7% to 23.1 ± 2.72% (71% lower) at 100 mg Fe kg–1 in diet, more effective than other 9 compounds at equivalent or higher doses (3.6–68% lower). When EDTA-FeNa, ferrous gluconate, ferric citrate, and ferrous bisglycinate were supplemented, Fe-Pb co-precipitation was not observed in the intestinal tract. EDTA-FeNa, ferrous gluconate, ferric citrate, and ferrous sulfate suppressed duodenal divalent metal transporter 1 (DMT1)mRNA relative expression similarly (27–68% lower). In comparison, among ten compounds, EDTA-FeNa elevated Fe concentrations in mouse liver, kidney, and blood (1.50–2.69-fold higher) most efficiently, suggesting the most efficient Fe absorption that competed with Pb. In addition, EDTA was unique from other organic ligands, ingestion of which caused 12.0-fold higher Pb urinary excretion, decreasing Pb concentrations in mouse liver, kidney, and blood by 68–88%. The two processes (Fe-Pb absorption competition and Pb urinary excretion with EDTA) interacted synergistically, leading to the lowest Pb absorption with EDTA-FeNa. The results provide evidence of a better inhibition of Pb absorption by EDTA-FeNa, highlighting that EDTA-FeNa may be the most appropriate supplement for intervention on human Pb exposure. Future researches are needed to assess the effectiveness of EDTA-FeNa for intervention on human Pb exposure.
Iron deficiency is a global nutritional problem, and adding iron salts directly to food will have certain side effects on the human body. Therefore, there is growing interest in food-grade iron delivery systems. This review provides an overview of iron delivery systems, with emphasis on the controlled release of iron during gastrointestinal digestion, as well as the enhancement of iron absorption and bioavailability. Iron-bearing proteins are easily degraded by digestive enzymes and absorbed through receptor-mediated endocytosis. Instead, protein aggregates are slowly degraded in the stomach, which delays iron release and serves as a potential iron supplement. Amino acids, peptides and polysaccharides can bind iron through iron binding sites, but the formed compounds are prone to dissociation in the stomach. Moreover, peptides and polysaccharides can deliver iron by mediating the formation of ferric oxyhydroxide which is absorbed through endocytosis or bivalent transporter 1. In addition, liposomes are unstable during gastric digestion and iron is released in large quantities. Complexes formed by polysaccharides and proteins, and microcapsules formed by polysaccharides can delay the release of iron in the gastric environment and prolong iron release in the intestinal environment. This review is conducive to the development of iron functional ingredients and dietary supplements.
Iron is a vital micronutrient required for growth and development at all stages of human life. Its deficiency is the primary cause of anemia that poses a significant global health problem and challenge for developing countries. Various risks are involved during iron deficiency anemia (IDA), such as premature delivery, low birth weight, etc. Further, it affects children's cognitive functioning, delays motor development, hampers physical performance and quality of life. It also speeds up the morbidity and mortality rate among women. The major reasons accountable are elevated iron demand in diet, socio-economic status, and disease condition. Various strategies have been adopted to reduce the IDA occurrence, such as iron supplementation, iron fortificants salts, agronomic practices, dietary diversification, biofortification, disease control measures, and nutritional education. Usually, the staple food groups for fortification are considered, but the selection of food fortificants and their combination must be safe for the consumers and not alter the finished product's stability and acceptability. Genetically modified breeding practices also increase the micronutrient levels of cereal crops. Therefore, multiple strategies could be relied on to combat IDA.
About one-third of the world population is suffering from iron deficiency. Delivery of iron through diet is a practical, economical, and sustainable approach. Clinical studies have shown that the consumption of iron-fortified foods is one of the most effective methods for the prevention of iron deficiency. However, supplementing iron through diet can cause undesirable side-effects. Thus, it is essential to develop new iron-rich ingredients, iron-fortified products with high bioavailability, better stability, and lower cost. It is also essential to develop newer processing technologies for more effective fortification. This review compared the iron supplementation strategies used to treat the highly iron-deficient population and the general public. We also reviewed the efficacy of functional (iron-rich) ingredients that can be incorporated into food materials to produce iron-fortified foods. The most commonly available foods, such as cereals, bakery products, dairy products, beverages, and condiments are still the best vehicles for iron fortification and delivery.
Scope of review
The manuscript aims at providing a comprehensive review of the latest publications that cover three aspects: administration routes for iron supplementation, iron-rich ingredients used for iron supplementation, and iron-fortified foods.
The aim of the study, carried out in 2012-2014, was to evaluate the content of iron and zinc in the grain of 15 hybrid lines of Aegilops kotschyi Boiss. and Ae. variabilis Eig. with Triticum aestivum L. and their parent forms. The content of micronutrients was analysed in grain samples from the plants with the highest 1,000 grain weight. The Fe and Zn content was determined by the ASA method. The study showed that the grain of the hybrid lines had a higher iron and zinc content (mean results from three years: 42.3 mg Fe kg⁻¹ DW and 43.5 mg Zn kg⁻¹ DW) than that of the parent wheat components (35.2 mg Fe kg⁻¹ DW and 33.3 mg Zn kg⁻¹ DW). The highest content of iron and zinc was found in the seeds of the wild parent species Ae. kotschyi Boiss (59.7 mg Fe kg⁻¹ DW and 54.0 mg Zn kg⁻¹ DW) and Ae. variabilis Eig. (61.9 mg Fe kg⁻¹ DW and 49.1 mg Zn kg⁻¹ DW). Among the hybrids of Ae. variabilis Eig. with T. aestivum L., the line Ae. variabilis Eig. × Rusałka stood out, with its grain containing on average 56.3 mg Fe kg⁻¹ DW and 57.2 mg Zn kg⁻¹ DW. Among the Ae. kotschyi Boiss × T. aestivum L. lines, the highest iron and zinc content was noted in the grain of Ae. kotschyi Boiss × Rusałka (51.9 mg Fe kg⁻¹ DW and 51.3 mg Zn kg⁻¹ DW), (Ae. kotschyi Boiss. × Rusałka) × Korweta (45.1 mg Fe kg⁻¹ DW and 44.4 mg Zn kg), and [(Ae. kotschyi Boiss. × Rusałka) × Begra] × Piko (42.0 mg Fe kg⁻¹ DW and 49.2 mg Zn kg⁻¹ DW). The average iron content in the grain of the common wheat cultivars ranged from 32.3 mg kg⁻¹ DW (cv. Piko) to 37.5 mg kg⁻¹ DW (cv. Begra), and the zinc content ranged from 29.6 mg kg⁻¹ DW (cv. Muza) to 36.7 mg kg⁻¹ DW (cv. Turnia). © 2018, Polish Society Magnesium Research. All rights reserved.
Micronutrient deficiency (Iron and Zinc) is the major problem worldwide mostly in the developing countries with high
dependence on staple foods. Biofortification of staple cereal and tuber crops has been considered and taken up as the
most effective, feasible and economic approach for alleviating micronutrient deficiency. The present study was the
initiative towards biofortification of wheat where the previous work of wide hybridization between HD2687 and Aegilops
longissima accession 3506 and subsequent backcrossing with Triticum aestivum cultivar WL711 has been continued. In
this study the alien chromosome introgression, chromosomal stability of BC1F6 and BC2F4 wheat-Ae. longissima derivatives
has been investigated for their potential as germplasm for future breeding and biofortification program through morphological,
cytological and biochemical analysis. We found that the selected derivatives showed stable 42, 44 and 46 chromosomes
for most of the plants where single plant reported for each 41, 43 and 45 chromosomes with 19-22 bivalents and few
trivalent. The GISH analysis of derivative 79-1-4-8-1-2-2 revealed introgression of two univalent Sl chromosomes.
Finally four derivatives were selected from BC1F6 (79-1-4-8-10-2-2, 79-1-4-8-10-2-5, 79-2-4-4-1-1-3 and 79-2-4-4-1-1-
5) and three from BC2F4 (HD2687/L3506//WL711-3///WL711-1-2-7-1, HD2687/L3506//WL711-3///WL711-1-2-7-3,
HD2687/L3506//WL711-3///WL711-1-2-7-5) as stable biofortified lines for future breeding to alleviate hidden hunger.
Bananas and plantains (Musa sp.) are major staple foods in many developing countries of the world. Although bananas are rich in carbohydrate, fiber, protein, fat, and vitamins A, C, and B6 they are largely deficient of iron (Fe), iodine, and zinc (Zn). A small increase in the micronutrient content of bananas could play a major role in combating disorders that are due to deficiency of mineral micronutrients such as Fe and Zn. The objective of this study was to determine the Fe and Zn content of 47 banana genotypes from a germplasm collection in Uganda using atomic absorption spectropho-tometry. The Fe and Zn content showed wide variability and highly significant differences (P < 0.001) within and among the different banana categories selected for this study. The highest average Fe content (1.42 mg/100 g) was found in ‘Saba’ (ABB) while the least Fe content (0.06 mg/100 g) was found in ‘Kikundi’ (AAA). The highest average Zn content (1.21 mg/100 g) among the analyzed accessions was found in ‘Kivuvu’ (ABB) while Zn was not detectable in both ‘Kabucuragye’ (AAA) and ‘Grand Naine’ (AAA). Considering these figures, there is a greater than 20-fold variation in the Fe and Zn levels of the banana genotypes used this study suggesting that genetic improvement of genotypes for enhanced micronutrient levels may be achieved by breeding. © 2016, American Society for Horticultural Science. All rights reserved.
INTRODUCCIÓN La anemia constituye el principal problema nutricional
en los niños preescolares cubanos. Tal situación estimuló la
realización de intervenciones de salud por parte de las autoridades
sanitarias cubanas con el propósito de prevenir y controlar la enfermedad.
En 2008 se estableció una estrategia nacional integral que
proporcionó atención particular a las provincias orientales del país,
por constituir la región con los más grandes desafíos en los determinantes
sociales de salud.
OBJETIVO Determinar la prevalencia de anemia en los niños de 6
a 59 meses en las cinco provincias orientales de Cuba en tres años
diferentes dentro de una década, así como estudiar la asociación de
la anemia con los factores epidemiológicos y nutricionales, para evaluar
el impacto del Plan Integral Cubano para la Prevención y el Control
de la Anemia por Deficiencia de Hierro en Cuba.
MÉTODOS Se realizaron estudios de corte transversal en muestras
representativas de la población de los niños con 6 a 59 meses, residentes
en las provincias orientales del país, en los años 2005, 2008
y 2011. Se midió el nivel de hemoglobina para diagnosticar la anemia
(hemoglobina menor de 110 g/L) y los resultados se relacionaron con
variables independientes tales como la edad, el sexo, el área de residencia
(urbana o rural), la asistencia a círculos infantiles [guarderías
para niños entre 1 y 5 años de edad, pertenecientes al Sistema Nacional
de Educación de Cuba —Eds.], el peso al nacer, la historia de
lactancia materna, así como la anemia materna durante el embarazo.
Se calcularon las frecuencias de distribución, las comparaciones se
evaluaron mediante la prueba de 2 y los Odds Ratio (OR) con intervalos
de confianza (IC) del 95%.
RESULTADOS La prevalencia de anemia en la región estudiada disminuyó
de 31.8% en 2005 a 26% en 2011; en la mayoría de los casos
era leve (hemoglobina = 100-109 g/L). La prevalencia fue superior en
los niños de 6 a 23 meses comparado con los que tenían de 24 a 59
meses. No se encontró diferencia significativa en la prevalencia de anemia
entre niños y niñas. La prevalencia fue superior en las áreas rurales
comparadas con las áreas urbanas en 2005 (p = 0.026) y en 2011
(p = 0.012). La asistencia a círculos infantiles constituyó un factor protector
en los tres años estudiados. El bajo peso al nacer solo estuvo
asociado con la anemia en 2011 (OR 1.74, IC 1.04-2.92). La prevalencia
de la lactancia materna de forma exclusiva durante los seis primeros
meses de vida se incrementó durante el período de estudio y
la anemia se asoció con la no utilización de lactancia materna exclusiva
en 2005 (OR 1.57, IC 1.05-2.34). La anemia materna al inicio y
durante el embarazo fue un factor de riesgo significativo tanto en 2005
(OR 1.98, IC 1.27-3.10) como en 2011 (OR 1.43, IC 1.05-1.94).
CONCLUSIONES Aunque la prevalencia de anemia disminuyó paulatinamente
durante el período del estudio, la enfermedad continúa siendo
un problema de salud pública en Cuba, por lo que se deben mantener
y fortalecer las medidas para su prevención y su control, tales como
realizar intervenciones de salud sobre las mujeres en edad reproductiva,
la alimentación exclusiva por lactancia materna durante los primeros seis
meses de edad, estimular el cumplimiento de las recomendaciones de
las normas cubanas para la alimentación complementaria de los niños
hasta los dos años de edad, así como continuar la evaluación y la investigación
de las causas de la anemia en los niños en edad preescolar.
The bioavailability of ingested components is an extremely important area of food and pharmaceutical research. The main issue is to determine which fraction of ingested nutrients or food pollutants can be truly used by the body and exert its healthy or deleterious effects. In this sense, knowledge of bioavailability is essential to estimate the quantity of a mineral that must be supplied to satisfy the requirements, since low intake from diet and deficiencies (with negative consequences for health) are found worldwide, and also to evaluate the toxicological risk of contaminant minerals. Physiological and dietetic factors, as well as food processing, can have an impact on mineral bioavailability. Accordingly, this chapter reviews the bioavailability of minerals of nutritional interest (Ca, Fe, Zn and Se) and with toxicological risk (As, Hg, Cd and Pb).
Deficiencies of iron (Fe) and zinc (Zn) in afflict over three billion people worldwide, and deficiencies of these minerals in soil also limit crop production in one-third (Fe) and nearly half (Zn) of the world's total cereal growing area. Screening genetic resources for improving wheat grain Fe and Zn contents and efficiency can contribute to both human health and crop production. We evaluated 47 wheat-Aegilops disomic addition lines derived from 6 Aegilops species to identify the chromosomes carrying genes for high grain Fe and Zn concentrations. Addition lines with chromosomes 1S(1) and 2S(1) of Ae. longissima, 1S(S) and 2S(S) of Ae. searsii, 2U and 6U of Ae. umbellulata, B of Ae. caudata, 4S(v) of Ae. peregrina, and 5 M-g of Ae. geniculata showed increased grain Fe or Zn concentration of between 50% and 248% compared with the recipient cultivar, Chinese Spring. Most of alien chromosomes addition lines with significantly higher grain Fe and/or Zn concentrations belonged to the U and S genotypes and homoeologous groups 1 and 2 chromosomes. These lines could be used for the precise introgression of genes into elite wheat cultivars to improve wheat micronutrient concentrations.
Introduction:
Anemia is the main nutritional problem in Cuban preschool children, prompting several interventions to prevent and control it. An enhanced national strategy was established in 2008, and particular attention paid to the eastern provinces, the region with greatest challenges in social determinants of health.
Objective:
Determine anemia prevalence in children aged 6-59 months in Cuba's five eastern provinces in three separate years within a decade, as well as association of anemia with epidemiological and nutritional factors, to assess impact of Cuba's Comprehensive Plan for Prevention and Control of Iron-Deficiency Anemia in Cuba.
Methods:
Cross-sectional studies of children aged 6-59 months (completed) were conducted in 2005, 2008 and 2011. Hemoglobin levels were measured to diagnose anemia (hemoglobin <110 g/L) and data were collected on independent variables such as age, sex, area of residence (urban or rural), daycare center enrollment, birth weight, breastfeeding history, and maternal anemia during pregnancy. Frequency distributions were created and comparisons tested with the chi square, and odds ratios calculated with 95% confidence intervals.
Results:
Anemia prevalence in the region fell from 31.8% in 2005 to 26% in 2011; most of cases were mild (hemoglobin: 100-109 g/L). Prevalence was higher in children aged 6-23 months than in those aged 24-59 months throughout. No significant differences were found in anemia prevalence between boys and girls. Prevalence was higher in rural than in urban areas in 2005 (p = 0.026) and 2011 (p = 0.012). Daycare enrollment emerged as a protective factor in all three years. Low birth weight was associated with anemia only in 2011 (OR 1.74, CI 1.04-2.92). Prevalence of exclusive breastfeeding for six months increased over the study period; lack of breastfeeding was found to be associated with anemia in 2005 (OR 1.57, CI 1.05-2.34). Maternal anemia at onset of and during pregnancy was a significant risk factor in 2005 (OR 1.98, CI 1.27-3.10) and 2011 (OR 1.43, CI 1.05-1.94).
Conclusions:
Although anemia prevalence steadily decreased over the study period, it continues to be a public health problem in Cuba and anemia prevention and control measures should be maintained and strengthened: interventions for women of childbearing age, fostering exclusive breastfeeding of infants through their sixth month, and encouraging compliance with recommendations on complementary feeding per Cuba's nutritional guidelines for children aged <2 years. Further evaluation is needed to identify the causes of anemia in the population of preschool children.
A nutritional study was conducted on 150 female college students aged 18 to 23 at the Punjab Agricultural University, Ludhiana, India, to evaluate the effectiveness of "MSU Nutriguide: Asian Indian Foods," a computer programme for assessing nutrient intakes and total energy expenditure (TEE) of the Indian population. A non-significant difference between analysed and calculated values for energy, protein, iron, and ascorbic acid revealed that the intake of the nutrients calculated with the MSU Nutriguide was a correct assessment in most of the subjects. TEE estimation by MSU Nutriguide gives values based on age, height, weight, and four levels of physical activity (sleeping and light, moderate, and heavy activity), whereas prediction equations are based on the body weight of each subject and a single level of activity. Therefore, MSU Nutriguide can be efficiently used to assess the TEE of people in India.
Objective: The impact of the cassava flour fortified with iron amino acid chelate was evaluated in 80 pre-scholars of a Philanthropic Unit of Manaus, state of Amazonas, randomly distributed in four groups of 20 children each, for a period of 120 days. Methods: Cassava flour was used without fortification (group zero) or fortified with 1, 2 and 3mg of Fe/day, corresponding respectively to 5, 10 and 15g of flour/day, which were given to the children at lunch time on weekdays. The equivalent amount was previously distributed to their families for flour intake also during the weekends. In the beginning and at the end of the experiment the children's nutritional status was evaluated, being adopted the cutoff point <-2 Z-scores as a discriminating limit between eutrophymalnutrition, in agreement with the World Health Organization criteria, as well as being established as a cutoff point for the occurrence of iron deficiency anemia a hemoglobin rate of less than 11g/dL. Results At the end of this study, children recovered from chronic malnutrition, and a significant increase (p <5%) of the hemoglobin rates, independently of iron concentration, from 11.4±0.9g/dL to 12.2±0.8g/dL, was observed in all individuals. The formerly anemic children who received cassava flour fortified with 2mg of Feday were fully recovered at the end of the research, demonstrating a good performance of this group in relation to the others. Conclusion: A double-blind study is suggested for the consolidation of the recommendation of cassava flour fortified with iron in the prevention of iron deficiency anemia in pre-scholars of the Amazon region.
A systematic review was conducted to identify studies assessing the effect of food fortification with iron on childhood anemia. The MEDLINE, LILACS, and PubMed databases and WHO and PAHO sites were searched with no time limita- tion, including articles published in Portuguese, English, or Spanish, using the following key words and their combination: food fortification, iron, effectiveness, efficacy, anemia, flour, staple foods, interventions, and children. Of 21 stud- ies reviewed, only one failed to report a positive, favorable effect of iron fortification, indicating the possibility of publication bias. The studies showed important methodological limitations. The two studies with the best methodological scores showed opposite results, highlighting the need for larger trials with better planning to ex- plore this hypothesis.
The effect of packaging materials on the physicochemical and rheological characteristics of iron-fortified wholemeal flour (WMF) during storage was determined. WMF was fortified with three fortificants, namely ferrous sulfate (30 ppm), ferrous sulfate + ethylenediamine tetraacetic acid (EDTA) (20 + 20 ppm) and elemental iron (60 ppm). Each flour was also fortified with 1.5 ppm folic acid. Moisture, flour acidity and peroxide value increased during storage, while protein and fat contents decreased. Highest conversion of Fe2+ into Fe(3+)was observed in flour fortified with ferrous sulfate (2.72%), followed by that fortified with ferrous sulfate + EDTA (1.49%) and elemental iron (1.06%). Water absorption and dough viscosity of iron-fortified flours increased during storage. The flour containing ferrous sulfate was most acceptable regarding sensory characteristics, followed by samples containing ferrous sulfate + EDTA. Fortified flours were more stable during storage than unfortified. Addition of EDTA increased the stability of flours and fortificants. The fortified flours stored in polypropylene bags proved more stable than those stored in the tin boxes.
The effect of Fe fortification on the absorption of Zn was studied by radioisotopic labelling of single meals, followed by measurements of whole-body retention of 65Zn at 14 d after intake. Healthy adult volunteers participated in the study. Weaning cereal, wheat bread and infant formula, foods that are all frequently Fe-fortified, were evaluated in the study. The amounts of Fe added as FeSO4 were similar to the levels in commercial products in Europe and the USA, and were 200 or 500 mg Fe/kg (weaning cereal), 65 mg Fe/kg (white wheat flour) and 12 mg Fe/l (infant formula). For comparison, Zn absorption was measured in the same subjects, from identical test meals containing no added Fe. No statistically significant differences were found when Zn absorption from the Fe-fortified test meals was compared with that from non-Fe-fortified test meals. Fractional Zn-absorption values from Fe-fortified v. non-fortified meals were 31.1 (SD 11.9) v. 30.7 (SD 7.0)% (weaning cereal; 200 mg Fe/kg), 37.7 (SD 16.6) v. 30.2 (SD 9.9)% (weaning cereal; 500 mg Fe/kg), 36.5 (SD 14.4) v. 38.2 (SD 18.1)% (bread; 65 mg Fe/kg flour) and 41.6 (SD 8.1) v. 38.9 (SD 14.5)% (infant formula; 12 mg Fe/l). The addition of Fe to foods at the currently used fortification levels was thus not associated with impaired absorption of Zn and the consumption of these Fe-fortified foods would not be expected to have a negative effect on Zn nutrition.
OBJETIVO: Avaliou-se o impacto da farinha de mandioca fortificada com ferro aminoácido quelato em 80 pré-escolares de uma Unidade Filantrópica de Manaus, AM, distribuídos aleatoriamente em quatro grupos de 20 crianças cada, por um período de 120 dias. MÉTODOS: Foram utilizadas farinha de mandioca sem fortificação (Grupo zero) e fortificada com 1, 2 e 3mg de Fe/dia, correspondendo a quantias diárias de 5, 10 e 15g de farinha, respectivamente, as quais foram distribuídas no horário do almoço, sendo ainda entregue às famílias a quantidade destinada ao consumo do final de semana. O estado nutricional das crianças foi avaliado no início e ao final do experimento, adotando-se como limite discriminatório entre eutrofia/desnutrição o ponto de corte
Observou-se a eficácia da fortificação do leite fluido com 3 mg de ferro aminoácido quelato no combate à carência de ferro em crianças menores de quatro anos. Foram acompanhadas 269 crianças que receberam, durante 12 meses, um litro de leite fortificado por dia, e que foram avaliadas a cada 6 meses de acompanhamento. Antes de se iniciar a intervenção, a anemia estava presente em 62,3% das crianças. Após 6 meses, este percentual reduziu-se a 41,8% e, ao final de um ano, a 26,4%. As maiores reduções foram detectadas nas faixas etárias de 12 a 23 meses e em menores de um ano. Das crianças que apresentavam hemoglobinas iniciais inferiores a 9,5 g/dl, 59,3% recuperaram-se da anemia ao final de um ano de acompanhamento. Naquelas com hemoglobinas iniciais entre 9,5 e 10,9 g/dl, o percentual de recuperação da anemia foi de 66,7%. Encontrou-se, ainda, melhores evoluções hematológicas em crianças que ingeriam quantidades superiores a 750 ml/dia de leite fortificado, pertencentes a famílias que não dividiam o suplemento recebido com outros membros e naquelas com apenas uma criança com menos de 5 anos no núcleo familiar. Concluiu-se pela viabilidade e eficácia da fortificação do leite fluido como medida de intervenção no combate à carência de ferro em pré-escolares.
Foi avaliado o impacto do uso do leite em pó integral fortificado com 9 mg de ferro e 65 mg de vitamina C para cada 100 g de pó, sobre os níveis de hemoglobina de crianças menores de 2 anos, em 107 crianças de creches municipais e 228 de uma Unidade Básica de Saúde (UBS), por um período de 6 meses. Antes de se iniciar a intervenção, 66,4% das crianças das creches e 72,8% da UBS apresentavam níveis de hemoglobina inferiores a 11,0 g/dl. Ao final dos 6 meses de uso do leite fortificado, esses percentuais reduziram-se para 20,6% nas creches e 18,0% na UBS. A média da hemoglobina, antes de se iniciar o experimento, foi de 10,3 g/dl nas creches e 10,5 g/dl na UBS. Decorridos 6 meses esses valores subiram para 11,6 g/dl nas duas populações estudadas. Em relação à condição nutricional, avaliada pelo critério de Gomez, verificou-se que, nas creches, 57% das crianças acompanhadas apresentaram melhoria na sua condição nutricional, 41,1% ficaram inalteradas e apenas 1,9% pioraram. Na UBS, 11,4% apresentaram melhora, 70,6% ficaram inalteradas e 18% pioraram, o que mostrou uma diferença de resposta quanto à recuperação da condição nutricional, quando o leite enriquecido foi utilizado em ambiente aberto e fechado. Concluiu-se que a utilização de alimentos fortificados apresenta-se como excelente alternativa para o controle da carência de ferro em populações de crianças menores de 2 anos.
1. The feasibility of improving iron nutrition by fortifying cane sugar with Fe and ascorbic acid was studied. 2. It was found to be possible to add a number of Fe salts together with ascorbic acid to sugar without affecting its appearance or storage properties. 3. The absorption of Fe from fortified sugar eaten with maize-meal porridge or made into jam or biscuits was measured in ninety-four volunteer multiparous Indian women using the 59-Fe erythrocyte utlization method. 4. The absorption of Fe from sugar fortified with ascorbic acid and ferrous sulphate and eaten with maize-meal porridge was increased about twofold in the ratio, ascorbic acid:Fe was 10:1 by weight. If the ratio was increased to 20:2, Fe absorption was increased a further threefold. 5. Sugar fortified with soluble Fe salts, including FeSO4.7H2O, discoloured both tea and coffee; sugar fortified with ferric orthophosphate did not have this effect. 6. Fe from FePO4.H2O was poorly absorbed when added with sugar to maize-meal porridge, and also when added with adequate quantities of ascorbic acid. This form of Fe was absorbed much less well than was the intrinsic Fe present in the maize. 7. When sugar fortified with FePO4.H2O and ascorbic acid was added to maize-meal porridge before cooling or was made into jam there was a several-fold increase in the amount of Fe absorbed.
The effect of reducing the phytate in soy-protein isolates on nonheme-iron absorption was examined in 32 human subjects. Iron absorption was measured by using an extrinsic radioiron label in liquid-formula meals containing hydrolyzed corn starch, corn oil, and either egg white or one of a series of soy-protein isolates with different phytate contents. Iron absorption increased four- to fivefold when phytic acid was reduced from its native amount of 4.9-8.4 to less than 0.01 mg/g of isolate. Even relatively small quantities of residual phytate were strongly inhibitory and phytic acid had to be reduced to less than 0.3 mg/g of isolate (corresponding to less than 10 mg phytic acid/meal) before a meaningful increase in iron absorption was observed. However, even after removal of virtually all the phytic acid, iron absorption from the soy-protein meal was still only half that of the egg white control. It is concluded that phytic acid is a major inhibitory factor of iron absorption in soy-protein isolates but that other factors contribute to the poor bioavailability of iron from these products.
Iron absorption from 3.38 mg 58Fe was measured in riboflavin-deficient Gambian men with haemoglobin (Hb) less than 11.5 g/dl before and after oral riboflavin therapy, and the results compared with a group not receiving riboflavin. Riboflavin status (as determined by erythrocyte glutathione reductase activation coefficient) and Hb increased in teh riboflavin-supplemented but not placebo group. Plasma ferritin levels were low and did not change in either group. There was very wide variation in percentage iron absorption between individuals and also within single individuals on two separate occasions but no measurable change with riboflavin supplementation. The results of the study indicate that the efficiency of iron utilization is impaired in riboflavin deficiency, but that iron absorption is unaffected.
Iron absorption and daily loss of Fe were measured in riboflavin-deficient (B2-) Norwegian hooded rats and controls (B2+). Animals were fed on a test meal extrinsically labelled with 59Fe and whole-body radioactivity measured for 15 d. Riboflavin deficiency led to a reduction in the percentage of the 59Fe dose absorbed and an increased rate of 59Fe loss. All post-absorption 59Fe loss could be accounted for by faecal 59Fe, confirming that the loss was gastrointestinal. Fe concentrations and 59Fe as a percentage of retained whole-body 59Fe were higher in the small intestine of riboflavin-deficient animals than their controls, 14 d after the test meal. A separate experiment demonstrated that riboflavin deficiency was associated with a significant proliferative response of the duodenal crypts of the small intestine. These observations may explain the enhanced Fe loss in riboflavin deficiency.
A targeted, double-blind controlled iron fortification trial using Fe(111)-EDTA in masala (curry powder) was directed towards an Fe-deficient Indian population for 2 y. The Fe status of the fortified group improved more than that of control subjects. Improvement reached significance over control subjects for females in hemoglobin (p = 0.0005), ferritin (p = 0.0002), and body Fe stores (p = 0.001) and for males in ferritin (p = 0.04). The prevalence of Fe-deficiency anemia (IDA) decreased from 22 to 5% in fortified females. Premenopausal women, multipara women, and women with prolonged menstruation or initial IDA benefitted most from fortification. The mean increase in body Fe stores in females with initial IDA was 9.0 +/- 1.3 mmol, representing an increased absorption of 12 mumol/d. Fortified subjects with normal Fe status did not accumulate excessive body Fe and there was no alteration in serum Zn concentrations. Targeted fortification is a safe and effective means of combatting Fe deficiency.
The effect of the two major bovine milk protein fractions on the dialyzability of iron in vitro under simulated gastrointestinal conditions and on the absorption of Fe by humans was studied. Liquid-formula meals were prepared from hydrolyzed maize starch, corn oil, and either spray-dried egg white or a milk-protein product. In meals containing egg white, 3.32% of the Fe was dialyzable. The substitution of casein and whey protein products reduced the dialyzable fraction to 0.19-0.56% and 0.86-1.60%, respectively. Percentage Fe absorption was also reduced by the substitution of casein or whey protein for egg white. Mean absorption values fell from 6.67 to 3.65% and 2.53 to 0.98%, respectively. When the intact milk-protein products were replaced by enzyme- or acid-hydrolyzed preparations, the dialyzable fraction increased markedly and in proportion to the extent of hydrolysis. A similar but much smaller effect on absorption was observed. These studies suggest that bovine casein and whey proteins are responsible at least in part for the poor bioavailability of the Fe in some infant formulas.
The level of assimilation of dietary iron is believed to have an important influence on iron status. To examine the effect of enhancing the availability of dietary iron on iron balance, 17 adult volunteer subjects were given 2 g of ascorbic acid daily with meals for 16 weeks. Serum ferritin levels before and after the study averaged 46 and 43 micrograms/L, respectively, indicating a negligible effect on iron stores. When vitamin C supplementation was continued for an additional 20 months in five iron-replete and four iron-deficient subjects, serum ferritin determinations again failed to indicate any significant effect of the vitamin C on iron reserves. These findings were not explained by intestinal adaptation to the enhancing effect of the vitamin, because radioisotopic measurements of nonheme iron absorption showed no reduction in the enhancing effect of 1 g of ascorbic acid after four months of megadoses of vitamin C. It is concluded that altering the availability of nonheme dietary iron has little effect on iron status when the diet contains substantial amounts of meat.
The iron status of a population of 1564 subjects living in the northwestern United States was evaluated by measurements of transferrin saturation, red cell protoporphyrin, and serum ferritin. The frequency distribution of these parameters showed no distinct separation between normal and iron-deficient subjects. When only one of these three parameters was abnormal (transferrin saturation below 15%, red cell protoporphyrin above 100 mug/ml packed red blood cells, serum ferritin below 12 ng/ml), the prevalence of anemia was only slightly greater (10.9%) than in the entire sample (8.3%). The prevalence of anemia was increased to 28% in individuals with two or more abnormal parameters, and to 63% when all three parameters were abnormal. As defined by the presence of at least two abnormal parameters, the prevalence of iron deficiency in various populations separated on the basis of age and sex ranged from 3% in adolescent and adult males to 20% in menstruating women. It is concluded that the accuracy of detecting iron deficiency in population surveys can be substantially improved by employing a battery of laboratory measurements of the iron status.
The level of assimilation of dietary iron is believed to have an important influence on iron status. To examine the effect of enhancing the availability of dietary iron on iron balance, 17 adult volunteer subjects were given 2 g of ascorbic acid daily with meals for 16 weeks. Serum ferritin levels before and after the study averaged 46 and 43 micrograms/L, respectively, indicating a negligible effect on iron stores. When vitamin C supplementation was continued for an additional 20 months in five iron-replete and four iron-deficient subjects, serum ferritin determinations again failed to indicate any significant effect of the vitamin C on iron reserves. These findings were not explained by intestinal adaptation to the enhancing effect of the vitamin, because radioisotopic measurements of nonheme iron absorption showed no reduction in the enhancing effect of 1 g of ascorbic acid after four months of megadoses of vitamin C. It is concluded that altering the availability of nonheme dietary iron has little effect on iron status when the diet contains substantial amounts of meat.
Traditionally, the main strategies used to control micronutrient deficiencies have been food diversification, consumption of medicinal supplements, and food fortification. In Tanzania, we conducted efficacy trials using a dietary supplement as a fourth approach. These were randomized, double-blind, placebo-controlled efficacy trials conducted separately first in children and later in pregnant women. The dietary supplement was a powder used to prepare an orange-flavored beverage. In the school trial, children consumed 25 g per school day attended. In the pregnancy trial, women consumed the contents of two 25-g sachets per day with meals. This dietary supplement, unlike most medicinal supplements, provided 11 micronutrients, including iron and vitamin A, in physiologic amounts. In both trials we compared changes in subjects consuming either the fortified or the nonfortified supplement. Measures of iron and vitamin A status were similar in the groups at the baseline examination, but significantly different at follow-up, always in favor of the fortified groups. Children receiving the fortified supplement had significantly improved anthropometric measures when compared with controls. At four weeks postpartum, the breast milk of a supplemented group of women had significantly higher mean retinol content than did the milk of mothers consuming the nonfortified supplement. The advantages of using a fortified dietary supplement, compared with other approaches, include its ability to control several micronutrient deficiencies simultaneously; the use of physiologic amounts of nutrients, rather than megadoses that require medical supervision; and the likelihood of better compliance than with the use of pills because subjects liked the beverage used in these trials.
One cost-effective strategy for controlling iron deficiency is the fortification of staple foods or condiments with iron. We evaluated the effectiveness of fortifying fish sauce with NaFeEDTA for improving iron status in women of childbearing age in Vietnam in a double-blind intervention with randomization by village. All families in the selected villages were supplied with fish sauce that was either unfortified (Group C, 10 villages) or fortified with NaFeEDTA [9 mmol (500 mg) Fe/L, Group F, 11 villages] for 18 mo. The effect of fortification was assessed in the 576 women (n = 288/group) by measuring hemoglobin and serum ferritin (SF) at 6, 12, and 18 mo. Analysis of the group × time interaction using a repeated-measures test for each response demonstrated a significant effect of fortification on hemoglobin (P = 0.039) and log SF (P < 0.0001) in Group F with no significant changes in Group C. The prevalence of iron deficiency (SF < 12 μg/L) decreased from 22.3 to 4.0% and the prevalence of anemia (hemoglobin < 120 g/L) from 24.7 to 8.5% in Group F with no significant changes in Group C. NaFeEDTA fortification of fish sauce is an effective method for reducing the prevalence of iron deficiency in women in Vietnam.
1. The feasibility of improving iron nutrition by fortifying cane sugar with Fe and ascorbic acid was studied.
2. It was found to be possible to add a number of Fe salts together with ascorbic acid to sugar without affecting its appearance or storage properties.
3. The absorption of Fe from fortified sugar eaten with maize-meal porridge or made into jam or biscuits was measured in ninety-four volunteer multiparous Indian women using the ⁵⁹ Fe erythrocyte utilization method.
4. The absorption of Fe from sugar fortified with ascorbic acid and ferrous sulphate and eaten with maize-meal porridge was increased about twofold if the ratio, ascorbic acid: Fe was 10:1 by weight. If the ratio was increased to 20:1, Fe absorption was increased a further threefold.
5. Sugar fortified with soluble Fe salts, including FeSO 4 . 7H 2 O, discoloured both tea and coffee; sugar fortified with ferric orthophosphate did not have this effect.
6. Fe from FePO 4 . H 2 O was poorly absorbed when added with sugar to maize-meal porridge, and also when added with adequate quantities of ascorbic acid. This form of Fe was absorbed much less well than was the intrinsic Fe present in the maize.
7. When sugar fortified with FePO 4 .H 2 O and ascorbic acid was added to maize-meal porridge before cooking or was made into jam there was a several-fold increase in the amount of Fe absorbed.
The effects of different polyphenol-containing beverages on Fe absorption from a bread meal were estimated in adult human subjects from the erythrocyte incorporation of radio-Fe. The test beverages contained different polyphenol structures and were rich in either phenolic acids (chlorogenic acid in coffee), monomeric flavonoids (herb teas, camomile (Matricaria recutita L.), vervain (Verbena officinalis L.), lime flower (Tilia cordata Mill.), pennyroyal (Mentha pulegium L.) and peppermint (Mentha piperita L.), or complex polyphenol polymerization products (black tea and cocoa). All beverages were potent inhibitors of Fe absorption and reduced absorption in a dose-dependent fashion depending on the content of total polyphenols. Compared with a water control meal, beverages containing 20-50 mg total polyphenols/serving reduced Fe absorption from the bread meal by 50-70%, whereas beverages containing 100-400 mg total polyphenols/serving reduced Fe absorption by 60-90%. Inhibition by black tea was 79-94%, peppermint tea 84%, pennyroyal 73%, cocoa 71%, vervain 59%, lime flower 52% and camomile 47%. At an identical concentration of total polyphenols, black tea was more inhibitory than cocoa, and more inhibitory than herb teas camomile, vervain, lime flower and pennyroyal, but was of equal inhibition to peppermint tea. Adding milk to coffee and tea had little or no influence on their inhibitory nature. Our findings demonstrate that herb teas, as well as black tea, coffee and cocoa can be potent inhibitors of Fe absorption. This property should be considered when giving dietary advice in relation to Fe nutrition.
The relationship between high dietary iron intake, mutations of the HFE gene, and iron status, and their effects on human health are reviewed. Prolonged high dietary intakes of iron are unlikely to result in iron overload in the general population. Homozygotes for the C282Y mutation of the HFE gene have elevated body iron levels. Heterozygotes have normal iron stores but some may be at increased risk for cardiovascular disease. There is no convincing evidence that elevated iron status increases the risk of coronary heart disease or type 2 diabetes, but high iron intakes may increase the risk of colorectal cancer The dietary levels of iron associated with health risks in different HFE genotypes must be determined. (C) 2003 International Life Sciences Institute.
During the last decades efforts regarding dietary iron supply focused mostly on the prevention of deficiencies, especially during growth and pregnancy. Correspondingly, homeostatic mechanisms increase intestinal iron absorption in iron deficiency, but its downregulation at high intake levels seems insufficient to prevent accumulation of high iron stores at high intake. There is no regulated iron excretion in overload. Excess of pharmaceutical iron may cause toxicity and therapeutic doses may cause gastrointestinal side effects. Chronic iron excess, e.g. in primary and secondary hemochromatosis, may lead to hepatic fibrosis, diabetes mellitus and cardiac failure. Chronic intake of 50–100 mg Fe/day of highly bioavailable iron with home-brewed beer in sub-Saharan Africans lead to cirrhosis and diabetes. Applying a safety factor of 2 would lead to an upper safe level of 25–50 mg Fe/day for this endpoint of conventional iron toxicity. However, beyond this kind of damage iron is known to catalyze the generation of hydroxyl radicals from superoxide anions and to increase oxidative stress which, in turn, increases free iron concentration. This self-amplifying process may cause damage to lipid membranes and proteins, which relates radical generation and organ damage after ischemia-reperfusion events to available free iron in clinical and experimental settings. Correspondingly, epidemiological studies as well as observations in heterozygotes for hereditary hemochromatosis suggest that the risk of atherosclerosis and acute myocardial infarction is related to body iron stores, though there is conflicting epidemiological evidence as well. The most recent and best controlled studies, however, support the hypothesis that iron stores are related to cardiovascular risk. Iron-amplified oxidative stress may also increase DNA damage, oxidative activation of precancerogens and support tumor cell growth. This is supported by experimental, clinical and epidemiological observations. Due to these mechanisms high iron stores may present a health hazard. Though this has not been finally proven, available evidence strongly recommends not to increase iron intake beyond physiological requirements. To avoid iron deficiency symptoms, on the other hand, care must be taken to meet recommended daily intake.
Purpose: This study assesses the efficacy of an iron-fortified (15 mg Fe, as stabilized ferrous sulfate (SFE-171), per liter) fluid whole cow's milk (IFFWCM) for the treatment of mild iron deficiency in children. Previous studies in healthy adult volunteers showed a mean 10.2 +/- 4.7% iron absorption. Patients and Methods: Seventeen children (12 to 48 months old) with iron deficiency (serum iron (SI) <60 [mu]g/dl, transferrin saturation (TS) <15%, serum ferritin (SF) <15 ng/ml) were included in this study; 11 of them were anemic. As treatment, they received IFFWCM, instead of the customary whole cow's milk, for at least 4 months; medicinal iron was not administered. Hematocrit (Hct), hemoglobin (Hb), SI, TS, and SF were determined monthly. Results: The Hb increased from 10.3 +/- 0.8 to 12.7 +/- 0.6 g/dl in the group with anemia ([DELTA]F_B: 2.4 +/- 1.0 g/dl) and from 12.6 +/- 0.7 to 13.5 +/- 0.3 g/dl in the group without anemia ([DELTA]F_B: 0.9 +/- 0.5 g/dl); the difference between both groups was significant (p < 0.01); the rate for Hct values showed a similar pattern. In the whole group, the SI increased to 84.8 +/- 37.4 +/-g/dl, with no difference between children with anemia and children without anemia; TS showed a similar pattern ([DELTA]F_B: 19.0 +/- 11.0%). The mean SF increased from 12.1 +/- 2.7 ng/ml to 27.9 +/- 25.4 ng/ml. Normal values for Hct, Hb, SI, and TS were reached by 100% of children; the rate for SF was 56.3%. Time required to reach normal Hct in the children with anemia was 59.4 +/- 33.0 days. Acceptance and tolerance were excellent; no treatment had to be discontinued. The group of patients with anemia was compared with an historical group composed of 55 children matched for age, basal Hct, and achieved Hct increase, treated with medicinal FS (4-6 mg/kg/day): time required to reach normal Hct was shorter in the FS-treated group (39.0 +/- 14.5 days) (p = 0.050). Conclusion: The use of IFFWCM alone could be an effective, relatively inexpensive, and well-tolerated treatment of iron deficiency in children.
Stability of fortified whole wheat flour (WWF) was evaluated using NaFeEDTA, elemental iron, ZnSO4 and ZnO as fortificants. Fortified WWF was stored in tin boxes and polypropylene bags for 60 days under ambient storage condition (ASC) and controlled storage condition (CSC). Fortification significantly (p⩽0.05) decreased moisture and protein content and increased ash content to 5.44%, 6% and 23%, as compared to control. Fortified WWF, assayed periodically for mould contamination manifested a significant inhibition (∼1 log reduction) in flours containing elemental iron. Low storage temperature and relative humidity (RH) indicated lower level of mould count during extended storage time. Tin boxes, as storage material, exhibited a better protection against mould attack, acting as an effective barrier for moisture. Fortificants exerted a slight deteriorative effect on texture characteristics of the chapattis made of these flours but chapattis were still accepted by the judges. Zinc fortificants seemed like having little or no effect on the quality of the flours and chapattis, made of such flours. Shelf life of fortified flour may be extended by using elemental iron as fortificant and storing the product in tin boxes under relatively low temperature and RH.
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Dietary Reference Intakes (DRIs) represent the new approach adopted by the Food and Nutrition Board to providing quantitative estimates of nutrient intakes for use in a variety of settings, replacing and expanding on the past 50 years of periodic updates and revisions of the Recommended Dietary Allowances (RDAs). The DRI activity is a comprehensive effort undertaken to include current concepts about the role of nutrients and food components in long-term health, going beyond deficiency diseases. The DRIs consist of 4 reference intakes: the RDA, which is to be used as a goal for the individual; the Tolerable Upper Intake Level (UL), which is given to assist in advising individuals what levels of intake may result in adverse effects if habitually exceeded; the Estimated Average Requirement (EAR), the intake level at which the data indicate that the needs for 50% of those consuming it will not be met; and the Adequate Intake (AI), a level judged by the experts developing the reference intakes to meet the needs of all individuals in a group, but which is based on much less data and substantially more judgment than that used in establishing an EAR and subsequently the RDA. When an RDA cannot be set, an AI is given. Both are to be used as goals for an individual. Two reports have been issued providing DRIs for nutrients and food components reviewed to date: these include calcium and its related nutrients: phosphorus, magnesium, vitamin D, and fluoride; and most recently, folate, the B vitamins, and choline. The approaches used to determine the DRIs, the reference values themselves, and the plans for future nutrients and food components are discussed. J Am Diet Assoc. 1998;98: 699–706 .
To determine if double-fortified salt improved the haemoglobin levels and productivity of tea pickers, a double-blind, randomized, placebo-controlled trial was conducted on 793 tea pickers. The subjects in the experimental households (n = 385) received salt fortified with iron and iodine, and the subjects in the control households (n = 408) received common unfortified salt. Fingerprick blood analysis for haemoglobin by the cyanmethaemoglobin method was performed three times during a period of one year. The productivity data were also analysed for 450 tea pickers. At the end of the year, their average haemoglobin level had increased from 8.9 to 10.2 g/dl and their corresponding picking average had increased from 24.8 kg to 26.2 kg, which could increase annual tea production by 330 tonnes.
Premix containing ferrous sulfate, ethylenediamine tetraacetic acid and folic acid (20.0:20.0:1.5 ppm) was used to fortify whole wheat flour stored at ambient temperature for 42 days. Naans (flat bread) were prepared from 0-, 20-, 40- and 60-ppm ferrous iron-fortified flour samples at weekly intervals and were analyzed for physicochemical constants and sensory evaluation. It was observed that flour containing 60-ppm ferrous sulfate contained the highest iron residues. Total iron in flour samples showed no significant difference, while ferrous iron significantly decreased in fortified flour (0.53–3.08%) and in the naans (0.42–3.48%) because of its oxidation to ferric iron during storage. Phytic acid content decreased (0.886–0.810%) significantly during the same storage period. Iron levels affected some sensory characteristics significantly (P ≤ 0.05) including color, texture, flexibility, chewability and overall acceptability of the naans, but not taste and flavor. The sensory attributes of naans illustrated that naans containing 40-ppm ferrous iron are more acceptable than those prepared with 60-ppm ferrous iron.
The interactions between infections, malnutrition and poor iron nutritional status in infants at weaning ages are poorly defined. Therefore, four groups of infants from an area with a high incidence of malnutrition (Lahore, Pakistan) were enrolled in a prospective, randomized nutritional intervention study. Between 122 and 365 days of age, the infants from one community received either a milk cereal without iron fortification (n= 29), a milk cereal fortified with ferrous fumarate (7.5 mg/100 g; n= 30), or a milk cereal fortified with ferric-pyrophosphate (7.5 mg/100 g; n= 27). Forty-four infants from a neighbouring community did not receive a nutritional supplement and served as the control group. Calculated mean daily energy- and protein intake with the cereals was between 259–287 kcal, and 9.6–10.6 g at 12 months of age, respectively. Mean daily iron intake with the fortified cereals was between 4.1–5.1 mg at corresponding age. Nutritional supplementation resulted in significantly lower incidence of malnutrition and heigher weight gain. Incidence of acute diarrhoea was significantly (p<0.05) lower in the supplemented groups. The infants fed the iron-fortified milk cereals had significantly higher hemoglobin (mean 10.4 vs. 9.8 gdl-1) and serum ferritin (mean 13.3 vs. 8.5 ngml-1) values than the infants fed the non-fortified milk cereals. However, no differences in the incidence of infections were found between the supplemented groups. It is concluded that poor nutritional intake between 122 and 365 days of age substantially contributed to the high incidence of diarrhoea and malnutrition in Pakistani infants.
The relationship between high dietary iron intake, mutations of theHFE gene, and iron status, and their effects on human health are reviewed. Prolonged high dietary intakes of iron are unlikely to result in iron overload in the general population. Homozygotes for the C282Y mutation of theHFE gene have elevated body iron levels. Heterozygotes have normal iron stores but some may be at increased risk for cardiovascular disease. There is no convincing evidence that elevated iron status increases the risk of coronary heart disease or type 2 diabetes, but high iron intakes may increase the risk of colorectal cancer. The dietary levels of iron associated with health risks in differentHFE genotypes must be determined.
To determine if repletion of hemoglobin was achievable in young children presenting both severe (< or =9.4 g hemoglobin/dL blood) and less severe iron deficiency anemia (9.5 to 11.0 g hemoglobin/dL blood) through fortification of liquid 3.3% butterfat milk with a bioavailable ferrous iron amino acid chelate (Ferrochel) at 3 mg iron/liter/day.
A group of 185 children were selected from Tupã, Brazil who presented the above two stages of iron deficiency anemia plus normalcy. Initially, 54% had severe iron deficiency anemia, 33% were less severely anemic and 13% had normal hemoglobin concentrations. They received iron-fortified milk for a mean of 222+/-2 days. Hemoglobin concentrations were measured initially, at 133+/-13 days, and at 222+/-2 days.
By mean 222 days, 57% of the childrens' hemoglobins were normal. Highest rates of repletion were in the initially severe anemic group. Repeated measures ANOVAs demonstrated that hemoglobins at 0, 133 and 222 days for the total group, as well as for the severe and less severe iron deficiency anemic groups, represented statistically different populations at alpha=0.0005. Children with initially normal hemoglobin concentrations showed no change at 0, 133 and 222 days (alpha=0.10), suggesting the possibility of absorptive regulation of this form of iron.
Low hemoglobin concentrations in young children can be increased through daily consumption of fluid milk fortified with 3 mg ferrous amino acid chelate (Ferrochel).
Reliable methods for assessing the iron status of a population are essential for developing effective public health measures to combat iron deficiency. The hemoglobin concentration, transferrin saturation, free erythrocyte protoporphyrin, and serum ferritin are all useful but they vary widely in their specificity and sensitivity for detecting iron deficiency. In applying these laboratory parameters, the usual approach in nutritional surveys is to determine the percentage of values outside the normal range. As an alternative, a model is presented here that uses these measurements to estimate the distribution of iron stores in a population. This approach may be particularly useful for evaluating the effectiveness of iron supplementation and fortification programs.
The iron status of a population of 1564 subjects living in the northwestern United States was evaluated by measurements of transferrin saturation, red cell protoporphyrin, and serum ferritin. The frequency distribution of these parameters showed no distinct separation between normal and iron-deficient subjects. When only one of these three parameters was abnormal (transferrin saturation below 15%, red cell protoporphyrin above 100 mug/ml packed red blood cells, serum ferritin below 12 ng/ml), the prevalence of anemia was only slightly greater (10.9%) than in the entire sample (8.3%). The prevalence of anemia was increased to 28% in individuals with two or more abnormal parameters, and to 63% when all three parameters were abnormal. As defined by the presence of at least two abnormal parameters, the prevalence of iron deficiency in various populations separated on the basis of age and sex ranged from 3% in adolescent and adult males to 20% in menstruating women. It is concluded that the accuracy of detecting iron deficiency in population surveys can be substantially improved by employing a battery of laboratory measurements of the iron status.
A total of 65 children with mild iron deficiency anemia (IDA) were divided into 5 groups, and received 0, 25, 50, 100 and 150 mg/day of vitamin C (VC) respectively every day for 8 weeks. Hemoglobin, serum ferritin, free erythrocyte and hematocrit were determined every week. At a daily average intake of about 30 mg of VC and 7.5 mg of Fe, the results of the study indicate that: (1) VC supplement alone could effectively control children's IDA, and a dose-dependent relationship was observed. (2) 50 mg/day of VC is the most efficient dosage and 6 weeks is the shortest time for an effective therapy. (3) With a diet predominantly comprised of plant foods, it is suggested that appropriate dose of VC should be supplemented for the children during winter and spring in northeastern areas of China.
The interactions between infections, malnutrition and poor iron nutritional status in infants at weaning ages are poorly defined. Therefore, four groups of infants from an area with a high incidence of malnutrition (Lahore, Pakistan) were enrolled in a prospective, randomized nutritional intervention study. Between 122 and 365 days of age, the infants from one community received either a milk cereal without iron fortification (n = 29), a milk cereal fortified with ferrous fumarate (7.5 mg/100 g; n = 30), or a milk cereal fortified with ferric-pyrophosphate (7.5 mg/100 g; n = 27). Forty-four infants from a neighbouring community did not receive a nutritional supplement and served as the control group. Calculated mean daily energy- and protein intake with the cereals was between 259-287 kcal, and 9.6-10.6 g at 12 months of age, respectively. Mean daily iron intake with the fortified cereals was between 4.1-5.1 mg at corresponding age. Nutritional supplementation resulted in significantly lower incidence of malnutrition and higher weight gain. Incidence of acute diarrhoea was significantly (p less than 0.05) lower in the supplemented groups. The infants fed the iron-fortified milk cereals had significantly higher hemoglobin (mean 10.4 vs. 9.8 g.dl-1) and serum ferritin (mean 13.3 vs. 8.5 ng.ml-1) values than the infants fed the non-fortified milk cereals. However, no differences in the incidence of infections were found between the supplemented groups. It is concluded that poor nutritional intake between 122 and 365 days of age substantially contributed to the high incidence of diarrhoea and malnutrition in Pakistani infants.
Inflammatory disease as well as iron deficiency may play an important role in the cause of anemia in the United States. We evaluated the relationships between Fe deficiency, inflammatory disease, and anemia using data from of the First National Health and Nutritional Examination Survey (NHANES I). Fe nutrition index was based on the ratio of serum Fe to Fe-binding capacity (Fe:TIBC) and inflammatory index was based on erythrocyte sedimentation rate (ESR). Groups with the highest prevalence of anemia were younger children, young women, and elderly men. Fe deficiency (low Fe:TIBC) was most common among the anemic children and young women but rare in anemic elderly men. Conversely, inflammation (high ESR) was most common among anemic elderly individuals. The prevalence of anemia was more than twice as high in the lowest than in the highest income group. Relative contributions of Fe deficiency and inflammation to anemia did not differ substantially among income groups.
Iron deficiency is widely observed worldwide, yet, paradoxically, iron is the most plentiful heavy metal in the earth's crust. Although absorption of iron from the gastrointestinal tract is strictly controlled, excretion is limited to iron lost from exfoliation of skin and gastrointestinal cells, customary and abnormal blood loss, and menses. Individuals highly vulnerable to iron deficiency have high iron needs, as during growth or pregnancy; high iron loss, as during marked hemorrhage or excessive and/or frequent menstrual losses; or diets with low iron content or bioavailability. Food iron is classified as heme or nonheme. Approximately half of the iron in meat, fish, and poultry is heme iron. Depending on an individual's iron stores, 15% to 35% of heme iron is absorbed. Food contains more nonheme iron and, thus, it makes the larger contribution to the body's iron pool despite its lower absorption rate of 2% to 20%. Absorption of nonheme iron is markedly influenced by the levels of iron stores and by concomitantly consumed dietary components. Enhancing factors, such as ascorbic acid and meat/fish/poultry, may increase nonheme iron bioavailability fourfold.
A survey of the prevalence of anemia in women in developing countries was published in 1982 by WHO. It estimated the prevalence of nutritional anaemia in developing countries (other than China) at 60% in pregnant women and 47% in non-pregnant women. The prevalence of anaemia in all women of reproductive age was estimated at 49%. These results were updated and incorporated into the present review which is an attempt to present a picture of anaemia prevalence in all countries of the world, separately for each of a number of age/sex categories, including children, adolescents, adults and elderly people. Where sufficient data were available, global prevalence rates as well as the number of individuals affected were estimated.
Fifty-four anaemic preschool children, all consuming similar, purely vegetarian, diets were randomly divided equally into an experimental and a control group. The children in the experimental group received 100 mg ascorbic acid twice a day, with lunch and with dinner, for 60 days. The controls received sugar placebos. Initially and at the end of the intervention, haemoglobin (Hb) and red cell morphology were estimated in all children. The children who received ascorbic acid supplements showed a significant improvement in Hb level as well as in red cell morphology, while the controls showed no change. Chemical analysis of the diets of a subsample showed ascorbic acid intakes to be very low.
In one study a group of 10 young adult male volunteers were given two experimental diets, differing in fat content. In a second study another group of 12 such volunteers received two experimental diets differing in linoleic acid content. The retention of calcium, magnesium and iron was measured during the dietary periods, each lasting 1 month. Decreasing the fat intake from 42 to 22 energy % did not result in statistically significant changes of the mineral balance. An increase in linoleic acid intake from 4 to 16 energy % (at a constant level of fat intake of 42 energy %) caused a decrease in the iron balance from 3.3 to 2.3 mg/day (p less than 0.01), while the calcium and magnesium retention did not change significantly. During the high linoleic acid dietary period haemoglobin levels decreased from 9.6 to 9.1 mmol/1 and packed cell volume from 0.48 to 0.46 1/1 (p less than 0.001). This effect of linoleic acid on iron utilization needs further investigation.
The diagnostic usefulness in iron deficiency anemia of serum ferritin, red cell protoporphyrin (Epp), mean corpuscular volume, mean corpuscular hemoglobin (MCH), and transferrin saturation measurements has been studied in a population of 294 children aged 1 to 6 yr. Of the children studied 19% had hemoglobin below 11 g/dl. Iron deficiency, diagnosed by at least two abnormal independent laboratory parameters, was the cause of anemia in all except two cases. The Pearson correlation coefficient for hemoglobin was highest with MCH, followed in decreasing order of magnitude by MCV, Epp, transferrin saturation, and finally by ferritin. Sensitivity and specificity were highest for MCH and lowest for ferritin. Of anemic, iron deficient individuals 97 to 100% could be identified by low MCH, 88 to 100% by transferrin saturation, 66 to 83% by ferritin, and 61 to 74% by Epp. In contrast, only 0 to 6% of normal, nonanemic individuals had low MCH, 0 to 4% had high Epp, but 21 to 39% had low transferrin saturation and 25 to 39% had low ferritin. Although reduced serum ferritin in anemic individuals is good evidence of iron deficiency, a significant proportion of anemic iron-deficient patients is missed by this procedure rendering it less useful than other, less expensive laboratory methods.
The goal of detecting iron deficiency in children is to identify those whose Hb concentration will rise in response to treatment with iron. In a controlled treatment trial conducted among Eskimo children, we examined the effectiveness of various measures of iron nutrition in predicting a response to iron therapy (greater than 1.0 g/dl rise in Hb). A response was seen in 43%, and an additional 26% had an intermediate response (0.5 to 1.0 g/dl rise). When individual Hb values were expressed as SD scores of the Hb distribution of a reference population, a marked skew toward low scores was seen before treatment. After treatment, the distribution became more Gaussian, indicating that iron deficiency had been the major cause of anemia. Serum ferritin, transferrin saturation, and free erythrocyte protoporphyrin levels moved toward normal with treatment, however, none of the tests used was very effective in distinguishing individuals who would have a response t Hb from those who would not (sensitivities: 63 to 42%, specificities: 45 to 61%). Laboratory measures of iron nutrition were far more helpful in depicting the iron status of the population than they were in distinguishing iron-responsive from nonresponsive individuals.