Effects of prenatal iron status on child neurodevelopment and behavior: A systematic review

Iron deficiency and iron-deficiency anemia are the main worldwide nutritional disorders. A good level of prenatal iron is essential for the correct child neurodevelopment but this association has been poorly investigated. To gather the scientific evidence on the relation between prenatal iron status and child neurodevelopment. To emphasize the importance of personalize the dose and type of supplementation. Wide search strategy was performed in electronic databases for English language articles with no limitations as regards the language or date of publication. Additional studies were selected by hand search. The inclusion criteria were pregnant women without high-risk pregnancy and their children as study population and neurodevelopment as the main outcome. Six RCTs and 13 observational studies were included. The majority concluded that deficit or excess iron during pregnancy injures the mental and psychomotor development of child. Other authors found no association of low iron level with troubles in neurodevelopment, recommended multi-micronutrients instead of iron alone and/or showed inconsistent results. Both iron deficiency as its excess are harmful for the child neurodevelopment. The prenatal iron supplementation should be adjusted for each woman, taking into account the iron stores, some genetic mutation and other health habits.     

Effects of iron supplementation versus dietary iron on the nutritional iron status: Systematic review with meta-analysis of randomized controlled trials

ABSTRACT

This meta-analysis compared the effects of dietary intervention versus iron supplementation on biochemical parameters related to the iron nutritional status in humans. The PubMed, CENTRAL, LILACS, SCIELO, OPENGREY.EU and ClinicalTrials.gov databases were searched for randomized clinical trials that assigned individuals to a dietary intervention or to an iron supplementation regimen, for 12 weeks or more. The primary outcome was the hemoglobin concentration, and secondary outcomes were ferritin, RDW, mean corpuscular volume, soluble transferrin receptor, total iron binding capacity, serum iron, and transferrin saturation. From the 6095 records identified, twelve studies were included, six with children, five with adolescents/adults, and one with pregnant women. In the subgroup of studies that included anemic/iron deficient children, supplementation significantly increased the hemoglobin concentration (weighted mean difference (WMD): 3.19 g/L [95% CI: 1.31, 5.07]) and induced a significantly greater reduction of the soluble transferrin receptor (WMD: ?0.46 mg/L [95% CI: ?0.70, ?0, 21]), when compared to dietary intervention. It also induced a greater reduction of the total binding capacity of iron in adolescents/adults (WMD: ?6.96 μmol/L [95% CI: ?12.70, ?1.21]). Supplementation showed a better effect on hemoglobin recovery in anemic/iron deficient children, while no differences were observed between supplementation and dietary intervention in treating adolescents/adults.     

The connection between vitamin and iron status indexes of school-age children

The analysis of vitamin and iron indexes of 95 children sufficiently supplied with vitamin C and vitamin B2 and carotenoids deficiency has been carried out. Vitamin E deficit takes place among anemic children (with decreased hemoglobin blood level) 2 fold more often than among healthy children. From another side, decreased hemoglobin blood level, erythrocyte quantity and erythrocyte indexes have been determined 1.7-2.4 fold more often in insufficiently supplied with vitamin E children. Tocopherols serum level had tendency to the decrease and vitamin E deficit took place 2 fold more frequently in children suffering from iron deficiency anemia that is with decreased hemoglobin and serum ferritin concentrations. Marked positive linear correlation between these iron indexes and vitamin E serum level has been revealed. These results give evidence concerning significant role of this vitamin in the body iron supplying. The results obtained give evidence for multi-deficient anemia presence among children, which are not always caused by iron deficit. High frequency of vitamin E and B group vitamins deficiency proves expediency of these vitamins inclusion in complex therapy of iron deficiency.     

Vitamin D supplementation and non-alcoholic fatty liver disease: A critical and systematic review of clinical trials

Previous observational studies have found a relationship between vitamin D deficiency and non-alcoholic fatty liver disease (NAFLD). However, this type of study could not show the causal relationship between these two conditions. Therefore, we systematically and critically reviewed the available clinical trials to elucidate such relationship. We searched databases such as Medline, Scopus and Cochrane to identify the clinical trials that assessed the effects of vitamin D supplementation in adults with NAFLD. The outcome variables of interest were indicators of hepatic steatosis, liver enzymes, insulin resistance, inflammation and oxidative stress. A total of 6 studies were included in the qualitative analysis. Only in two studies the grade of hepatic steatosis decreased significantly after vitamin D supplementation. The changes in insulin resistance parameters were reported significant only in one. Of the 3 included studies that measured biomarkers of inflammation and oxidative stress, one revealed a significant decrease in these biomarkers after vitamin D supplementation. Findings from current review study provided new insight into the factors that could affect the therapeutic role of vitamin D in NAFLD. Factors such as gender differences, baseline serum status of vitamin D, co-supplementation with calcium and gene polymorphism should be considered when designing future clinical trials.     

Effectiveness of intermittent iron treatment of two- to six-year-old Jordanian children with iron-deficiency anemia

BACKGROUND: Iron deficiency is a common nutritional problem in young children among vulnerable populations in Jordan. Several studies have shown the effectiveness of intermittent iron supplementation in improving iron status. Such a study has not been carried out in 2- to-6-year-old Jordanian children diagnosed with iron deficiency anemia in a clinical setting. OBJECTIVE: To study the effectiveness of intermittent versus daily iron treatment in a clinical setting in 2- to 6-year-old Jordanian children with iron-deficiency anemia. METHODS: About 4400 children aged 2 to 6 years who visited Prince Hashim Military Hospital in Zarqa, Jordan, from August 2000 to June 2001 were screened for age, general health, and birthweight. About 10% of these children were screened for anemia, using complete blood count (defined as a hemoglobin level < or = 10.5 g/dL, and a mean corpuscular volume < or =75 ft). Anemic children underwent further screening for iron deficiency, defined as serum ferritin level < or =12 microg/L. Children with iron-deficiency anemia, as indicated by hemoglobin < or = 10.5 g/dL, mean corpuscular volume < or =75 fL, and serum ferritin < or =12 microg/L, or as indicated by mean corpuscular volume < or =75 fL and hemoglobin < or = 10.5 g/dL, were enrolled in the study after informed oral consent by their parents. Study children (n=134) were assigned randomly to one of three groups. Subjects in group 1 (n=45), group 2 (n=45), and group 3 (n=44) received iron treatment daily, weekly, and twice weekly, respectively. Out of 134 children recruited for the study, only 63 (39 boys and 24 girls) completed the 3-month treatment period. All of the children received medicinal iron drops at a dosage of 5 mg elemental iron as ferrous sulfate per kilogram of body weight. The parents also received nutritional counseling. RESULTS: At the end of treatment, hemoglobin, serum ferritin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration increased significantly in all groups with no significant differences between groups. The increases in hemoglobin in groups 1, 2, and 3 were 2.47 +/- 0.17, 2.12 +/- 0.18, and 2.18 +/- 0.18 g/dL, respectively. Measurements of final serum ferritin concentration were available for only 12, 12, and 10 children in groups 1, 2, and 3, respectively. In all children who completed the study, except for one in group 1, hemoglobin, mean corpuscular volume, and serum ferritin reached normal values in response to iron treatment. CONCLUSIONS: Weekly and twice-weekly iron therapy with 5 mg elemental iron as ferrous sulfate per kilogram of body weight accompanied by nutritional counseling was as effective as daily iron therapy in correcting iron-deficiency anemia in 2- to 6-year-old children under the clinical conditions of this study.     

A Quarter of a Century of Progress to Prevent Vitamin A Deficiency Through Supplementation

A quarter of century has passed since FRI published its first comprehensive review on vitamin A deficiency (VAD) and its prevention. At the time, the major impetus to prevent VAD was to reduce xerophthalmia in preschool children. Today, we have a broader understanding of the public health implications of VAD, with disorders including xerophthalmia, mortality, severe infection, and anemia in preschool children and pregnant women. While deficiency affects most developing countries, nearly half of all deficient children and women live in Southern Asia. Prevention has made substantial strides. High potency vitamin A supplementation (with 200,000 IU) remains a prophylactic mainstay, delivered through fixed facilities, enhanced outreach activities, and national child health day campaigns twice annually. Surprisingly, the costs of semi-annual delivery of vitamin A have changed little over the years, with new cost estimates remaining comparable to earlier figures of US ～$0.50 per child per year. Emerging is the potential to reduce infant mortality by ～20% in Southern Asia by giving a single, oral, 50,000 IU dose of vitamin A to newborns. While ～500 million vitamin A capsules are routinely distributed worldwide each year to achieve effective control, progress has been slower with efforts to improve diet on a purposeful global public health scale. Future advances through effective dietary diversification and various means of food fortification will be required before periodic supplementation can be phased down as a major population strategy for controlling vitamin A deficiency.     

Bioavailability of a Heme-Iron Concentrate Product Added to Chocolate Biscuit Filling in Adolescent Girls Living in a Rural Area of Mexico

ABSTRACT: A heme-iron concentrate product derived from swine hemoglobin was used to enrich the chocolate-flavored filling of biscuits and the bioavailability of this source of heme-iron was assessed in adolescent girls. The placebo control (PC) group consisted of 35 teenagers with the highest baseline hemoglobin concentrations. The supplemented groups were randomized to receive biscuits fortified with iron sulfate (IS, n = 37) or heme-iron concentrate (HIC, n = 40). Both groups were supplemented with 10.3 mg Fe/d for 7 wk. Blood chemistry and hematology analyses were performed at baseline and at the end of the study. The baseline prevalence of anemia (hemoglobin <12g/dl) in the entire group was 3.9% and by the end of the study it had fallen to 2.3%. The hemoglobin levels in both supplemented groups increased (P < 0.05) during the study period from 13.6 and 13.5 g/dl for HIC and IS, respectively, at baseline to 14 g/dl at the end of the study. Serum ferritin concentrations decreased by the end of the study in both the PC and IS groups (P < 0.05), but not in the heme group. In conclusion, iron bioavailability from HIC-fortified biscuits was calculated to be 23.7% higher than that observed for IS, as shown by the differences observed in serum ferritin levels during the study. The iron contained in the heme-iron concentrate was well absorbed and tolerated by the adolescents included in the study.     

An analysis of the etiology of anemia and iron deficiency in young women of low socioeconomic status in Bangalore, India

BACKGROUND: Anemia and iron deficiency are significant public health problems in India, particularly among women and children. Recent figures suggest that nearly 50% of young Indian women are anemic. OBJECTIVES: Few studies have comprehensively assessed etiologic factors contributing to anemia and iron deficiency in India. Hence, this study assessed the relative importance of various factors contributing to these problems in young women of low socioeconomic status in Bangalore, India. METHODS: A random sample of 100 nonpregnant, nonlactating women 18 to 35 years of age, selected from among 511 women living in a poor urban settlement, participated in this study. Data were obtained on demography, socioeconomic status, anthropometry, three-day dietary intake, blood hemoglobin, hemoglobinopathies, serum ferritin, serum C-reactive protein, and stool parasites. RESULTS: The prevalence rates of anemia and iron deficiency were 39% and 62%, respectively; 95% of the anemic women were iron deficient. The mean dietary iron intake was 9.5 mg per day, predominantly from the consumption of cereals, pulses, and vegetables (77%). The estimated bioavailability of nonheme iron in this diet was 2.8%. Dietary intakes were suboptimal for several nutrients. Blood hemoglobin was significantly correlated with dietary intake of fat, riboflavin, milk and yogurt, and coffee. Serum ferritin was significantly correlated with intake of niacin, vitamin B12, and selenium. Parasitic infestation was low. CONCLUSIONS: An inadequate intake of dietary iron, its poor bioavailability, and concurrent inadequate intake of dietary micronutrients appear to be the primary factors responsible for the high prevalence of anemia and iron deficiency in this population.     

Vitamin D and its impact on maternal-fetal outcomes in pregnancy: A critical review

The role of vitamin D beyond its classical function in calcium homeostasis has been of significant interest in recent years. There has been expanding research on the pleiotropic role of vitamin D in pregnancy and the implications of its deficiency on maternal-fetal outcomes. Several studies have associated low maternal vitamin D status to adverse outcomes in pregnancy, including preeclampsia, gestational diabetes, preterm births, low birth weight, and others. Several randomized controlled clinical trials of Vitamin D supplementation during pregnancy have also been conducted. Though some of the studies found improvement in pregnancy outcomes with vitamin D supplementation, others have not shown any association. In this article, we have critically reviewed the observational and interventional studies, published primarily within the past two years (January 2014 to February 2016) on the influence of vitamin D deficiency on pregnancy and the impact of its supplementation. The potential underlying mechanisms of vitamin D in regulating each of the outcomes have also been discussed.     

Vitamin A: Deficiency and Food-Based Combating Strategies in Pakistan and Other Developing Countries

Vitamin A deficiency is a world wide nutritional problem especially in the developing countries that afflicts severely the health of pregnant and lactating women, infants and children. Women are the most vulnerable group affected by vitamin A deficiency during their pregnancy and lactating periods. Different strategies like food diversification, fortification, and supplementation are helpful to cope with vitamin A deficiency. Food fortification is the most cost effective, long-term approach, while supplementation is considered to be the fastidious way to uplift vitamin A status. Generally Retinyl acetate and retinyl palmitate are used in different food products as fortificants against the Vitamin A menace. In addition to these food-based strategies, educating the people regarding health and nutrition can also play an effective role.     

Vitamin A: Deficiency and Food-Based Combating Strategies in Pakistan and Other Developing Countries

Vitamin A deficiency is a world wide nutritional problem especially in the developing countries that afflicts severely the health of pregnant and lactating women, infants and children. Women are the most vulnerable group affected by vitamin A deficiency during their pregnancy and lactating periods. Different strategies like food diversification, fortification, and supplementation are helpful to cope with vitamin A deficiency. Food fortification is the most cost effective, long-term approach, while supplementation is considered to be the fastidious way to uplift vitamin A status. Generally Retinyl acetate and retinyl palmitate are used in different food products as fortificants against the Vitamin A menace. In addition to these food-based strategies, educating the people regarding health and nutrition can also play an effective role.     

Anemia prevalence and risk factors in pregnant women in an urban area of Pakistan

BACKGROUND: Anemia affects almost two-thirds of pregnant women in developing countries and contributes to maternal morbidity and mortality and to low birthweight. OBJECTIVE: To determine the prevalence of anemia and the dietary and socioeconomic factors associated with anemia in pregnant women living in an urban community setting in Hyderabad, Pakistan. METHODS: This was a prospective, observational study of 1,369 pregnant women enrolled at 20 to 26 weeks of gestation and followed to 6 weeks postpartum. A blood sample was obtained at enrollment to determine hemoglobin levels. Information on nutritional knowledge, attitudes, and practice and dietary history regarding usual food intake before and during pregnancy were obtained by trained interviewers within 1 week of enrollment. RESULTS: The prevalence of anemia (defined by the World Health Organization as hemoglobin < 11.0 g/dL) in these subjects was 90.5%; of these, 75.0% had mild anemia (hemoglobin from 9.0 to 10.9 g/dL) and 14.8% had moderate anemia (hemoglobin from 7.0 to 8.9 g/dL). Only 0.7% were severely anemic (hemoglobin < 7.0 g/ dL). Nonanemic women were significantly taller, weighed more, and had a higher body mass index. Multivariate analysis after adjustment for education, pregnancy history, iron supplementation, and height showed that drinking more than three cups of tea per day before pregnancy (adjusted prevalence odds ratio [aPOR], 3.2; 95% confidence interval [CI], 1.3 to 8.0), consumption of clay or dirt during pregnancy (aPOR, 3.7; 95% CI, 1.1 to 12.3), and never consuming eggs or consuming eggs less than twice a week during pregnancy (aPOR, 1.7; 95% CI, 1.1 to 2.5) were significantly associated with anemia. Consumption of red meat less than twice a week prior to pregnancy was marginally associated with anemia (aPOR, 1.2; 95% CI, 0.8 to 1.8) but was significantly associated with lower mean hemoglobin concentrations (9.9 vs. 10.0 g/dL, p = .05) during the study period. A subanalysis excluding women with mild anemia found similar associations to those of the main model, albeit even stronger. CONCLUSIONS: A high percentage of women at 20 to 26 weeks of pregnancy had mild to moderate anemia. Pica, tea consumption, and low intake of eggs and red meat were associated with anemia. Women of childbearing age should be provided nutritional education regarding food sources of iron, especially prior to becoming pregnant, and taught how food choices can either enhance or interfere with iron absorption.     

Impact of fortification of flours with iron to reduce the prevalence of anemia and iron deficiency among schoolchildren in Caracas, Venezuela: a follow-up

In Venezuela, a severe economic crisis starting in 1983 provoked a progressive reduction in the quantity and quality of food consumed by people from the low socioeconomic strata of the population. This situation resulted in a continuous increase in the prevalence of iron deficiency in the 1980s and 1990s. In 1993, an iron-fortification program was started, in which precooked corn and white wheat flours were enriched with iron, vitamin A, thiamine, niacin, and riboflavin. White wheat flour was enriched with the same nutrients, except for vitamin A. In 1996 we published the results of the impact of fortification of precooked corn and white wheat flours on the prevalence of anemia and iron deficiency in the population. A survey carried out in Caracas in 307 children aged 7, 11, and 15 years showed that the prevalence of iron deficiency measured by serum ferritin concentration dropped from 37% in 1992 to 16% in 1994, only one year after the iron-fortification program began. The prevalence of anemia, as measured by the hemoglobin concentration, diminished from 19% to 10% during the same period. This article reports the results of three other surveys carried out in 1997, 1998, and 1999 on children of the same age and socioeconomic groups that were evaluated in 1990, 1992, and 1994. There were no significant differences in anemia or iron deficiency among the last three surveys. The prevalence results from the last seven years seem to indicate that, after a dramatic reduction in 1994, iron deficiency tended to stabilize, while the prevalence of anemia increased to the same level found in 1992, before the fortification program started.     

Food frequency questionnaire for assessing infant iron nutrition.

A food frequency questionnaire (FFQ) was developed and tested for assessing iron nutrition in infants through comparison with a three-day food record (3d-FR) and measures of iron status. Parents of 148 infants aged eight to 26 months completed a 3d-FR and an FFQ. Blood was collected for measures of hemoglobin (Hgb), ferritin, and transferrin receptor (sTfR). Iron deficiency anemia and iron depletion (ferritin < or =12 microg/L) were found in 9% and 26% of infants, respectively. The intakes of energy, total iron, heme and non-heme iron, vitamin C, and dietary fibre determined by the FFQ were associated with the intakes of the same nutrient determined by the 3d-FR (p<0.05). The intakes of energy, total iron, non-heme and heme iron, vitamin C, and fibre were significantly higher when estimated by the FFQ than by the 3d-FR. Total and heme iron intakes determined by the FFQ were significantly associated with serum ferritin, sTfR, and the sTfR:ferritin ratio (p<0.05). However, iron intakes explained <10% of the variability in iron status. Despite relative validity of the FFQ for evaluating differences in energy, iron, vitamin C, and fibre intake compared with a 3d-FR, FFQs need further development before they can be used to advance assessment of iron intake and status in infants.     

Structure,Function, and Nutrition of Phytoferritin: A Newly Functional Factor for Iron Supplement

Ferritins are members of the superfamily of iron storage and detoxification proteins present in all living organisms and play important roles in controlling cellular iron homeostasis. In contrast to animal ferritin, relatively little information is available on the structure and function of phytoferritin. Phytoferritin is observed in plastids whereas animal ferritins are largely found in the cytoplasm of cell. Compared to animal ferritin, phytoferritin exhibits two major distinctive features in structure. First, phytoferritin contains a specific extension peptide (EP) at the N-terminal while animal ferritin lacks it. The EP is located on the exterior surface of protein, which recently has been found to act as a second ferroxidase center for iron-binding and oxidation, and regulate iron release during the germination and early growth of seedlings. Second, only H-type subunit has been identified in phytoferritin, which is usually a heteropolymer consisting of two different subunits, H-1 and H-2, sharing ～80% amino acid sequence identity. These two subunits in phytoferritin play a positively cooperative role in iron oxidative deposition in protein. Iron deficiency anemia (IDA) is the most common and widespread nutritional disorder in the world, so it is crucial to explore a safe and efficient functional factor for iron supplement. Fortunately, phytoferritin seems to be a suitable candidate. In legume seeds, more than 90% of iron is stored in the form of ferritin in amyloplasts. Recently, some studies at different levels have demonstrated that plant ferritin could be used as novel, utilizable, plant-based forms of iron for populations with a low iron status. This review focuses on recent progress in structure, function, and nutrition of phytoferritin.     

Lessons from successful micronutrient programs. Part III: program impact

Micronutrient-deficiency control programs have been greatly extended at the national level in the last 10 to 15 years. However, rigorous evaluations of these are scarce, so that conclusions on impact are tentative and based mainly on indirect evidence. The coverage of vitamin A capsule distribution programs has exceeded 70% in most study countries. In countries implementing national iodized salt programs, the coverage reaches 60% to 90% of households with adequately iodized salt. Of the three micronutrients, coverage of iron tablet supplementation is the least well documented due to inadequate program monitoring systems and population survey data. Supplementation of preschool children 6 to 59 months of age with vitamin A capsules has plausibly contributed to the reduction in clinical vitamin A deficiency and its near-elimination in many countries. The impact of vitamin A capsule supplementation on children's biochemical vitamin A status (serum retinol) in national programs may be less. National data on salt iodization show a consistent relation to reduced prevalence of iodine-deficiency disorder symptoms (goiter); the rates of cretinism and other results of iodine deficiency are almost certainly falling too. The evaluation of the impact of salt iodization programs on biochemical iodine status is limited by a lack of data. Although trials have demonstrated the efficacy of iron supplementation in reducing the prevalence of anemia, the interpretation of national-level data is not so clear. Given the substantial financial and technical commitment required to implement national micronutrient-deficiency control programs, it is vital that investment enable the evaluation of the impact of these programs. It is becoming increasingly important to collect data on subclinical deficiency (e.g., biochemical data) to assess program impact.     

铁蛋白铁释放机理的研究进展

铁蛋白是一种广泛存在于生命体中的铁贮藏蛋白,具有调节机体铁代谢平衡和去除二价铁毒性的双重功能。缺铁严重影响着全球近一半人的健康,研究表明,铁蛋白具有良好的补铁活性而且安全、高效,能够取代具有毒副作用的传统补铁试剂。因此,寻求并开发以铁蛋白为原料的新型补铁功能食品已成为一种趋势。为了更科学地应用于实践和开发,对铁蛋白理化性质及其生物学功能的阐明显得颇为重要。目前,关于铁蛋白铁释放机理的研究分为体外和体内两个方面,体外机理涉及还原剂和螯合剂的共同作用,而体内机理主要涉及降解途径和酶介导的还原释放途径。综述了国内外有关铁蛋白铁释放机理的研究进展,以期为新型补铁功能食品的开发提供理论依据。     

Study on iron availability from prepared soybean sprouts using an iron-deficient rat model

During soya seeds germination in FeSO₄ solutions their phytoferritin content is multiplied. Prepared soybean sprouts have been proposed as a safe and easily available source of iron supplementation. The preparation was compared with FeSO₄ and ferritin isolates, using rats with induced iron deficiency anaemia. After the end of the 2-week supplementation experiment, it was observed that no statistically significant differences in haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration existed between those animals supplemented with sprouts enriched in ferritin, ferritin isolate and FeSO₄ and healthy animals forming the control group. Moreover, the examined preparation had a beneficial influence on the recreation of ferritin reserves in both the liver and the blood serum, and also did not induce negative alterations in general growth parameters of animals. Use of an easily obtainable ferritin iron source may be a profitable alternative in supplementation due to its wide availability and food preservative properties.     

Studies on iron deficiency anemia, rickets and zinc deficiency and their prevention among Chinese preschool children.

The incidence of iron deficiency anemia, rickets, and zinc deficiency is very high in Chinese preschool children and a method for prevention is urgently needed. From our studies, it can be seen that a soft drink powder is a convenient vehicle for the supplementation of iron, zinc, calcium, vitamin D, riboflavin, and ascorbic acid. Table salt is also a good, low-cost carrier for iron and zinc, and cow's milk can only be used for the enrichment of vitamins A and D. In our study the therapeutic dose of iron was lower than 3 mg/kg body weight recommended by the WHO Expert Committee. As ascorbic acid can enhance the absorption of iron in the body, so 300 mg vitamin C was added to 100 g of soft drink powder containing 100 mg of elemental iron. Ten g of powder is not only enough for the prevention of iron deficiency anemia but it can also cure iron deficiency anemia within 3 months. One hundred mg of iron in 100 g of table salt is an adequate level, because an adult or a child taking 10 or 5 g of salt will receive 10 and 5 mg of elemental iron respectively. This dosage is adequate for the prevention of anemia. From our results, 10 mg of zinc daily is enough for the prevention and treatment of zinc deficiency in preschool children. Four hundred IU of vitamin D (from fortified soft drink powder or enriched fresh cow's milk) orally-administered daily, is a good way to prevent rickets in infants and young children.     

铁蛋白铁氧化沉淀机理研究进展

铁素的缺乏严重影响着全球近一半人的健康,传统的补铁制剂由于会时人体产生副作用逐渐被禁止使用,因此,寻找安全、高效的补铁制剂势在必行.铁蛋白是广泛存在于生物体中的一种铁贮藏蛋白,它具有去除铁的毒性以及调节铁代谢平衡的双重功能.研究表明,铁蛋白具有良好的补铁活性,所以它可以作为加工原料被开发成补铁型功能食品,为此,对铁蛋白理化性质及其生物学功能的阐明就显得颇为重要.目前,有关铁蛋白的基础研究主要集中于铁蛋白的铁氧化沉淀和还原释放机理的研究,相对于后者而言,铁蛋白铁氧化沉淀机理的研究比较清楚.本文综述了国内外有关铁蛋白铁氧化沉淀机理的研究进展,以期为以后新型补铁功能食品的开发提供理论依据.