Assessment of Gastrointestinal Symptoms and Non-transferrin Bound Iron After Oral Ferrous Sulfate and Iron-enriched Aspergillus Oryzae Supplementation in Women (P24-039-19)

Objectives

Iron deficiency anemia (IDA) is a widespread nutritional deficiency. Iron supplementation with ferrous sulfate (FeSO4) is the most common strategy to treat IDA; however, the compliance with daily FeSO4 administration is poor, due to contraindicating side effects. Previously, we have reported that A. oryzae (Ultimine®; ULT) is a novel iron source. Therefore, the objective of this study was to determine the biochemical assessment, non-transferrin bound iron (NTBI) and commonly related gastrointestinal side effects to assess the safety of A. oryzae compared to FeSO4.

Methods

Female participants (n = 16) with serum ferritin concentrations 40 µg/L were randomized to a double-blind, 9-wk cross-over study with a 3-wk placebo washout period between treatments. Oral iron supplements (65 mg Fe), FeSO4 and ULT were administered for 21 consecutive days for each subject. Side effect questionnaires were collected 3d/wk over the 9-wk study period. Side effects and biochemical markers (nausea, heartburn, abdominal pain, fatigue, headache, diarrhea, constipation, oxidative stress and liver and kidney function) from iron supplementation were evaluated, along with serum iron, % transferrin saturation (TS) and NBTI 8 h curves.

Results

Serum iron, TS, and NTBI were all markedly higher with FeSO4 at each time-point from 2–8 hours (P < 0.001) compared to ULT, whereas NTBI was undetected. Among treatments, FeSO4 resulted in higher inflammation, though not statistically significant. Compliance based on returned pills was higher with ULT (97.3%) than placebo and FeSO4 (95.2% and 93.2%, respectively). Subjects taking FeSO4 reported abdominal discomfort 2% more than ULT, which was not significantly different. FeSO4 caused marginally higher incidence of combined nauseation, constipation and diarrhea when subjects were taking FeSO4 (P < 0.07). Iron status was maintained similarly by both oral iron supplements. Oxidative stress, inflammation, kidney and liver function markers were not elevated with ULT supplementation, suggesting safety of its consumption.

Conclusions

Better compliance and less gastrointestinal related side effects were reported with ULT compared to FeSO4, while maintaining normal iron status. Our data suggests ULT is a safe oral iron supplement for treatment of IDA.

Funding Sources

Cura Global Health, Inc.

Zinc Absorption From Agronomically Biofortified Wheat Is Similar to Post-Harvest Fortified Wheat and Is a Substantial Source of Bioavailable Zinc in Humans

BACKGROUND

Limited data exist on human zinc absorption from wheat biofortified via foliar (FBW) or root (hydroponically fortified wheat, HBW) zinc application. Stable isotope labels added at point of consumption (extrinsic labeling) might not reflect absorption from native zinc obtained by intrinsic labeling.

OBJECTIVES

We measured fractional and total zinc absorption (FAZ, TAZ) in FBW and HBW wheat, compared with control wheat (CW) and fortified wheat (FW). The effect of labeling method was assessed in HBW (study 1), and the effect of milling extraction rate (EXR, 80% and 100%) in FBW (studies 2 and 3).

METHODS

Generally healthy adults (n = 71, age: 18-45 y, body mass index: 18.5-25 kg/m2) were allocated to 1 of the studies, in which they served as their own controls. In study 1, men and women consumed wheat porridges colabeled intrinsically and extrinsically with 67Zn and 70Zn. In studies 2 and 3, women consumed wheat flatbreads (chapatis) labeled extrinsically. Zinc absorption was measured with the oral to intravenous tracer ratio method with a 4-wk wash-out period between meals. Data were analyzed with linear mixed models.

RESULTS

In study 1 there were no differences in zinc absorption from extrinsic versus intrinsic labels in either FW or HBW. Similarly, FAZ and TAZ from FW and HBW did not differ. TAZ was 70-76% higher in FW and HBW compared with CW (P < 0.01). In studies 2 and 3, TAZ from FW and FBW did not differ but was 20-48% higher compared with CW (P < 0.001). Extraction rate had no effect on TAZ.

CONCLUSIONS

Colabeling demonstrates that extrinsic zinc isotopic labels can be used to accurately quantify zinc absorption from wheat in humans. Biofortification through foliar zinc application, root zinc application, or fortification provides higher TAZ compared with unfortified wheat. In biofortified wheat, extraction rate (100-80%) has a limited impact on total zinc absorption. These studies were registered on clinicaltrials.gov (NCT01775319).

Iron bioavailability in 8-24-month-old Thai children from a micronutrient-fortified quick-cooking rice containing ferric ammonium citrate or a mixture of ferrous sulphate and ferric sodium ethylenediaminetetraacetic acid

A quick-cooking rice, produced from broken rice, is a convenient ingredient for complementary foods in Thailand. The rice is fortified with micronutrients including iron during the processing procedure, which can cause unacceptable sensory changes. A quick-cooking rice fortified with ferric ammonium citrate (FAC) or a mixture of ferrous sulphate (FeSO4 ) and ferric sodium ethylenediaminetetraacetic acid (NaFeEDTA), with a 2:1 molar ratio of iron from FeSO4  : iron from NaFeEDTA (FeSO4  + NaFeEDTA), gave a product that was organoleptically acceptable. The study compared iron absorption by infants and young children fed with micronutrient-fortified quick-cooking rice containing the test iron compounds or FeSO4 . Micronutrient-fortified quick-cooking rice prepared as a traditional Thai dessert was fed to two groups of 15 8-24-month healthy Thai children. The iron fortificants were isotopically labelled with (57) Fe for the reference FeSO4 or (58) Fe for the tested fortificants, and iron absorption was quantified based on erythrocyte incorporation of the iron isotopes 14 days after feeding. The relative bioavailability of FAC and of the FeSO4  + NaFeEDTA was obtained by comparing their iron absorption with that of FeSO4 . Mean fractional iron absorption was 5.8% [±standard error (SE) 1.9] from FAC and 10.3% (±SE 1.9) from FeSO4  + NaFeEDTA. The relative bioavailability of FAC was 83% (P = 0.02). The relative bioavailability of FeSO4  + NaFeEDTA was 145% (P = 0.001). Iron absorption from the rice containing FAC or FeSO4  + NaFeEDTA was sufficiently high to be used in its formulation, although iron absorption from FeSO4  + NaFeEDTA was significantly higher (P < 0.00001).

Integration to Implementation and the Micronutrient Forum: A Coordinated Approach for Global Nutrition. Case Study Application: Safety and Effectiveness of Iron Interventions

Paramount among the challenges to our ability to address the role of food and nutrition in health promotion and disease prevention is how to design and implement context-specific interventions and guidance. The Integration to Effective Implementation (I-to-I) concept is intended to address the complexities of the global health context through engagement of the continuum of stakeholders involved in the food and nutrition enterprise. The 2014 Micronutrient Forum (MNF) Global Conference held in Addis Ababa, Ethiopia, in June 2014 offered the opportunity to apply the I-to-I approach with the use of current concerns about the safety and effectiveness of interventions to prevent and treat iron deficiency (ID) as a case study. ID is associated with a range of adverse outcomes, especially in pregnant and nonpregnant women, infants, and primary school-age children. Strategies to combat ID include iron supplementation, multiple micronutrient powders, and food-based interventions to enhance dietary iron intake. Recent reports indicate potential increased adverse risks when iron is provided in areas with high infection burdens (e.g., malaria). This paradox has weakened iron intervention programs. Furthermore, the selection and interpretation of available biomarkers for assessing iron nutrition have been found to be compromised by the inflammatory process. These issues highlight the need for a comprehensive approach that considers basic biology, assessment, interventions, and how these can be translated into appropriate programs and policies. The application of the I-to-I with the use of the MNF offered an opportunity to explore how that might be achieved.

Modeling Zinc Intake for Intervention and Scenario Analysis

BACKGROUND

A large number of illnesses, afflicting one-third of the world's population, have been attributed to zinc deficiency. Inadequate dietary intake of bioavailable forms of zinc is considered the most frequent cause of zinc deficiency, which is most common in arid regions of developing countries.

OBJECTIVE

To employ a modeling approach in a test population to analyze how best to eliminate zinc deficiency using different plausible dietary scenarios.

METHODS

A comprehensive database was built upon food consumption patterns of two population groups residing in a village and a suburb in semiarid central Iran near Isfahan city. A database was created on zinc and phytic acid concentrations of different foods and ingredients consumed by the study populations. A zinc intake model was constructed and parameterized accounting for bioavailability and model input uncertainties.

RESULTS

The zinc intake of about one-third of both study populations, which did not differ significantly in their rates of zinc deficiency, was below the Estimated Average Requirement (EAR) for zinc. Scenario analyses predicted that at the current rate of food consumption, it would take up to 60 years for 97.5% of the population to meet their zinc EARs. Fortification of wheat flour and biofortification of wheat grains would result in 93% and 88% of the population, respectively, achieving their EARs in 15 years.

CONCLUSIONS

The modeled results suggest that fortification and biofortification are the most effective and sustainable strategies to combat zinc deficiency. The methodology developed in this study is general and is shown to be a useful tool for the analysis of possible future trends and intervention scenarios.

Phytic acid concentration influences iron bioavailability from biofortified beans in Rwandese women with low iron status

BACKGROUND

The common bean is a staple crop in many African and Latin American countries and is the focus of biofortification initiatives. Bean iron concentration has been doubled by selective plant breeding, but the additional iron is reported to be of low bioavailability, most likely due to high phytic acid (PA) concentrations.

OBJECTIVE

The present study evaluated the impact of PA on iron bioavailability from iron-biofortified beans.

METHODS

Iron absorption, based on erythrocyte incorporation of stable iron isotopes, was measured in 22 Rwandese women who consumed multiple, composite bean meals with potatoes or rice in a crossover design. Iron absorption from meals containing biofortified beans (8.8 mg Fe, 1320 mg PA/100 g) and control beans (5.4 mg Fe, 980 mg PA/100 g) was measured with beans containing either their native PA concentration or with beans that were ∼50% dephytinized or >95% dephytinized.

RESULTS

The iron concentration of the cooked composite meals with biofortified beans was 54% higher than in the same meals with control beans. With native PA concentrations, fractional iron absorption from the control bean meals was 9.2%, 30% higher than that from the biofortified bean meals (P < 0.001). The quantity of iron absorbed from the biofortified bean meals (406 μg) was 19% higher (P < 0.05) than that from the control bean meals. With ∼50% and >95% dephytinization, the quantity of iron absorbed from the biofortified bean meals increased to 599 and 746 μg, respectively, which was 37% (P < 0.005) and 51% (P < 0.0001) higher than from the control bean meals.

CONCLUSIONS

PA strongly decreases iron bioavailability from iron-biofortified beans, and a high PA concentration is an important impediment to the optimal effectiveness of bean iron biofortification. Plant breeders should focus on lowering the PA concentration of high-iron beans. This trial was registered at clinicaltrials.gov as NCT01521273.

Review on iron and its importance for human health

It is well-known that deficiency or over exposure to various elements has noticeable effects on human health. The effect of an element is determined by several characteristics, including absorption, metabolism, and degree of interaction with physiological processes. Iron is an essential element for almost all living organisms as it participates in a wide variety of metabolic processes, including oxygen transport, deoxyribonucleic acid (DNA) synthesis, and electron transport. However, as iron can form free radicals, its concentration in body tissues must be tightly regulated because in excessive amounts, it can lead to tissue damage. Disorders of iron metabolism are among the most common diseases of humans and encompass a broad spectrum of diseases with diverse clinical manifestations, ranging from anemia to iron overload, and possibly to neurodegenerative diseases. In this review, we discuss the latest progress in studies of iron metabolism and bioavailability, and our current understanding of human iron requirement and consequences and causes of iron deficiency. Finally, we discuss strategies for prevention of iron deficiency.

Genetic reduction of phytate in common bean (Phaseolus vulgaris L.) seeds increases iron absorption in young women

Iron bioavailability from common beans is negatively influenced by phytic acid (PA) and polyphenols (PPs). Newly developed low-PA (lpa) beans with 90% less PA and variable PPs might improve iron bioavailability. The aim of this study was to evaluate the influence of lpa beans on iron bioavailability in women (n = 20). We compared iron absorption from 4 different beans using a paired, double meal, crossover design. Iron absorption was measured as erythrocyte incorporation of stable iron isotopes (Fe(57), Fe(58)) from 2 lpa bean lines, one high in PPs (means ± SDs; PA = 124 ± 10 mg/100 g; PPs = 462 ± 25 mg/100 g) and one low in PPs (PA = 70 ± 10 mg/100 g; PPs = 54 ± 2 mg/100 g). The other 2 beans used were their parents with a normal PA concentration, one high in PPs (PA = 1030 ± 30 mg/100 g; PPs = 676 ± 19 mg/100 g) and one low in PPs (PA = 1360 ± 10 mg/100 g; PPs = 58 ± 1 mg/100 g). Fractional iron absorption from the lpa bean high in PPs was 6.1% (95% CI: 2.6, 14.7), which was 60 and 130% higher compared with the parent high in PPs (P < 0.001) and low in PPs (P < 0.001), respectively. The total amount of iron absorbed per test meal from the lpa bean high in PPs (372 μg; 95% CI: 160, 890) was 60 and 163% higher compared with the parent high in PPs (P < 0.001) and low in PPs (P < 0.001), respectively. Fractional iron absorption from the lpa line low in PPs (4%; 95% CI: 1.8, 8.7) was 50% higher and the total amount of iron absorbed per test meal (261 μg; 95% CI: 120, 570) was 85% higher than iron from the parent low in PPs (P < 0.001). There was no difference between the lpa beans high or low in PPs or between the parents high or low in PPs. A 90% reduction in PA leads to an increase in bioavailable iron from beans, independent of the PP concentration. The lpa mutation could be a key tool for improving iron bioavailability from beans.

Zinc and its importance for human health: An integrative review

Since its first discovery in an Iranian male in 1961, zinc deficiency in humans is now known to be an important malnutrition problem world-wide. It is more prevalent in areas of high cereal and low animal food consumption. The diet may not necessarily be low in zinc, but its bio-availability plays a major role in its absorption. Phytic acid is the main known inhibitor of zinc. Compared to adults, infants, children, adolescents, pregnant, and lactating women have increased requirements for zinc and thus, are at increased risk of zinc depletion. Zinc deficiency during growth periods results in growth failure. Epidermal, gastrointestinal, central nervous, immune, skeletal, and reproductive systems are the organs most affected clinically by zinc deficiency. Clinical diagnosis of marginal Zn deficiency in humans remains problematic. So far, blood plasma/serum zinc concentration, dietary intake, and stunting prevalence are the best known indicators of zinc deficiency. Four main intervention strategies for combating zinc deficiency include dietary modification/diversification, supplementation, fortification, and bio-fortification. The choice of each method depends on the availability of resources, technical feasibility, target group, and social acceptance. In this paper, we provide a review on zinc biochemical and physiological functions, metabolism including, absorption, excretion, and homeostasis, zinc bio-availability (inhibitors and enhancers), human requirement, groups at high-risk, consequences and causes of zinc deficiency, evaluation of zinc status, and prevention strategies of zinc deficiency.

Zinc and its importance for human health: An integrative review

Since its first discovery in an Iranian male in 1961, zinc deficiency in humans is now known to be an important malnutrition problem world-wide. It is more prevalent in areas of high cereal and low animal food consumption. The diet may not necessarily be low in zinc, but its bio-availability plays a major role in its absorption. Phytic acid is the main known inhibitor of zinc. Compared to adults, infants, children, adolescents, pregnant, and lactating women have increased requirements for zinc and thus, are at increased risk of zinc depletion. Zinc deficiency during growth periods results in growth failure. Epidermal, gastrointestinal, central nervous, immune, skeletal, and reproductive systems are the organs most affected clinically by zinc deficiency. Clinical diagnosis of marginal Zn deficiency in humans remains problematic. So far, blood plasma/serum zinc concentration, dietary intake, and stunting prevalence are the best known indicators of zinc deficiency. Four main intervention strategies for combating zinc deficiency include dietary modification/diversification, supplementation, fortification, and bio-fortification. The choice of each method depends on the availability of resources, technical feasibility, target group, and social acceptance. In this paper, we provide a review on zinc biochemical and physiological functions, metabolism including, absorption, excretion, and homeostasis, zinc bio-availability (inhibitors and enhancers), human requirement, groups at high-risk, consequences and causes of zinc deficiency, evaluation of zinc status, and prevention strategies of zinc deficiency.

Inulin modifies the bifidobacteria population, fecal lactate concentration, and fecal pH but does not influence iron absorption in women with low iron status

BACKGROUND

Bioavailability of nonheme iron is influenced by the concentration of inhibitors and enhancers in the diet. The fructans inulin and oligofructose have been shown to improve iron absorption in animals through colonic uptake, but this has not been confirmed in humans.

OBJECTIVE

The aim of the intervention study was to evaluate the influence of inulin on iron absorption, bifidobacteria, total bacteria, short-chain fatty acids (SCFAs), and fecal pH in women with low iron status (plasma ferritin <25 μg/L).

DESIGN

The subjects (n = 32) consumed inulin or placebo 3 times/d (∼20 g/d) for 4 wk, separated by a 2-wk washout period. Iron absorption was measured after 3 wk of inulin and placebo consumption from a standard test meal by using stable-iron-isotope techniques. Fecal bacteria were measured by quantitative polymerase chain reaction, and fecal acids by HPLC.

RESULTS

Mean fractional iron absorption in the inulin (15.2%; 95% CI: 8.0%, 28.9%) and placebo (13.3%; 95% CI: 8.1%, 24.3%) periods did not differ significantly (P = 0.10). Inulin decreased fecal pH (P < 0.001) and increased fecal bifidobacteria (P < 0.001) and fecal lactate (P < 0.001) but had no effect on fecal SCFAs and total bacteria. Changes in lactate and acetate concentrations were positively correlated with changes in propionate (P < 0.001) and butyrate (P < 0.02) concentrations, respectively. Iron absorption correlated with fecal pH in the placebo period (P < 0.01) but not in the inulin period (P = 0.37).

CONCLUSION

Although inulin showed prebiotic activity, we were unable to show an increase in iron absorption in women with low iron status. This trial was registered at clinicaltrials.gov as NCT0148309.

Stable iron isotope studies in Rwandese women indicate that the common bean has limited potential as a vehicle for iron biofortification

Biofortification of plants is a new approach to combat iron deficiency. Common beans (Phaseolus vulgaris) can be bred with a higher iron concentration but are rich in iron absorption inhibitors, phytic acid (PA), and polyphenols (PP). To evaluate the potential of beans to combat iron deficiency, three iron absorption studies were carried out in 61 Rwandese women with low iron status. Studies 1 and 2 compared iron absorption from high and low PP beans, similar in PA and iron, fed as bean puree in a double meal design or with rice and potatoes as multiple meals. Study 3 compared iron absorption from high and normal iron beans with similar PP levels and a PA:iron molar ratio, fed with potatoes or rice in multiple meals. Iron absorption was measured as erythrocyte incorporation of stable iron isotopes. In study 1, iron absorption from the high PP bean (3.4%) was 27% lower (P < 0.01) than from low PP bean (4.7%), but when fed in multiple meals (study 2), there was no difference (7 and 7.4%, respectively; P > 0.05). In study 3, iron absorption from the high iron bean (3.8%) was 40% lower (P < 0.001) than from the normal iron bean (6.3%), resulting in equal amounts of iron absorbed. When beans were combined with other meal components in multiple meals, high PP concentration had no negative impact on iron absorption. However, the quantity of iron absorbed from composite meals with high iron beans was no higher than with normal iron beans, indicating that efficacious iron biofortification may be difficult to achieve in beans rich in PA and PP.

Iron and malaria: absorption, efficacy and safety

Febrile malaria and asymptomatic malaria parasitemia substantially decrease iron absorption in single-meal, stable isotope studies in women and children, but to date there is no evidence of decreased efficacy of iron-fortified foods in malaria-endemic regions. Without inadequate malarial surveillance or health care, giving iron supplements to children in areas of high transmission could increase morbidity and mortality. The most likely explanation is the appearance of non-transferrin-bound iron (NTBI) in the plasma. NTBI forms when the rate of iron influx into the plasma exceeds the rate of iron binding to transferrin. Two studies in women have reported substantially increased NTBI with the ingestion of iron supplements. Our studies confirm this, but found no significant increase in NTBI on consumption of iron-fortified food. It seems likely that the malarial parasite in hepatocytes can utilize NTBI, but it cannot do so in infected erythrocytes. NTBI however may increase the sequestration of parasite-infected erythrocytes in capillaries. Bacteremia is common in children with severe malaria and sequestration in villi capillaries could lead to a breaching of the intestinal barrier, allowing the passage of pathogenic bacteria into the systemic circulation. This is especially important as frequent high iron doses increase the number of pathogens in the intestine at the expense of the barrier bacteria.

Polyphenols and phytic acid contribute to the low iron bioavailability from common beans in young women

Low iron absorption from common beans might contribute to iron deficiency in countries where beans are a staple food. High levels of phytic acid (PA) and polyphenols (PP) inhibit iron absorption; however, the effect of bean PP on iron absorption in humans has not been demonstrated and, with respect to variety selection, the relative importance of PP and PA is unclear. To evaluate the influence of bean PP relative to PA on iron absorption in humans, 6 stable iron isotope absorption studies were conducted in women (16 or 17 per study). Bean PP (20, 50, and 200 mg) were added in studies 1-3 as red bean hulls to a bread meal. Studies 4- 6 investigated the influence on iron absorption of PP removal and dephytinization of whole red bean porridge and PP removal from dephytinized porridge. Iron absorption was lowered by 14% with 50 mg PP (P < 0.05) and by 45% with 200 mg PP (P < 0.001). The mean iron absorption from whole bean porridge was 2.5%. PP and PA removal increased absorption 2.6-fold (P < 0.001) and removal of PP from dephytinized porridge doubled absorption (P < 0.001). Between-study comparisons indicated that dephytinization did not increase iron absorption in the presence of PP, but in their absence, absorption increased 3.4-fold (P < 0.001). These data suggest that in countries where beans are a staple food, PP and PA concentrations should be considered when selecting bean varieties for human consumption. Lowering only one inhibitor will have a modest influence on iron absorption.

Iron bioavailability and dietary reference values

Iron differs from other minerals because iron balance in the human body is regulated by absorption only because there is no physiologic mechanism for excretion. On the basis of intake data and isotope studies, iron bioavailability has been estimated to be in the range of 14-18% for mixed diets and 5-12% for vegetarian diets in subjects with no iron stores, and these values have been used to generate dietary reference values for all population groups. Dietary factors that influence iron absorption, such as phytate, polyphenols, calcium, ascorbic acid, and muscle tissue, have been shown repeatedly to influence iron absorption in single-meal isotope studies, whereas in multimeal studies with a varied diet and multiple inhibitors and enhancers, the effect of single components has been, as expected, more modest. The importance of fortification iron and food additives such as erythorbic acid on iron bioavailability from a mixed diet needs clarification. The influence of vitamin A, carotenoids, and nondigestible carbohydrates on iron absorption and the nature of the "meat factor" remain unresolved. The iron status of the individual and other host factors, such as obesity, play a key role in iron bioavailability, and iron status generally has a greater effect than diet composition. It would therefore be timely to develop a range of iron bioavailability factors based not only on diet composition but also on subject characteristics, such as iron status and prevalence of obesity.

Revised Recommendations for Iron Fortification of Wheat Flour and an Evaluation of the Expected Impact of Current National Wheat Flour Fortification Programs

Background

Iron fortification of wheat flour is widely used as a strategy to combat iron deficiency.

Objective

To review recent efficacy studies and update the guidelines for the iron fortification of wheat flour.

Methods

Efficacy studies with a variety of iron-fortified foods were reviewed to determine the minimum daily amounts of additional iron that have been shown to meaningfully improve iron status in children, adolescents, and women of reproductive age. Recommendations were computed by determining the fortification levels needed to provide these additional quantities of iron each day in three different wheat flour consumption patterns. Current wheat flour iron fortification programs in 78 countries were evaluated.

Results

When average daily consumption of low-extraction (≤ 0.8% ash) wheat flour is 150 to 300 g, it is recommended to add 20 ppm iron as NaFeEDTA, or 30 ppm as dried ferrous sulfate or ferrous fumarate. If sensory changes or cost limits the use of these compounds, electrolytic iron at 60 ppm is the second choice. Corresponding fortification levels were calculated for wheat flour intakes of < 150 g/day and > 300 g/day. Electrolytic iron is not recommended for flour intakes of < 150 g/day. Encapsulated ferrous sulfate or fumarate can be added at the same concentrations as the non-encapsulated compounds. For high-extraction wheat flour (> 0.8% ash), NaFeEDTA is the only iron compound recommended. Only nine national programs (Argentina, Chile, Egypt, Iran, Jordan, Lebanon, Syria, Turkmenistan, and Uruguay) were judged likely to have a significant positive impact on iron status if coverage is optimized. Most countries use non-recommended, low-bioavailability, atomized, reduced or hydrogen-reduced iron powders.

Conclusion

Most current iron fortification programs are likely to be ineffective. Legislation needs updating in many countries so that flour is fortified with adequate levels of the recommended iron compounds.

Regular consumption of a complementary food fortified with ascorbic acid and ferrous fumarate or ferric pyrophosphate is as useful as ferrous sulfate in maintaining hemoglobin concentrations >105 g/L in young Bangladeshi children

BACKGROUND

Non-water-soluble iron compounds have been reported to be less well absorbed than ferrous sulfate in young children, and concern has been raised about their usefulness as food fortificants.

OBJECTIVE

The objective was to evaluate the usefulness of ferrous fumarate and ferric pyrophosphate, compared with ferrous sulfate, in maintaining hemoglobin concentrations >105 g/L in Bangladeshi children.

DESIGN

Two hundred thirty-five children aged 7-24 mo (hemoglobin >105 g/L) were randomly assigned in a double-blind study to receive an infant cereal fortified with ferrous fumarate, ferric pyrophosphate, or ferrous sulfate. One serving of cereal (9.3 mg Fe; molar ratio of ascorbic acid to iron of 3:1) was consumed per day, 6 d/wk, for 9 mo. Blood samples were drawn at 4.5 and 9 mo.

RESULTS

Raw data were reformatted, and a "time to event" was calculated that corresponded to reaching the following thresholds: hemoglobin <105 g/L, plasma ferritin <12 microg/L, or plasma C-reactive protein >10 mg/L at baseline, 4.5 mo, or 9 mo. Data were censored when children did not reach the threshold or were lost to follow-up. A Kaplan-Meier approach was used to compare the 3 groups. No statistically significant differences were observed for hemoglobin <105 g/L (P = 0.943), plasma ferritin <12 microg/L (P = 0.601), or plasma C-reactive protein >10 mg/L (P = 0.508).

CONCLUSIONS

Contrary to earlier concerns, these results do not indicate differences in usefulness between water-soluble and non-water-soluble iron compounds in maintaining hemoglobin concentrations and preventing iron deficiency. These data will be important in the development of food-fortification strategies to combat anemia and iron deficiency in highly vulnerable population groups.

[Conclusions and recommendations of a WHO expert consultation meeting on iron supplementation for infants and young children in malaria endemic areas]

This article presents the results of an expert consultation meeting aimed at evaluating the safety and public health implications of administering supplemental iron to infants and young children in malaria-endemic areas. Participants at this meeting that took place in Lyon, France on June 12-14, 2006 reached consensus on several important issues related to iron supplementation for infants and young children in malaria-endemic areas. The conclusions in this report apply specifically to regions where malaria is endemic.

Chili, but not turmeric, inhibits iron absorption in young women from an iron-fortified composite meal

Chili and turmeric are common spices in indigenous diets in tropical regions. Being rich in phenolic compounds, they would be expected to bind iron (Fe)(3) in the intestine and inhibit Fe absorption in humans. Three experiments were conducted in healthy young women (n = 10/study) to assess the effect of chili and turmeric on Fe absorption from a rice-based meal containing vegetables and iron fortified fish sauce in vivo. Iron absorption was determined by erythrocyte incorporation of stable isotope labels ((57)Fe/(58)Fe) using a randomized crossover design. Addition of freeze-dried chili (4.2 g dry powder, 25 mg polyphenols as gallic acid equivalents) reduced Fe absorption from the meal by 38% (6.0% with chili vs. 9.7% without chili, P = 0.0017). Turmeric (0.5 g dry powder, 50 mg polyphenols as gallic acid equivalents) did not inhibit iron absorption (P = 0.91). A possible effect of chili on gastric acid secretion was indirectly assessed by comparing Fe absorption from acid soluble [(57)Fe]-ferric pyrophosphate relative to water soluble [(58)Fe]-ferrous sulfate from the same meal in the presence and absence of chili. Chili did not enhance gastric acid secretion. Relative Fe bioavailability of ferric pyrophosphate was 5.4% in presence of chili and 6.4% in absence of chili (P = 0.47). Despite the much higher amount of phenolics in the turmeric meal, it did not affect iron absorption. We conclude that both phenol quality and quantity determine the inhibitory effect of phenolic compounds on iron absorption.

The Usefulness of in vitro Models to Predict the Bioavailability of Iron and Zinc: A Consensus Statement From the HarvestPlus Expert Consultation

A combination of dietary and host-related factors determines iron and zinc absorption, and several in vitro methods have been developed as preliminary screening tools for assessing bioavailability. An expert committee has reviewed evidence for their usefulness and reached a consensus. Dialyzability (with and without simulated digestion) gives some useful information but cannot predict the correct magnitude of response and may sometimes predict the wrong direction of response. Caco-2 cell systems (with and without simulated digestion) have been developed for iron availability, but the magnitude of different effects does not always agree with results obtained in human volunteers, and the data for zinc are too limited to draw conclusions about the validity of the method. Caco-2 methodologies vary significantly between laboratories and require experienced technicians and good quality cell culture facilities to obtain reproducible results. Algorithms can provide semi-quantitative information enabling diets to be classified as high, moderate, or low bioavailability. While in vitro methods can be used to generate ideas and develop hypotheses, they cannot be used alone for important decisions concerning food fortification policy, selection of varieties for plant breeding programs, or for new product development in the food industry. Ultimately human studies are required for such determinations.

Ascorbic acid supplementation and regular consumption of fresh orange juice increase the ascorbic acid content of human milk: studies in European and African lactating women

BACKGROUND

Little is known about the influence of an increased intake of ascorbic acid (AA) on human milk AA output.

OBJECTIVE

We aimed to compare human milk AA content in European and African women and to evaluate the influence of increased AA intake on human milk AA output.

DESIGN

Apparently healthy lactating women were recruited. AA was analyzed by titration with 2,6-dichlorophenol-indophenol.

RESULTS

Mean human milk AA was approximately 50% lower (P < 0.001) in the African women (31 mg/kg; n = 171) than in the European women (63 mg/kg; n = 142). AA supplementation (1000 mg/d for 10 d) increased mean human milk AA from 19 to 60 mg/kg (P < 0.001) and from 60 to 70 mg/kg (P = 0.03) in 18 African and 10 European women, respectively. In 11 African women, mean human milk AA increased from 17 to 36 mg/kg (P < 0.001) after intake of 100 mg AA/d for 10 d. In African women, intake of 1 serving of orange juice per week had no significant effect, whereas 3 or 5 servings/wk ( approximately 100 mg AA/serving) for 6 wk increased mean human milk AA from 16 to 32 mg/kg (n = 13) and from 21 to 46 mg/kg (n = 13), respectively (P < 0.001).

CONCLUSIONS

Human milk AA can be doubled or tripled by increased intake of AA in women with low human milk AA content at baseline. The response to a relatively high dose of AA was modest in European women in contrast with the 3-fold increase in mean human milk AA content in African women. These data indicate that human milk AA content is regulated.

Sodium iron EDTA [NaFe(III)EDTA] as a food fortificant: erythrocyte incorporation of iron and apparent absorption of zinc, copper, calcium, and magnesium from a complementary food based on wheat and soy in healthy infants

BACKGROUND

Phytic acid is a strong inhibitor of iron absorption from fortified foods. In adults, this inhibitory effect can be overcome by adding ascorbic acid with the iron fortificant or by using a "protected" iron compound such as NaFeEDTA. In addition, the use of NaFeEDTA as an iron fortificant has been reported to increase zinc absorption in adult women. No information is available on iron bioavailability from NaFeEDTA or the influence of NaFeEDTA on minerals and trace elements in infants.

OBJECTIVE

We aimed to compare iron bioavailability from a complementary food based on wheat and soy fortified with either NaFeEDTA or ferrous sulfate plus ascorbic acid. The apparent absorption of zinc, copper, calcium, and magnesium was evaluated in parallel.

DESIGN

Stable-isotope techniques were used in a crossover design to evaluate erythrocyte incorporation of iron 14 d after administration of labeled test meals and the apparent absorption of zinc, copper, calcium, and magnesium on the basis of fecal monitoring in 11 infants.

RESULTS

Geometric mean erythrocyte incorporation of iron was 3.7% (NaFeEDTA) and 4.9% (ferrous sulfate plus ascorbic acid) (P = 0.08). No significant differences in the apparent absorption of zinc, copper, calcium, or magnesium were observed between test meals (n = 10).

CONCLUSIONS

Iron bioavailability from a high-phytate, cereal-based complementary food fortified with either NaFeEDTA or ferrous sulfate plus ascorbic acid was not significantly different. NaFeEDTA did not influence the apparent absorption of zinc, copper, calcium, or magnesium. NaFeEDTA does not provide any nutritional benefit compared with the combination of a highly bioavailable iron compound and ascorbic acid.

Human milk as a source of ascorbic acid: no enhancing effect on iron bioavailability from a traditional complementary food consumed by Bangladeshi infants and young children

BACKGROUND

Iron bioavailability from traditional complementary foods based on cereals and legumes can be expected to be low unless ascorbic acid-rich foods are incorporated into the diet.

OBJECTIVE

We evaluated human milk as a source of ascorbic acid for enhancing iron bioavailability from khichuri, a complementary food based on rice and lentils.

DESIGN

Erythrocyte incorporation of stable iron isotopes 14 d after administration was used as a proxy for iron bioavailability. Children aged 8-18 mo (n = 31) were breastfed (32-90 mg ascorbic acid/kg human milk) immediately after intake of 4 servings of khichuri labeled with (57)Fe (test meal B) and were offered water after intake of 4 servings of khichuri labeled with (58)Fe (test meal A). Test meals were fed twice daily during 4 d in the order of AABBAABB or BBAABBAA.

RESULTS

The mean intakes of human milk and ascorbic acid were 274 g (range: 60-444 g) and 14 mg (range: 4-28 mg, respectively). The mean molar ratio of ascorbic acid to iron was 2.3 (range: 0.7-4.6). The geometric mean iron bioavailability from khichuri fed with or without human milk was 6.2% and 6.5%, respectively (P = 0.76, paired Student's t test).

CONCLUSIONS

Although human milk contributed significant quantities of ascorbic acid, no significant difference in iron bioavailability was found between khichuri consumed with water and that consumed with human milk. These results indicate either that the molar ratio of ascorbic acid to iron was not sufficiently high to overcome the inhibitory effect of phytic acid in khichuri (30 mg/serving) or that components of human milk modified the influence of ascorbic acid on iron bioavailability.

Dephytinization of a complementary food based on wheat and soy increases zinc, but not copper, apparent absorption in adults

Complementary foods based on cereals may contain high amounts of phytic acid, which binds strongly to minerals and trace elements. The objective of the study was to evaluate the effect of dephytinization of a cereal-based complementary food on zinc and copper apparent absorption in adults. A dephytinized complementary food (<0.03 mg phytic acid/g) and one containing the native phytic acid concentration (4 mg/g) were labeled extrinsically with stable isotopes ((70)Zn and (65)Cu). Apparent zinc and copper absorption was based on fecal excretion of nonabsorbed labels in 9 adults, using a crossover design. Stable isotopes were quantified by thermal ionization MS. Apparent fractional zinc absorption was significantly higher (P = 0.005; Student's paired t test) from the dephytinized complementary food (34.6 +/- 8.0%; mean +/- SD) than from the complementary food with native phytic acid concentration (22.8 +/- 8.8%). Apparent fractional copper absorption did not differ (P = 0.167; 19.7 +/- 5.1% dephytinized vs. 23.7 +/- 8.1% native phytic acid). These results clearly demonstrate the beneficial effect of dephytinization of a complementary food on fractional absorption of zinc but not of copper in adults. The long-term nutritional benefits of dephytinization of complementary foods should be evaluated in young children.

The effect of retinyl palmitate added to iron-fortified maize porridge on erythrocyte incorporation of iron in African children with vitamin A deficiency

Retinyl palmitate added to Fe-fortified maize bread has been reported to enhance Fe absorption in adult Venezuelan subjects but not in Western Europeans. It is not known to what extent these results were influenced by differences in vitamin A status of the study subjects. The objective of the present study was to evaluate the influence of retinyl palmitate added to Fe-fortified maize porridge on erythrocyte incorporation of Fe in children with vitamin A deficiency, before and after vitamin A supplementation. Erythrocyte incorporation of Fe-stable isotopes was measured 14 d after intake of maize porridge (2.0 mg Fe added as ferrous sulfate) with and without added retinyl palmitate (3.5 micromol; 3300 IU). The study was repeated 3 weeks after vitamin A supplementation (intake of a single dose of 210 micromol retinyl palmitate; 'vitamin A capsule'). Vitamin A status was evaluated by the modified relative dose-response (MRDR) technique. Retinyl palmitate added to the test meal reduced the geometric mean erythrocyte incorporation of Fe at baseline from 4.0 to 2.6 % (P=0.008, n 13; paired t test). At 3 weeks after vitamin A supplementation, geometric mean erythrocyte incorporation was 1.9 and 2.3 % respectively from the test meal with and without added retinyl palmitate (P=0.283). Mean dehydroretinol:retinol molar ratios were 0.156 and 0.125 before and after intake of the single dose of 210 micromol retinyl palmitate; 'vitamin A capsule' (P=0.15). In conclusion, retinyl palmitate added to the labelled test meals significantly decreased erythrocyte incorporation of Fe in children with vitamin A deficiency at baseline but had no statistically significant effect 3 weeks after vitamin A supplementation. The difference in response to retinyl palmitate added to Fe-fortified maize porridge on erythrocyte incorporation of Fe before and after intake of the vitamin A capsule indicates, indirectly, changes in vitamin A status not measurable by the MRDR technique. The lack of conclusive data on the effect of retinyl palmitate on Fe absorption indicates the complexity of the interactions between vitamin A status, dietary vitamin A and Fe metabolism.

The usefulness of elemental iron for cereal flour fortification: a SUSTAIN Task Force report. Sharing United States Technology to Aid in the Improvement of Nutrition

Fortification of cereal flours may be a useful public health strategy to combat iron deficiency. Cereal flours that are used shortly after production (e.g., baking flour) can be fortified with soluble iron compounds, such as ferrous sulfate, whereas the majority of flours stored for longer periods is usually fortified with elemental iron powders to avoid unacceptable sensory changes. Elemental iron powders are less well absorbed than soluble iron compounds and they vary widely in their absorption depending on manufacturing method and physicochemical characteristics. Costs vary with powder type, but elemental iron powders are generally less expensive than ferrous sulfate. This review evaluates the usefulness of the different elemental iron powders based on results from in vitro studies, rat assays, human bioavailability studies, and efficacy studies monitoring iron status in human subjects. It concludes that, at the present time, only electrolytic iron powder can be recommended as an iron fortificant. Because it is only approximately half as well absorbed as ferrous sulfate, it should be added to provide double the amount of iron.

Fighting iron deficiency anemia with iron-rich rice

OBJECTIVE

Iron deficiency is estimated to affect about 30% of the world population. Iron supplementation in the form of tablets and food fortification has not been successful in developing countries, and iron deficiency is still the most important deficiency related to malnutrition. Here we present experiments that aim to increase the iron content in rice endosperm and to improve its absorption in the human intestine by means of genetic engineering.

METHODS

We first introduced a ferritin gene from Phaseolus vulgaris into rice grains, increasing their iron content up to twofold. To increase iron bioavailability, we introduced a thermo-tolerant phytase from Aspergillus fumigatus into the rice endosperm. In addition, as cysteine peptides are considered major enhancers of iron absorption, we over-expressed the endogenous cysteine-rich metallothionein-like protein.

RESULTS

The content of cysteine residues increased about sevenfold and the phytase level in the grains about one hundred and thirtyfold, giving a phytase activity sufficient to completely degrade phytic acid in a simulated digestion experiment.

CONCLUSIONS

This rice, with higher iron content, rich in phytase and cysteine-peptide has a great potential to substantially improve iron nutrition in those populations where iron deficiency is so widely spread.

Improving iron absorption from a Peruvian school breakfast meal by adding ascorbic acid or Na2EDTA

BACKGROUND

Iron-fortified school breakfasts have been introduced in Peru to combat childhood iron deficiency.

OBJECTIVE

We evaluated whether iron absorption from a school breakfast meal was improved by increasing the ascorbic acid content or by adding an alternative enhancer of iron absorption, Na2EDTA.

DESIGN

In a crossover design, iron absorption from test meals was evaluated by erythrocyte incorporation of 58Fe and 57Fe. The test meals (wheat bread and a drink containing cereal, milk, and soy) contained 14 mg added Fe (as ferrous sulfate) including 2.0-2.6 mg 58Fe or 4.0-7.0 mg 57Fe.

RESULTS

Geometric mean iron absorption increased significantly from 5.1% to 8.2% after the molar ratio of ascorbic acid to fortification iron was increased from 0.6:1 to 1.6:1 (P < 0.01; n = 9). Geometric mean iron absorption increased significantly from 2.9% to 3.8%, from 2.2% to 3.5%, and from 2.4% to 3.7% after addition of Na2EDTA at molar ratios relative to fortification iron of 0.3:1, 0.7:1, and 1:1, respectively, compared with test meals containing no added enhancers (P < 0.01; n = 10 for all). Iron absorption after addition of ascorbic acid (molar ratio 0.6:1) was not significantly different from that after addition of Na2EDTA (molar ratio 0.7:1).

CONCLUSIONS

Ascorbic acid and Na2EDTA did not differ significantly in their enhancing effects on iron absorption at molar ratios of 0.6:1 to 0.7:1 relative to fortification iron. Additional ascorbic acid (molar ratio 1.6:1) increased iron absorption significantly. Increasing the molar ratio of Na2EDTA to fortification iron from 0.3:1 to 1:1 had no effect on iron absorption.

Low dose oral iodized oil for control of iodine deficiency in children

In areas where iodized salt is not available, oral iodized oil is often used to correct I deficiency despite a lack of consensus on the optimal dose or duration of effect, particularly in children, a main target group. Annual doses ranging from 400 to 1000 mg have been advocated for school-age children. Because lower doses of iodized oil have been shown to be effective in treating I deficiency in adults, the aim of this study was to evaluate the efficacy and safety of a low dose of oral iodized oil in goitrous I-deficient children. Goitrous children (n 104, mean age 8.4 years, range 6-12 years, 47% female) received 0.4 ml oral iodized poppyseed-oil containing 200 mg I. Baseline measurements included I in spot urines (UI), serum thyroxine (T4), whole blood thyroid-stimulating hormone (TSH), and thyroid-gland volume using ultrasound. At 1, 5, 10, 15, 30 and 50 weeks post-intervention, UI, TSH and T4 were measured. At 10, 15, 30 and 50 weeks, thyroid-gland volume was remeasured. At 30 and 50 weeks the mean percentage change in thyroid volume from baseline was -35% and -41% respectively. The goitre rate fell to 38% at 30 weeks and 17% at 50 weeks. No child showed signs of I-induced hypo- or hyperthyroidism. UI remained significantly increased above baseline for the entire year (P < 0.001); the median UI at 50 weeks was 97 micrograms/l, at the World Health Organization cut-off value (100 micrograms/l) for I-deficiency disorders risk. In this group of goitrous children, an oral dose of 200 mg I as Lipiodol (Guerbert, Roissy CdG Cedex, France) was safe and effective for treating goitre and maintaining normal I status for at least 1 year.

Iron supplementation in goitrous, iron-deficient children improves their response to oral iodized oil

OBJECTIVE

In developing countries, many children are at high risk for both goiter and iron-deficiency anemia. Because iron deficiency may impair thyroid metabolism, the aim of this study was to determine if iron supplementation improves the response to oral iodine in goitrous, iron-deficient anemic children.

DESIGN

A trial of oral iodized oil followed by oral iron supplementation in an area of endemic goiter in the western Ivory Coast.

METHODS

Goitrous, iodine-deficient children (aged 6-12 years; n=109) were divided into two groups: Group 1 consisted of goitrous children who were not anemic; Group 2 consisted of goitrous children who were iron-deficient anemic. Both groups were given 200mg oral iodine as iodized oil. Thyroid gland volume using ultrasound, urinary iodine concentration (UI), serum thyroxine (T(4)) and whole blood TSH were measured at baseline, and at 1, 5, 10, 15 and 30 weeks post intervention. Beginning at 30 weeks, the anemic group was given 60mg oral iron as ferrous sulfate four times/week for 12 weeks. At 50 and 65 weeks after oral iodine (8 and 23 weeks after completing iron supplementation), UI, TSH, T(4) and thyroid volume were remeasured.

RESULTS

The prevalence of goiter at 30 weeks after oral iodine in Groups 1 and 2 was 12% and 64% respectively. Mean percent change in thyroid volume compared with baseline at 30 weeks in Groups 1 and 2 was -45.1% and -21.8% respectively (P<0.001 between groups). After iron supplementation in Group 2, there was a further decrease in mean thyroid volume from baseline in the anemic children (-34.8% and -38.4% at 50 and 65 weeks) and goiter prevalence fell to 31% and 20% at 50 and 65 weeks.

CONCLUSION

Iron supplementation may improve the efficacy of oral iodized oil in goitrous children with iron-deficiency anemia.

Persistence of goiter despite oral iodine supplementation in goitrous children with iron deficiency anemia in Côte d'Ivoire

BACKGROUND

In developing countries, many children are at high risk of goiter and iron deficiency anemia. Because iron deficiency can have adverse effects on thyroid metabolism, iron deficiency may influence the response to supplemental iodine in areas of endemic goiter.

OBJECTIVE

The aim of this study was to determine whether goitrous children with iron deficiency anemia would respond to oral iodine supplementation.

DESIGN

A trial of oral iodine supplementation was carried out in an area of endemic goiter in western Côte d'Ivoire in goitrous children (n = 109) aged 6-12 y. Group 1 (n = 53) consisted of goitrous children who were not anemic. Group 2 (n = 56) consisted of goitrous children who had iron deficiency anemia. At baseline, thyroid gland volume and urinary iodine, thyrotropin, and thyroxine were measured by using ultrasound. Each child received 200 mg I orally and was observed for 30 wk, during which urinary iodine, thyrotropin, thyroxine, hemoglobin, and thyroid gland volume were measured.

RESULTS

The prevalence of goiter at 30 wk was 12% in group 1 and 64% in group 2. The mean percentage change from baseline in thyroid volume 30 wk after administration of oral iodine was -45.1% in group 1 and -21.8% in group 2 (P < 0.001). Among the anemic children, there was a strong correlation between the percentage decrease in thyroid volume and hemoglobin concentration (r(2) = 0.65).

CONCLUSION

The therapeutic response to oral iodine was impaired in goitrous children with iron deficiency anemia, suggesting that the presence of iron deficiency anemia in children limits the effectiveness of iodine intervention programs.

Effects of foods rich in polyphenols on nitrogen excretion in rats

The extent to which tea, cocoa and carob (foods rich in polyphenols) influence fecal nitrogen (N) excretion was investigated in rats. The studies took into account the methylxanthine contents of tea and cocoa as well as the poor digestibility of cocoa nitrogen. Balance measurements indicated that all three food sources significantly increased fecal nitrogen excretion relative to methylxanthine-matched control diets (p less than 0.01). In the case of cocoa, virtually all the increase could be attributed to the poor digestibility of cocoa protein itself (estimated to be only 28-30% of total N in cocoa powder). There appeared to be no other effects. With extracts of tea and carob, however, the increased excretion of N in feces resulted either from a decreased digestibility of other dietary protein, through interaction with their polyphenols, or from a stimulation of the excretion of endogenous (body) nitrogen. With respect to the latter possibility, a preliminary investigation with the stable isotope of nitrogen (15N) showed that tea produced a marked increase in the excretion of endogenous nitrogen. These studies, therefore, indicate that foods rich in polyphenols have varying effects on N excretion in feces and that, in the case of tea at least, the loss of endogenous nitrogen may be a major contributing factor.