Iron deficiency in infancy: applying a physiologic framework for prediction.

BACKGROUND: Infants aged 6-24 mo are at high risk of iron deficiency. Numerous studies worldwide have sought to identify predictors of iron deficiency in this age group. OBJECTIVE: The objectives of the study were to apply a physiologic model to identify risk factors for iron deficiency and to consider those risk factors under different conditions of iron supplementation. We predicted that factors related to iron status at birth (lower gestational age and lower birth weight), postnatal needs for iron (more rapid growth), and bioavailable iron (more cow milk) would be major risk factors. DESIGN: The physiologic framework was assessed in 1657 Chilean infants (aged 12 mo) with birth weights >or=3 kg who were randomly assigned at age 6 mo to high or low iron supplementation or no added iron. Based on venous blood, the analysis used mean corpuscular volume and concentrations of hemoglobin, free erythrocyte protoporphyrin, and ferritin. Logistic regression models were used to identify predictors of iron deficiency anemia and iron deficiency without anemia. RESULTS: The prevalence of iron deficiency (>or=2 abnormal iron measures) was 34.9% at age 12 mo. Of 186 infants with hemoglobin concentrations <110 g/L, 158 (84.9%) were iron deficient. The only consistent (and the strongest) predictor of iron deficiency or iron deficiency anemia was lower 6-mo hemoglobin. Factors related to poorer iron status at birth (lower birth weight, shorter gestation though full-term, or both) were predictors in the no-added-iron and high-iron groups. Otherwise, predictors varied by iron supplementation. CONCLUSION: Variations in predictors of iron deficiency or iron deficiency anemia according to iron supplementation suggest that direct comparisons across studies are tenuous at best without data on early iron status and certainty that specific conditions are comparable.

Iron bioavailability in corn-masa tortillas is improved by the addition of disodium EDTA.

Corn-masa flour flat bread tortillas are the main staple of Mexican and Central American populations. Due to high concentrations of inhibitors of iron absorption, the bioavailability from this matrix is unknown. We wanted to determine the most suitable fortificant that would efficaciously improve iron bioavailability. In tortillas prepared with commercial precooked, lime-treated, corn-masa flour, we examined the in vitro solubility of the following forms of iron: native iron with and without Na2EDTA, elemental reduced iron plus Na2EDTA, ferrous fumarate with and without Na2EDTA, bisglycine iron, ferrous sulfate and NaFeEDTA. We also examined the in vivo bioavailability in humans with double radioiron erythrocyte incorporation of ferrous fumarate with and without Na2EDTA, bisglycine iron, NaFeEDTA and native iron plus Na2EDTA, beans and rice. In vitro, solubility ranged from 1% in iron forms without Na2EDTA to 19.4% for NaFeEDTA. Forms of iron with Na2EDTA had intermediate values. In vivo radioiron studies showed that iron forms without Na2EDTA also had low bioavailability (< or =1%). NaFeEDTA had the highest bioavailability (5.3%). The bioavailability of all iron forms improved significantly when tested with Na2EDTA (<0.05). Adding Na2EDTA to ferrous fumarate increased bioavailability from 0.87% to 2.9% (P < 0.001). We conclude that NaFeEDTA is the form of iron best absorbed, but alternatively, ferrous fumarate plus Na2EDTA comprises a feasible option as a fortificant.

Behavioral and developmental effects of preventing iron-deficiency anemia in healthy full-term infants.

OBJECTIVE: To determine the behavioral and developmental effects of preventing iron-deficiency anemia in infancy. METHODS: Healthy full-term Chilean infants who were free of iron-deficiency anemia at 6 months were assigned to high- or low-iron groups or to high- or no-added-iron groups. Behavioral/developmental outcomes at 12 months of age included overall mental and motor test scores and specific measures of motor functioning, cognitive processing, and behavior. There were no differences between high- and low-iron groups in the prevalence of iron-deficiency anemia or behavioral/developmental outcome, and they were combined to form an iron-supplemented group (n = 1123) for comparison with the no-added-iron group (n = 534). RESULTS: At 12 months, iron-deficiency anemia was present in 3.1% and 22.6% of the supplemented and unsupplemented groups, respectively. The groups differed in specific behavioral/developmental outcomes but not on global test scores. Infants who did not receive supplemental iron processed information slower. They were less likely to show positive affect, interact socially, or check their caregivers' reactions. A smaller proportion of them resisted giving up toys and test materials, and more could not be soothed by words or objects when upset. They crawled somewhat later and were more likely to be tremulous. CONCLUSIONS: The results suggest that unsupplemented infants responded less positively to the physical and social environment. The observed differences seem to be congruent with current understanding of the effects of iron deficiency on the developing brain. The study shows that healthy full-term infants may receive developmental and behavioral benefits from iron supplementation in the first year of life.

Multiple-micronutrient fortification technology development and evaluation: from lab to market.

At the World Summit for Children (New York, 1990), a resolution was passed to eliminate vitamin A and iodine deficiencies and significantly reduce iron-deficiency anemia by the year 2000. In responding to this urgent call, we developed a unique multiple-micronutrient fortification delivery system called "GrowthPlus/CreciPlus." Using this technology, a fortified powder fruit drink has been formulated and extensively evaluated. One serving of the product delivers the following US recommended dietary allowances: 20-30% of iron; 10-35% of vitamin A; 25-35% of iodine; 100-120% of vitamin C; 25-35% of zinc; 15-35% of folate; and 10-50% of vitamins E, B2, B6, and B12. This was accomplished through (a) identifying and selecting the right fortificants, and (b) understanding their chemical and physical properties that contribute to multiple problems (product acceptability, stability, and bioavailability). Data from a home-use test showed fortification with the "Multiple-Fortification Technology" has no effect on the appearance and taste of the eventually consumed powder fruit drink. One-year stability studies demonstrated that iodine and the vitamins have adequate stability. Bioavailability evaluation by using double-isotope labeling technique showed that the iron from the fortified powder drink has excellent bioavailability (23.4% +/- 6.7). In conclusion, a powder fruit drink has been clinically demonstrated to deliver multiple micronutrients, which include adequate levels of bioavailable iron, vitamin A, iodine, zinc, vitamin C, and B vitamins, without compromising taste, appearance, and bioavailability. The critical limiting step in the micronutrient fortification program is the production and distribution of the multiple-micronutrient-fortified product. The fortified powder drink was marketed in Venezuela under the brand name NutriStar.

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.

Factores que modifican el estado de nutrición de hierro: contenido de taninos de infusiones de hierbas / Factors that may influence nutritional iron status: Tannins in herbal infusions

Los taninos son compuestos naturales que se encuentran abundantemente en hierbas, maderas y frutas. Debido a sus numerosos radicalos hidroxilos se unen fuertemente a metales como Fe,Cu y Zn, propiedad que les confiere la capacidad de ser fuertes inhbidores de la absorción gastrointestinal de estos minerales. El propósito de este trabajo fue determinar el contenido de taninos presente en infusiones de hierbas habitualmente consumidas en Chile y otros países sudamericanos. La determinación de taninos se realizó a partir de infusiones preparadas con hierbas desecadas mediante la técnica de Folin Denis. La yerba mate, el té y el oréganos resultaron ser las hierbas con mayor contenido de taninos (117, 100 y 84 mg ácido tánico/g de muestra seca). Niveles intermedios la coca, el matico, el boldo, el palto, el laurel, el naranjo y el hinojo entre 20 y 40 mg de ácido tánico/g). El paico, el cedrón, el apio y la manzanilla contienen los niveles más bajos de taninos (<10 mg/g). Se concluye que las infusiones de hierba consumidas más frecuentemente con las comidas las concentraciones de taninos más altas, lo que podría estar influyendo en la biodisponibilidad del hierro de la dieta

Hemoglobin-fortified biscuits: bioavailability and its effect on iron nutriture in school children

En Chile, los escolares reciben diariamente 30g de galletas de harina de trigo en un Programa de Desayunos Escolares. Estas galletas fueron fortificadas con 6% de hemoglobulina de vacuno. La biodisponibilidad del hiero, determinada mediante una técnica dobleisotópica, mostró una elevada absorción del hierro hemínico en las galletas fortificadas (19.7%). En un estudio piloto, aun grupo de 215 escolares se les administró diariamente la galleta fortificada (30g) durante dos períodos escolares, comparando-se sus estrado nutricional férrico con 212 niños que recibieron galletas no fortificadas. Las aceptabilidad de la galleta fortificada fue excelente. Al inicio ambos grupos presentaron una nutrición de hierro comparablemente buena. Al término del primer y segundo período escolar, el grupo fortificado acusó promedios de ferritina sérica más elevados. Los depósitos de hierro eran suficientes (ferritina sérica > ou = 20 µg/lt) en el 92 y n79% de los sujetos fortificados, y controles, respectivamente (P < 0.004). La alta biodisponibilidad del hierro de esta galleta, sus óptimas condiciones organolépticas y su efecto sobre la nutrición de hierro, hacen de este producto una alternativa promisoria para la prevención de la deficiencia de hierro