Inhibition of iron absorption by calcium is modest in an iron-fortified, casein- and whey-based drink in Indian children and is easily compensated for by addition of ascorbic acid

Malnutrition and Allergies: Tipping the Immune Balance towards Health

Malnutrition, which includes macro- and micronutrient deficiencies, is common in individuals with allergic dermatitis, food allergies, rhinitis, and asthma. Prolonged deficiencies of proteins, minerals, and vitamins promote Th2 inflammation, setting the stage for allergic sensitization. Consequently, malnutrition, which includes micronutrient deficiencies, fosters the development of allergies, while an adequate supply of micronutrients promotes immune cells with regulatory and tolerogenic phenotypes. As protein and micronutrient deficiencies mimic an infection, the body's innate response limits access to these nutrients by reducing their dietary absorption. This review highlights our current understanding of the physiological functions of allergenic proteins, iron, and vitamin A, particularly regarding their reduced bioavailability under inflamed conditions, necessitating different dietary approaches to improve their absorption. Additionally, the role of most allergens as nutrient binders and their involvement in nutritional immunity will be briefly summarized. Their ability to bind nutrients and their close association with immune cells can trigger exaggerated immune responses and allergies in individuals with deficiencies. However, in nutrient-rich conditions, these allergens can also provide nutrients to immune cells and promote health.

Nutrition in chronic inflammatory conditions: Bypassing the mucosal block for micronutrients

Nutritional Immunity is one of the most ancient innate immune responses, during which the body can restrict nutrients availability to pathogens and restricts their uptake by the gut mucosa (mucosal block). Though this can be a beneficial strategy during infection, it also is associated with non-communicable diseases-where the pathogen is missing; leading to increased morbidity and mortality as micronutritional uptake and distribution in the body is hindered. Here, we discuss the acute immune response in respect to nutrients, the opposing nutritional demands of regulatory and inflammatory cells and particularly focus on some nutrients linked with inflammation such as iron, vitamins A, Bs, C, and other antioxidants. We propose that while the absorption of certain micronutrients is hindered during inflammation, the dietary lymph path remains available. As such, several clinical trials investigated the role of the lymphatic system during protein absorption, following a ketogenic diet and an increased intake of antioxidants, vitamins, and minerals, in reducing inflammation and ameliorating disease.

Factors affecting iron absorption and the role of fortification in enhancing iron levels

Iron is an important micronutrient required for a number of biological processes including oxygen transport, cellular respiration, the synthesis of nucleic acids and the activity of key enzymes. The World Health Organization has recognised iron deficiency as the most common nutritional deficiency globally and as a major determinant of anaemia. Iron deficiency anaemia affects 40% of all children between the ages of 6 and 59 months, 37% of mothers who are pregnant and 30% of women between the ages of 15 and 49 years worldwide. Dietary iron exists in two main forms known as haem iron and non-haem iron. Haem iron is obtained from animal sources such as meat and shows higher bioavailability than non-haem iron, which can be obtained from both plant and animal sources. Different components in food can enhance or inhibit iron absorption from the diet. Components such as meat proteins and organic acids increase iron absorption, while phytate, calcium and polyphenols reduce iron absorption. Iron levels in the body are tightly regulated since both iron overload and iron deficiency can exert harmful effects on human health. Iron is stored mainly as haemoglobin and as iron bound to proteins such as ferritin and hemosiderin. Iron deficiency affects individuals at increased risk due to factors such as age, pregnancy, menstruation and various diseases. Different solutions for iron deficiency are applied at individual and community levels. Iron supplements and intravenous iron can be used to treat individuals with iron deficiency, while various types of iron-fortified foods and biofortified crops can be employed for larger communities. Foods such as rice, flour and biscuits have been used to prepare fortified iron products. However, it is important to ensure the fortification process does not exert significant negative effects on organoleptic properties and the shelf life of the food product.

The IRONy in Athletic Performance

Iron is an essential micronutrient for athletes, intricately linked to their performance, by regulating cellular respiration and metabolism. Impaired iron levels in the body can significantly hinder athletic performance. The increased demand for iron due to exercise, coupled with potential dietary iron insufficiencies, particularly among endurance athletes, amplifies the risk of iron deficiency. Moreover, prolonged exercise can impact iron absorption, utilization, storage, and overall iron concentrations in an athlete. On the contrary, iron overload may initially lead to enhanced performance; however, chronic excess iron intake or underlying genetic conditions can lead to detrimental health consequences and may negatively impact athletic performance. Excess iron induces oxidative damage, not only compromising muscle function and recovery, but also affecting various tissues and organs in the body. This narrative review delineates the complex relationship between exercise and iron metabolism, and its profound effects on athletic performance. The article also provides guidance on managing iron intake through dietary adjustments, oral iron supplementation for performance enhancement in cases of deficiency, and strategies for addressing iron overload in athletes. Current research is focused on augmenting iron absorption by standardizing the route of administration while minimizing side effects. Additionally, there is ongoing work to identify inhibitors and activators that affect iron absorption, aiming to optimize the body's iron levels from dietary sources, supplements, and chelators. In summary, by refining the athletic diet, considering the timing and dosage of iron supplements for deficiency, and implementing chelation therapies for iron overload, we can effectively enhance athletic performance and overall well-being.

Calcium is a noncompetitive inhibitor of DMT1 on the intestinal iron absorption process: empirical evidence and mathematical modeling analysis

Iron absorption is a complex and highly controlled process where DMT1 transports nonheme iron through the brush-border membrane of enterocytes to the cytoplasm but does not transport alkaline-earth metals such as calcium. However, it has been proposed that high concentrations of calcium in the diet could reduce iron bioavailability. In this work, we investigate the effect of intracellular and extracellular calcium on iron uptake by Caco-2 cells, as determined by calcein fluorescence quenching. We found that extracellular calcium inhibits iron uptake by Caco-2 cells in a concentration-dependent manner. Chelation of intracellular calcium with BAPTA did not affect iron uptake, which indicates that the inhibitory effect of calcium is not exerted through intracellular calcium signaling. Kinetic studies performed, provided evidence that calcium acts as a reversible noncompetitive inhibitor of the iron transport activity of DMT1. Based on these experimental results, a mathematical model was developed that considers the dynamics of noncompetitive inhibition using a four-state mechanism to describe the inhibitory effect of calcium on the DMT1 iron transport process in intestinal cells. The model accurately predicts the calcein fluorescence quenching dynamics observed experimentally after an iron challenge. Therefore, the proposed model structure is capable of representing the inhibitory effect of extracellular calcium on DMT1-mediated iron entry into the cLIP of Caco-2 cells. Considering the range of calcium concentrations that can inhibit iron uptake, the possible inhibition of dietary calcium on intestinal iron uptake is discussed.

Synergistic Antifungal Effect of a Combination of Iron Deficiency and Calcium Supplementation

Fungal diseases have become a major public health issue worldwide. Increasing drug resistance and the limited number of available antifungals result in high morbidity and mortality. Metal-based drugs have been reported to be therapeutic agents against major protozoan diseases, but knowledge of their ability to function as antifungals is limited. In this study, we found that calcium supplementation combined with iron deficiency causes dramatic growth inhibition of the human fungal pathogens Aspergillus fumigatus, Candida albicans, and Cryptococcus neoformans. Calcium induces the downregulation of iron uptake-related genes and, in particular, causes a decrease in the expression of the transcription factor HapX, which tends to transcriptionally activate siderophore-mediated iron acquisition under iron-deficient conditions. Iron deficiency causes calcium overload and the overproduction of intracellular reactive oxygen species (ROS), and perturbed ion homeostasis suppresses fungal growth. These phenomena are consistently identified in azole-resistant A. fumigatus isolates. The findings here imply that low iron availability lets cells mistakenly absorb calcium as a substitute, causing calcium abnormalities. Thus, there is a mutual effect between iron and calcium in fungal pathogens, and the combination of calcium with an iron chelator could serve to improve antifungal therapy. IMPORTANCE Millions of immunocompromised people are at a higher risk of developing different types of severe fungal diseases. The limited number of antifungals and the emergence of antimicrobial resistance highlight an urgent need for new strategies against invasive fungal infections. Here, we report that calcium can interfere with iron absorption of fungal pathogens, especially in iron-limited environments. Thus, a combination of calcium supplementation with an iron chelator inhibits the growth of human fungal pathogens, including Aspergillus fumigatus, Candida albicans, and Cryptococcus neoformans. Moreover, we demonstrate that iron deficiency induces a nonspecific calcium uptake response, which results in toxic levels of metal. Findings in this study suggest that a microenvironment with excess calcium and limited iron is an efficient strategy to curb the growth of fungal pathogens, especially for drug-resistant isolates.

Iron Absorption: Factors, Limitations, and Improvement Methods

Iron is an essential element for human life since it participates in many functions in the human body, including oxygen transport, immunity, cell division and differentiation, and energy metabolism. Iron homeostasis is mainly controlled by intestinal absorption because iron does not have active excretory mechanisms for humans. Thus, efficient intestinal iron bioavailability is essential to reduce the risk of iron deficiency anemia. There are two forms of iron, heme and nonheme, found in foods. The average daily dietary iron intake is 10 to 15 mg in humans since only 1 to 2 mg is absorbed through the intestinal system. Nutrient-nutrient interactions may play a role in dietary intestinal iron absorption. Dietary inhibitors such as calcium, phytates, polyphenols and enhancers such as ascorbic acid and proteins mainly influence iron bioavailability. Numerous studies have been carried out for years to enhance iron bioavailability and combat iron deficiency. In addition to traditional methods, innovative techniques are being developed day by day to enhance iron bioavailability. This review will provide information about iron bioavailability, factors affecting absorption, iron deficiency, and recent studies on improving iron bioavailability.

Iron Bioavailability from Ferrous Ammonium Phosphate, Ferrous Sulfate, and Ferric Pyrophosphate in an Instant Milk Drink-A Stable Isotope Study in Children

Ferrous ammonium phosphate (FAP) is an iron salt that has been developed for the fortification of food matrices sensitive to color and flavor changes. The objective of the study was to measure iron absorption from FAP in young children and compare it to a previous evaluation of FAP in young women. A double-blind randomized crossover study with two parallel arms was used to evaluate the iron absorption from FAP added to reconstituted milk powder in comparison to that from ferrous sulfate (FeSO4) and ferric pyrophosphate (FePP). Iron absorption was measured in 39 children aged 3- to 6-years-old using erythrocyte incorporation of stable Fe isotopes (57Fe, 58Fe). The geometric mean iron absorption in iron replete children from FAP, FeSO4 and FePP from milk was 8.3%, 7.6% and 2.1%, respectively. Iron absorption from FAP and FeSO4 fortified milk was not significantly different (p = 0.199); however, it was significantly higher than from FePP fortified milk (p < 0.001). Iron bioavailability from FAP and FePP relative to FeSO4 (relative bioavailability (RBV)) was 110% and 33%, respectively. The RBV of FAP (110%) in iron replete children was higher than previously reported RBV (71%) in mainly iron deficient women. The difference in iron status between the children and women in the respective studies may explain the different RBV values and is discussed.

Plant-Based Dietary Practices and Socioeconomic Factors That Influence Anemia in India

While rates of malnutrition have declined over the last decade in India due to successful government interventions, the prevalence of anemia remains high. Staple foods provide almost 70% of the daily iron intake. As staple foods are a rich source of phytate, this ingested iron is poorly absorbed. Currently, 59% of children below 3 years of age, 50% of expectant mothers and 53% of women aged 15-19 years are anemic. The most common intervention strategy has been through the use of iron supplements. While the compliance has been low and supplies irregular, such high rates of anemia cannot be explained by iron deficiency alone. This review attempts to fit dietary and cooking practices, field-level diagnostics, cultural beliefs and constraints in implementation of management strategies into a larger picture scenario to offer insights as to why anemia continues to plague India. Since the rural Indian diet is predominantly vegetarian, we also review dietary factors that influence non-heme iron absorption. As a reference point, we also contrast anemia-related trends in India to the U.S.A. Thus, this review is an effort to convey a holistic evaluation while providing approaches to address this public health crisis.

Calcium Intake and Iron Status in Human Studies: A Systematic Review and Dose-Response Meta-Analysis of Randomized Trials and Crossover Studies

BACKGROUND

The interaction between dietary (and supplementary) divalent ions has been a long-standing issue in human nutrition research. Developing an optimal calcium and iron supplementation recommendation requires detailed knowledge of the potential trade-offs between: 1) the clinical effects of concurrent intake on iron absorption and hematological indices; and 2) the potentially negative effects of separated ingestion on adherence to iron and/or calcium supplements. Human clinical studies have examined the effects of calcium intake on iron status, but there are no meta-analyses or recent reviews summarizing the findings.

OBJECTIVES

To synthesize peer-reviewed, human, randomized, and cross-over studies on effects of calcium consumption on iron indices without age, gender, or any other restrictions.

METHODS

Weighted mean differences for total, heme, and nonheme iron absorption (%) and serum ferritin (μg/L) were obtained from pooled analysis of the highest daily calcium intake compared to the lowest daily calcium intake.

RESULTS

The negative effect of calcium intake was statistically significant in short-term iron absorption studies, but the effect magnitude was low [weighted mean difference (WMD) = -5.57%; 95% CI: -7.09 to -4.04]. The effect of calcium on the iron status was mixed. The inverse dose-response association of calcium intake with the serum ferritin concentration was significant (P value = 0.0004). There was, however, no reduction in the hemoglobin concentration (WMD = 1.22g/L;  95% CI:  0.37-2.07).

CONCLUSIONS

The existing body of studies is insufficient to make recommendations with high confidence due to heterogeneity in designs, limitations of ferritin as an iron biomarker, and a lack of intake studies in pregnant women. Prescribing separation of prenatal calcium and iron supplements in free-living individuals is unlikely to affect the anemia burden. There is a need for effectiveness trials comparing the effects of prescribing separated intake to concurrent intake, with functional endpoints as primary outcomes and adherence to each supplement as intermediate outcomes.

Iron Fortification Practices and Implications for Iron Addition to Salt

This introductory article provides an in-depth technical background for iron fortification, and thus introduces a series of articles in this supplement designed to present the current evidence on the fortification of salt with both iodine and iron, that is, double-fortified salt (DFS). This article reviews our current knowledge of the causes and consequences of iron deficiency and anemia and then, with the aim of assisting the comparison between DFS and other common iron-fortified staple foods, discusses the factors influencing the efficacy of iron-fortified foods. This includes the dietary and physiological factors influencing iron absorption; the choice of an iron compound and the fortification technology that will ensure the necessary iron absorption with no sensory changes; encapsulation of iron fortification compounds to prevent unacceptable sensory changes; the addition of iron absorption enhancers; the estimation of the iron fortification level for each vehicle based on iron requirements and consumption patterns; and the iron status biomarkers that are needed to demonstrate improved iron status in populations regularly consuming the iron-fortified food. The supplement is designed to provide a summary of evidence to date that can help advise policy makers considering DFS as an intervention to address the difficult public health issue of iron deficiency anemia, while at the same time using DFS to target iodine deficiency.

Iron-Enriched Nutritional Supplements for the 2030 Pharmacy Shelves

Iron deficiency (ID) affects people of all ages in many countries. Due to intestinal blood loss and reduced iron absorption, ID is a threat to IBD patients, women, and children the most. Current therapies can efficiently recover normal serum transferrin saturation and hemoglobin concentration but may cause several side effects, including intestinal inflammation. ID patients may benefit from innovative nutritional supplements that may satisfy iron needs without side effects. There is a growing interest in new iron-rich superfoods, like algae and mushrooms, which combine antioxidant and anti-inflammatory properties with iron richness.

Iron Absorption from Iron-Biofortified Sweetpotato Is Higher Than Regular Sweetpotato in Malawian Women while Iron Absorption from Regular and Iron-Biofortified Potatoes Is High in Peruvian Women

BACKGROUND

Sweetpotato and potato are fast-maturing staple crops and widely consumed in low- and middle-income countries. Conventional breeding to biofortify these crops with iron could improve iron intakes. To our knowledge, iron absorption from sweetpotato and potato has not been assessed.

OBJECTIVE

The aim was to assess iron absorption from regular and iron-biofortified orange-fleshed sweetpotato in Malawi and yellow-fleshed potato and iron-biofortified purple-fleshed potato in Peru.

METHODS

We conducted 2 randomized, multiple-meal studies in generally healthy, iron-depleted women of reproductive age. Malawian women (n = 24) received 400 g regular or biofortified sweetpotato test meals and Peruvian women (n = 35) received 500 g regular or biofortified potato test meals. Women consumed the meals at breakfast for 2 wk and were then crossed over to the other variety. We labeled the test meals with 57Fe or 58Fe and measured cumulative erythrocyte incorporation of the labels 14 d after completion of each test-meal sequence to calculate iron absorption. Iron absorption was compared by paired-sample t tests.

RESULTS

The regular and biofortified orange-fleshed sweetpotato test meals contained 0.55 and 0.97 mg Fe/100 g. Geometric mean (95% CI) fractional iron absorption (FIA) was 5.82% (3.79%, 8.95%) and 6.02% (4.51%, 8.05%), respectively (P = 0.81), resulting in 1.9-fold higher total iron absorption (TIA) from biofortified sweetpotato (P < 0.001). The regular and biofortified potato test meals contained 0.33 and 0.69 mg Fe/100 g. FIA was 28.4% (23.5%, 34.2%) from the regular yellow-fleshed and 13.3% (10.6%, 16.6%) from the biofortified purple-fleshed potato meals, respectively (P < 0.001), resulting in no significant difference in TIA (P = 0.88).

CONCLUSIONS

FIA from regular yellow-fleshed potato was remarkably high, at 28%. Iron absorbed from both potato test meals covered 33% of the daily absorbed iron requirement for women of reproductive age, while the biofortified orange-fleshed sweetpotato test meal covered 18% of this requirement. High polyphenol concentrations were likely the major inhibitors of iron absorption. These trials were registered at www.clinicaltrials.gov as NCT03840031 (Malawi) and NCT04216030 (Peru).

Impact of Ascorbic Acid on the In Vitro Iron Bioavailability of a Casein-Based Iron Fortificant

A new iron–casein complex (ICC) has been developed for iron (Fe) fortification of dairy matrices. The objective was to assess the impact of ascorbic acid (AA) on its in vitro bioavailability in comparison with ferrous sulfate (FeSO₄) and ferric pyrophosphate (FePP). A simulated digestion coupled with the Caco-2 cell culture model was used in parallel with solubility and dissociation tests. Under diluted acidic conditions, the ICC was as soluble as FeSO₄, but only part of the iron was found to dissociate from the caseins, indicating that the ICC was an iron chelate. The Caco-2 cell results in milk showed that the addition of AA (2:1 molar ratio) enhanced iron uptake from the ICCs and FeSO₄ to a similar level (p = 0.582; p = 0.852) and to a significantly higher level than that from FePP (p < 0.01). This translated into a relative in vitro bioavailability to FeSO₄ of 36% for FePP and 114 and 104% for the two ICCs. Similar results were obtained from water. Increasing the AA to iron molar ratio (4:1 molar ratio) had no additional effect on the ICCs and FePP. However, ICC absorption remained similar to that from FeSO₄ (p = 0.666; p = 0.113), and was still significantly higher than that from FePP (p < 0.003). Therefore, even though iron from ICC does not fully dissociate under gastric digestion, iron uptake suggested that ICCs are absorbed to a similar amount as FeSO₄ in the presence of AA and thus provide an excellent source of iron.

Iron bioavailability of a casein-based iron fortificant compared with that of ferrous sulfate in whole milk: a randomized trial with a crossover design in adult women

BACKGROUND

A highly soluble iron-casein complex has been developed for food fortification purposes with the aim to provide high iron bioavailability.

OBJECTIVE

We aimed to determine the iron bioavailability of the iron-casein complex relative to that of ferrous sulfate (control) when given with whole milk in healthy young women.

METHODS

A randomized comparator-controlled trial with a crossover design was conducted using the erythrocyte incorporation dual stable isotope (57Fe, 58Fe) technique. Iron absorption from the iron-casein complex was compared with that from ferrous sulfate in 21 healthy women aged 20-38 y with normal iron status.

RESULTS

Fractional iron absorption (geometric mean; -SD, +SD) from the iron-casein complex (3.4%; 1.4%, 5.4%) and from ferrous sulfate (3.9%; 1.7%, 6.1%) were not statistically different (P > 0.05). The relative bioavailability value of the iron-casein complex to ferrous sulfate was determined to be 0.87 (-1 SD, +1 SD: -0.90, +2.64).

CONCLUSIONS

The iron-casein complex has iron bioavailability comparable to that of ferrous sulfate in healthy young women. This trial was registered at www.anzctr.org.au as ACTRN12615000690550.

Soya, maize and sorghum ready-to-use therapeutic foods are more effective in correcting anaemia and iron deficiency than the standard ready-to-use therapeutic food: randomized controlled trial

BACKGROUND

The prevalence of anaemia and iron deficiency (ID) among children with severe acute malnutrition (SAM) and their correction during nutritional rehabilitation are not well documented. This study assessed anaemia and ID prevalence and their predictors at start of SAM treatment, and the efficacy of their treatment and effect on gut health of two novel Ready-To-Use Therapeutic foods (RUTF) prepared from soybean, maize and sorghum (SMS) with (MSMS-RUTF) or without added milk (FSMS-RUTF) compared to those of the standard formulation prepared from peanut and milk (PM-RUTF).

METHODS

This was a 3-arms parallel groups, simple randomised, controlled non-inferiority trial in 6-59 months old Central Malawian children with SAM. Anaemia was defined using altitude- and ethnicity-adjusted haemoglobin. Iron status was defined using soluble transferrin receptor (sTfR) and body iron stores (BIS). We used Pearson's chi-square test, t-test for paired or unpaired data, Kruskal-Wallis test for between-arm differences as appropriate and logistic regression to identify independent predictors of anaemia or iron deficiency anaemia (IDA).

RESULTS

The sample size was 389. At admission, the prevalence [%(95%CI)] of anaemia was 48.9(41.4-56.5)% while that of ID and IDA were 55.7(48.6-62.5)% and 34.3(28.2-41.0)% when using sTfR criterion and 29.1(24.4-34.4)% and 28.9(23.7-34.9)% when using BIS criterion, respectively. At discharge, nutrition rehabilitation with SMS-RUTF was associated with the lowest prevalence of anaemia [12.0(6.9-20.3)% for FSMS-RUTF, 18.2(11.9-26.8)% for MSMS-RUTF and 24.5(15.8-35.9)% for PM-RUTF; p = 0.023] and IDA [7.9(3.4-17.3)% for FSMS-RUTF, 10.9(4.8-22.6)% for MSMS-RUTF and 20.5(10.7-35.5)% for PM-RUTF; p = 0.028]. SMS-RUTF was also associated with the highest increase in BIS [Change in BIS (95%CI)] among the iron deplete at admission [6.2 (3.7; 8.6), 3.2 (0.8; 5.6), 2.2 (0.2; 4.3) for the same study arms; Anova p = 0.045]. Compared to P-RUTF, FSMS-RUTF had the highest adjusted recovery rate [OR (95%CI = 0.3 (0.2-0.5) with p < 0.001 for FSMS-RUTF and 0.6 (0.3-1.0) with p = 0.068 for MSMS-RUTF]. No effect of iron content on risk of iron overload or gut inflammation was observed.

CONCLUSIONS

Anaemia and ID are common among children with SAM. FSMS-RUTF is more efficacious in treating anaemia and correcting BIS among this group than PM-RUTF.

TRIAL REGISTRATION

This study was registered on 15 April 2015 ( PACTR201505001101224 ).

Improving Workplace-Based Intervention in Indonesia to Prevent and Control Anemia

Purpose: The present study determined female workers' experiences and preferences to improve the workplace anemia prevention program in Indonesia by studying their perception of anemia, as well as its risk factors and control. Methods: This qualitative study was conducted using focus group discussions (FGDs) to assess female workers' understanding about anemia and possible improvements for workplace-based intervention in a factory located in East Jakarta, Indonesia. Participants were consisted of 14 FGD groups according to anemia status and potential affecting characteristics, including marital status, ethnicity, religion, and frequency of medical consultations. A semistructured questionnaire was used to determine participants' ideas and experiences of anemia control. Results: A total of 14 FGDs were conducted including 105 female workers who participated in this study. More than half of the participants showed a good understanding of the signs and symptoms of anemia. They expected the company to improve the factory health service by improving accessibility and affordability of food and controlling hazardous substances considered risk factors of anemia in the workplace. Conclusion: Female workers have valuable experience and ideas that should be considered to improve workplace-based anemia intervention. They proposed improvement of workplace-based health services such as improving factory canteen and clinics services and controlling potential anemia risk hazards in the workplace.

The bioavailability of iron picolinate is comparable to iron sulfate when fortified into a complementary fruit yogurt: a stable iron isotope study in young women

Purpose

A technological gap exists for the iron (Fe) fortification of difficult-to-fortify products, such as wet and acid food products containing polyphenols, with stable and bioavailable Fe. Fe picolinate, a novel food ingredient, was found to be stable over time in this type of matrix. The objective of this study was to measure the Fe bioavailability of Fe picolinate in a complementary fruit yogurt.

Methods

The bioavailability of Fe picolinate was determined using stable iron isotopes in a double blind, randomized cross-over design in non-anemic Swiss women (n = 19; 25.1 ± 4.6 years). Fractional Fe absorption was measured from Fe picolinate (2.5 mg ⁵⁷Fe per serving in two servings given morning and afternoon) and from Fe sulfate (2.5 mg ⁵⁴Fe per serving in two servings given morning and afternoon) in a fortified dairy complementary food (i.e. yogurt containing fruits). Fe absorption was determined based on erythrocyte incorporation of isotopic labels 14 days after consumption of the last test meal.

Results

Geometric mean (95% CI) fractional iron absorption from Fe picolinate and Fe sulfate were not significantly different: 5.2% (3.8–7.2%) and 5.3% (3.8–7.3%) (N.S.), respectively. Relative bioavailability of Fe picolinate versus Fe sulfate was 0.99 (0.85–1.15).

Conclusion

Therefore, Fe picolinate is a promising compound for the fortification of difficult-to-fortify foods, to help meet Fe requirements of infants, young children and women of childbearing age.

Acceptability and efficacy of ready-to-use therapeutic food using soy protein isolate in under-5 children suffering from severe acute malnutrition in Bangladesh: a double-blind randomized non-inferiority trial

BACKGROUND AND OBJECTIVE

Globally, around 20 million children suffer from severe acute malnutrition (SAM). Identifying a more economical treatment for those affected has the potential to make treatment more available and improve prognosis for recovery and future health.

DESIGN/METHODS

The double-blind randomized study compared taste acceptability (measured by the eagerness to eat) and efficacy of soy-based RUTF (S-RUTF) with milk-based RUTF (M-RUTF) in 6- to 59-month-old children suffering from SAM (WHZ < -3) at icddr,b, in Bangladesh. These SAM children were enrolled in the study after completion of their stabilization phase of treatment. Tolerance of test-RUTF was also tested during the efficacy trial.

RESULTS

The cross-over taste acceptability study, conducted in 36 children, revealed similar results between products and an absence of side effects. The efficacy trial enrolled 260 children (130, each group) with similar baseline characteristics, including mean ± SD age 15.0 ± 8.0 months, WHZ - 3.41 ± 0.40 and mid-upper arm circumference (MUAC) 11.1 ± 0.7 cm. The features at the end of study by RUTF group were (in S-RUTF vs. M-RUTF, respectively): total days from enrollment: 44 ± 34 versus 39 ± 30; weight gain (kg): 0.698 ± 0.438 versus 0.741 ± 0.381 and rate of weight gain (g/kg/d): 3.9 ± 3.2 versus 5.2 ± 4.6; MUAC gain (cm): 0.9 ± 0.7 versus 0.9 ± 0.6; and improvement of WHZ: 1.12 ± 0.82 versus 1.22 ± 0.68 (all data were man ± SD and none were significantly different between the groups). At enrollment and the end of intervention, the body composition [total body water (TBW): 70.3 ± 3.2 vs. 69.9 ± 3.5%, and fat: 11.0 ± 4.0 vs.11.5 ± 4.3% at baseline; and TBW: 65.5 ± 4.1 vs. 65.9 ± 4.6%; and fat: 16.8 ± 5.2 vs. 16.2 ± 5.8% in S-RUTF and M-RUTF group, respectively] was found similar. Moreover, the increment of total TBW, FM, and FFM was also observed similar between the groups.

CONCLUSIONS

This is the first randomized trial comparing S-RUTF using soy protein isolate with milk-based RUTF including comparison of body composition. S-RUTF was found equally acceptable as of milk-based RUTF without any adverse event. Children receiving S-RUTF showed similar pattern of changes in anthropometric indices, and body composition as of milk-based RUTF. Greater number of SAM children can be managed in the community with comparatively low-cost soy-based RUTF.

TRIAL REGISTRATION

NCT01634009.

Biomarkers of Nutrition for Development (BOND)-Iron Review

This is the fifth in the series of reviews developed as part of the Biomarkers of Nutrition for Development (BOND) program. The BOND Iron Expert Panel (I-EP) reviewed the extant knowledge regarding iron biology, public health implications, and the relative usefulness of currently available biomarkers of iron status from deficiency to overload. Approaches to assessing intake, including bioavailability, are also covered. The report also covers technical and laboratory considerations for the use of available biomarkers of iron status, and concludes with a description of research priorities along with a brief discussion of new biomarkers with potential for use across the spectrum of activities related to the study of iron in human health.The I-EP concluded that current iron biomarkers are reliable for accurately assessing many aspects of iron nutrition. However, a clear distinction is made between the relative strengths of biomarkers to assess hematological consequences of iron deficiency versus other putative functional outcomes, particularly the relationship between maternal and fetal iron status during pregnancy, birth outcomes, and infant cognitive, motor and emotional development. The I-EP also highlighted the importance of considering the confounding effects of inflammation and infection on the interpretation of iron biomarker results, as well as the impact of life stage. Finally, alternative approaches to the evaluation of the risk for nutritional iron overload at the population level are presented, because the currently designated upper limits for the biomarker generally employed (serum ferritin) may not differentiate between true iron overload and the effects of subclinical inflammation.

Comparative assessment and suitability of iron and the nutritional composition of fortified foods for young children

AIM

To assess the suitability of iron content and the nutritional benefits of selected fortified food products marketed for 4-8 year old children in Oman.

METHODS

Forty-five fortified foods, which are available in Omani markets, were classified into four groups based on food type and composition: ready-to-eat (RTE) breakfast cereals (two groups), malted milk drinks and milk powder formulas. The nutrition panel displayed on the products' outer package was used as a source of content values for iron and other nutrients.

RESULTS

Among the selected products, malted milk drinks contain a significant ( p < 0.001) amount of iron that is 6.2±3.1 mg per 30 g serving (recommended daily intake for children 4-8 years old is 10 mg). The way selected products are served, with milk or water, could have a significant impact on the iron absorption and bioavailability, which is influenced by the presence of calcium and vitamin C. The values recorded from malted milk drinks and milk powder formulas were shown to have vitamin C to iron ratios of 3:1 and 8:1, respectively. Such ratios are reportedly effective in reversing the negative effect of calcium on iron absorption. Iron-fortified foods contain low to moderate amount of iron per serving and are considered more nutritious when compared to iron supplements.

CONCLUSION

Iron-fortified foods can be conditionally useful to prevent or restore iron deficiency but not be relied on as an only source of iron. Hence these products must be consumed as a part of a healthy diet plan.

Soya, maize, and sorghum-based ready-to-use therapeutic food with amino acid is as efficacious as the standard milk and peanut paste-based formulation for the treatment of severe acute malnutrition in children: a noninferiority individually randomized controlled efficacy clinical trial in Malawi

Background: Development of more cost-effective ready-to-use therapeutic food (RUTF) is a global public health priority. To date, previous lower-cost recipes have been less effective than the standard peanut and milk (PM)-based RUTF, particularly in children aged <24 mo.Objective: We aimed to compare the efficacy of the PM-RUTF to a milk-free soya, maize, and sorghum (FSMS)-RUTF enriched with crystalline amino acids without cow milk powder and a milk, soya, maize, and sorghum (MSMS)-RUTF containing 9.3% skim cow milk powder.Design: This nonblinded, 3-arm, parallel-group, simple randomized controlled trial enrolled Malawian children with severe acute malnutrition.Results: In intention-to-treat analyses, FSMS-RUTF showed noninferiority for recovery rates in children aged 24-59 mo (Δ: -1.9%; 95% CI: -9.5%, 5.6%) and 6-23 mo (Δ: -0.2%; 95% CI: -7.5%, 7.1%) compared with PM-RUTF. MSMS-RUTF also showed noninferiority for recovery rates in children aged 24-59 mo (Δ: 0.0%; 95% CI: -7.3%, 7.4%) and 6-23 mo (Δ: 0.6%; 95% CI: -4.3%, 5.5%). Noninferiority in recovery rates was also observed in per-protocol analyses. For length of stay in the program (time to cure), both FSMS-RUTF in children aged 24-59 mo (Δ: 2.8 d; 95% CI: -0.8, 6.5 d) and 6-23 mo (Δ: 3.4 d; 95% CI: -1.2, 8.0 d) and MSMS-RUTF in children aged 24-59 mo (Δ: 0.2 d; 95% CI: -3.1, 3.6 d) and 6-23 mo (Δ: 1.2 d; 95% CI: -3.4, 5.8 d) were not inferior to PM-RUTF. FSMS-RUTF was also significantly better than PM-RUTF at increasing hemoglobin and body iron stores in anemic children, with mean hemoglobin increases of 2.1 (95% CI: 1.6, 2.6) and 1.3 (95% CI: 0.9, 1.8) and mean body iron store increases of 2.0 (95% CI: 0.8, 3.3) and 0.1 (95% CI: -1.1, 1.3) for FSMS-RUTF and PM-RUTF, respectively.Conclusions: FSMS-RUTF without milk is efficacious in the treatment of severe acute malnutrition in children aged 6-23 and 24-59 mo. It is also better at correcting iron deficiency anemia than PM-RUTF. This trial was registered at www.pactr.org as PACTR201505001101224.

Vitamin C in Stem Cell Biology: Impact on Extracellular Matrix Homeostasis and Epigenetics

Transcription factors and signaling molecules are well-known regulators of stem cell identity and behavior; however, increasing evidence indicates that environmental cues contribute to this complex network of stimuli, acting as crucial determinants of stem cell fate. l-Ascorbic acid (vitamin C (VitC)) has gained growing interest for its multiple functions and mechanisms of action, contributing to the homeostasis of normal tissues and organs as well as to tissue regeneration. Here, we review the main functions of VitC and its effects on stem cells, focusing on its activity as cofactor of Fe⁺²/αKG dioxygenases, which regulate the epigenetic signatures, the redox status, and the extracellular matrix (ECM) composition, depending on the enzymes' subcellular localization. Acting as cofactor of collagen prolyl hydroxylases in the endoplasmic reticulum, VitC regulates ECM/collagen homeostasis and plays a key role in the differentiation of mesenchymal stem cells towards osteoblasts, chondrocytes, and tendons. In the nucleus, VitC enhances the activity of DNA and histone demethylases, improving somatic cell reprogramming and pushing embryonic stem cell towards the naive pluripotent state. The broad spectrum of actions of VitC highlights its relevance for stem cell biology in both physiology and disease.