The importance of bioavailability of dietary iron in relation to the expected effect from iron fortification

Celiac disease and depressive disorders as nutritional implications related to common factors - A comprehensive review

Celiac disease (CD) is an immune-mediated disease affecting the small intestine. The only treatment strategy for CD is the gluten-free diet (GFD). One of the more common mental disorders in CD patients is major depressive disorder (MDD). The influence of GFD on the occurrence of MDD symptoms in patients with CD will be evaluated. This diet often reduces nutritional deficiencies in these patients and also helps to reduce depressive symptoms. Both disease entities are often dominated by the same deficiencies of nutrients such as iron, zinc, selenium, iodine, or B and D vitamins. Deficiencies of particular components in CD can favor MDD and vice versa. Gluten can adversely affect the mental state of patients without CD. Also, intestinal microbiota may play an important role in the described process. This work aims to comprehensively assess the common factors involved in the pathomechanisms of MDD and CD, with particular emphasis on nutrient imbalances. Given the complexity of both disease entities, and the many common links, more research related to improving mental health in these patients and the implementation of a GFD would need to be conducted, but it appears to be a viable pathway to improving the quality of life and health of people struggling with CD and MDD. Therefore, probiotics, micronutrients, macronutrients, and vitamin supplements are recommended to reduce the risk of MDD, given that they may alleviate the symptoms of both these disease entities. In turn, in patients with MDD, it is worth considering testing for CD.

Effects of various Fe compounds on the bioavailability of Pb contained in orally ingested soils in mice: Mechanistic insights and health implications

Reducing lead (Pb) exposure via oral ingestion of contaminated soils is highly relevant for child health. Elevating dietary micronutrient iron (Fe) intake can reduce Pb oral bioavailability while being beneficial for child nutritional health. However, the practical performance of various Fe compounds was not assessed. Here, based on mouse bioassays, ten Fe compounds applied to diets (100-800 mg Fe kg^-1) reduced Pb oral relative bioavailability (RBA) in two soils variedly depending on Fe forms. EDTA-FeNa was most efficient, which reduced Pb-RBA in a soil from 79.5 ± 14.7 % to 23.1 ± 2.72 % (71 % lower) at 100 mg Fe kg^-1 in diet, more effective than other 9 compounds at equivalent or higher doses (3.6-68 % lower). When EDTA-FeNa, ferrous gluconate, ferric citrate, and ferrous bisglycinate were supplemented, Fe-Pb co-precipitation was not observed in the intestinal tract. EDTA-FeNa, ferrous gluconate, ferric citrate, and ferrous sulfate suppressed duodenal divalent metal transporter 1 (DMT1)mRNA relative expression similarly (27-68 % lower). In comparison, among ten compounds, EDTA-FeNa elevated Fe concentrations in mouse liver, kidney, and blood (1.50-2.69-fold higher) most efficiently, suggesting the most efficient Fe absorption that competed with Pb. In addition, EDTA was unique from other organic ligands, ingestion of which caused 12.0-fold higher Pb urinary excretion, decreasing Pb concentrations in mouse liver, kidney, and blood by 68-88 %. The two processes (Fe-Pb absorption competition and Pb urinary excretion with EDTA) interacted synergistically, leading to the lowest Pb absorption with EDTA-FeNa. The results provide evidence of a better inhibition of Pb absorption by EDTA-FeNa, highlighting that EDTA-FeNa may be the most appropriate supplement for intervention on human Pb exposure. Future researches are needed to assess the effectiveness of EDTA-FeNa for intervention on human Pb exposure.

Development and evaluating the biopotency of ready to eat liver meat balls in fighting anaemia and vitamin A deficiency, improving selected nutritional biochemical indicators and promoting the cognitive function among mildly anaemic Egyptian children aged 3-9 years

OBJECTIVE

Ready to eat fried liver meat balls (LMB) were developed to fight anaemia and vitamin A deficiency and promote cognitive function.

DESIGN

Randomised controlled trial consisting of two arms: control group with no supplement and LMB group receiving LMB supplement three times a week for 90 d. Criteria of evaluations included dietary assessment, anthropometric measurements, laboratory investigations and cognitive function by Wechsler test.

SETTING

Kinder Garten and primary school in Urban Giza.

PARTICIPANTS

Sixty boys and girls aging 3-9 years.

RESULTS

The LMB supplement contributed to significant increases in the intakes of high bioavailable Fe and vitamin A in the diets of all children. Initial overall prevalence of mild and moderate anaemia was 43 %, which disappeared completely from all children aging < 72 months and from 88 % of children ≥ 72 months after the 90 d dietary intervention with the LMB. Faecal systemic immune globulin A, urinary hydroxyproline index and urinary iodine excretion increased significantly (P < 0·05) only after the dietary intervention with the LMB supplement for 90 d. The standard scores of verbal and non-verbal cognitive function tests (Δ day 90-day 0) increased significantly (P < 0·05) among the LMB group compared with the respective changes observed among the control group. The increase in height-for-age Z score and blood Hb were good predictors for improvement in cognitive function.

CONCLUSION

LMB supplement is effective sustainable nutritious biotherapeutic food in fighting hidden hunger and promoting the cognitive function.

Lifestyle Strategies to Boost Total Body Iron

Patients who switch to a whole food plant-based eating pattern (WFPBD) generally have an uneventful transition, but may present with dizziness and lightheadedness. Research demonstrates that anemia is no more common when transitioning to a WFPBD than in the normal population, but Iron deficiency is possible in the context of a transition to a whole food plant-based diet resulting in either microcytic or normocytic anemia. All six pillars of lifestyle medicine; diet, activity, sleep, stress, social engagement, and risky substances, can affect absorption of Iron and are discussed. This paper discusses how the use of lifestyle modifications can potentiate iron supplementation, or replace the need for it altogether, to reverse anemia.

Iron Fortification through Universal Distribution of Double-Fortified Salt Can Increase Wages and Be Cost-Effective: An Ex-Ante Modeling Study in India

BACKGROUND

The alleviation of iron deficiency through iron supplementation has not effectively reduced anemia in India, mainly due to low compliance. Food fortification with iron is considered a viable alternative, and the provision of double-fortified salt (DFS; with iron and iodine) has been mandated in public health programs. Limited evidence exists on its benefit-cost ratio.

OBJECTIVE

In this study we sought to estimate the economic benefit in terms of increased wages in relation to introduction of DFS in reduction of anemia and the cost of doing so.

METHODS

The economic benefit of introducing DFS in India was derived using a series of mathematical, statistical, and econometric models using data from national surveys capturing earnings and dietary iron intake of the population. Anemia status was predicted from data on dietary intake, sanitation, and for women, menstrual losses. The impact of iron deficiency anemia (IDA) on wages was estimated using a Heckman Selection model and 2-stage least squares procedure. Benefit of DFS was estimated through increased wages attributed to anemia reduction compared with its cost.

RESULTS

Men and women with IDA had lower wages (by 25.9%, 95% CI: 11.3, 38.1; and by 3.9%, 95% CI: 0.0, 7.7, respectively) than those without IDA. Additional iron intake through DFS was predicted to reduce prevalence of IDA (from 10.6% to 0.7% in men and 23.8% to 20.9% in women). The economic benefit-cost ratio of introducing DFS at a national level was estimated to be 4.2:1.

CONCLUSIONS

Iron fortification delivered through DFS under a universal program can improve wages and be sufficiently cost-effective for its implementation at scale in India.

Iron Deficiency in Heart Failure: Mechanisms and Pathophysiology

Iron is an essential micronutrient for a myriad of physiological processes in the body beyond erythropoiesis. Iron deficiency (ID) is a common comorbidity in patients with heart failure (HF), with a prevalence reaching up to 59% even in non-anaemic patients. ID impairs exercise capacity, reduces the quality of life, increases hospitalisation rate and mortality risk regardless of anaemia. Intravenously correcting ID has emerged as a promising treatment in HF as it has been shown to alleviate symptoms, improve quality of life and exercise capacity and reduce hospitalisations. However, the pathophysiology of ID in HF remains poorly characterised. Recognition of ID in HF triggered more research with the aim to explain how correcting ID improves HF status as well as the underlying causes of ID in the first place. In the past few years, significant progress has been made in understanding iron homeostasis by characterising the role of the iron-regulating hormone hepcidin, the effects of ID on skeletal and cardiac myocytes, kidneys and the immune system. In this review, we summarise the current knowledge and recent advances in the pathophysiology of ID in heart failure, the deleterious systemic and cellular consequences of ID.

Anemia in Sports: A Narrative Review

Recent years have brought about new understandings regarding the pathogenesis of anemia in sports. From hemodilution and redistribution considered to contribute to the so-called “sports anemia” to iron deficiency caused by increased demands, dietary restrictions, decreased absorption, increased losses, hemolysis, and sequestration, to genetic determinants of different types of anemia (some related to sport), the anemia in athletes deserves a careful and multifactorial approach. Dietary factors that reduce iron absorption (e.g., phytate, polyphenols) and that augment iron’s bioavailability (e.g., ascorbic acid) should be considered. Celiac disease, more prevalent in female athletes, may underlie an unexplained iron deficiency anemia. Iron loss during exercise occurs in several ways: sweating, hematuria, gastrointestinal bleeding, inflammation, and intravascular and extravascular hemolysis. From a practical point of view, assessing iron status, especially in the athletes at risk for iron deficiency (females, adolescents, in sports with dietary restrictions, etc.), may improve the iron balance and possibly the performance. Hemoglobin and serum ferritin are measures that are easily employable for the evaluation of patients’ iron status. Cutoff values should probably be further assessed with respect to the sex, age, and type of sport. A healthy gut microbiome influences the iron status. Athletes at risk of iron deficiency should perform non-weight-bearing, low-intensity sports to avoid inducing hemolysis.

Nutrient and Chemical Contaminant Levels in Five Marine Fish Species from Angola-The EAF-Nansen Programme

Fish is a rich source of several important nutrients and an important part of the otherwise plant-dominated diet present in Angola. However, fish may also be a source of contaminants. The aim of this study was to analyse the nutrient contents and the levels of chemical contaminants, including arsenic, cadmium, mercury, and lead, in five commonly consumed marine fish species sampled during a survey with the research vessel Dr. Fridtjof Nansen in Angola. The species' contribution to recommended nutrient intakes (RNI) for women and children was assessed and compared to that of food products of terrestrial animal origin. All the sampled species are good sources of protein and micronutrients if included in the diet, and inter-species variation is evident. The species were identified to contribute 5-15% of the RNI for calcium, iron, iodine, and zinc and exceeded the contribution to protein and iron intakes of food products of terrestrial animal origin. Furthermore, the potential consumer exposure to chemical contaminants in the species was assessed. None of the species exceeded the maximum levels for cadmium, mercury, and lead, and the potential consumer exposure to cadmium and methylmercury was considered low. The data presented in this study represent an important contribution to African food composition tables.

Dietary Iron Intake and Anemia Are Weakly Associated, Limiting Effective Iron Fortification Strategies in India

BACKGROUND

Anemia prevalence in India remains high despite preventive iron supplementation programs. Consequently, concurrent national policies of iron fortification of staple foods have been initiated.

OBJECTIVES

This study evaluated the relation between dietary iron intake and anemia (hemoglobin <12 g/dL) in women of reproductive age (WRA; 15-49 y) with respect to iron fortification in India.

METHODS

Data from 2 national surveys were used. Data on hemoglobin in WRA were sourced from the National Family Health Survey-4, whereas dietary intakes were sourced from the National Sample Survey. Adjusted odds for anemia with increasing iron intake were estimated, along with the effect of modulating nutrients such as vitamins B-12 and C, from statistically matched household data from the 2 surveys. The risks of inadequate (less than the Estimated Average Requirement for WRA) and excess (more than the tolerable upper limit for WRA) intakes of iron were estimated by the probability approach.

RESULTS

The relation between iron intake and the odds of anemia was weak (OR: 0.992; 95% CI: 0.991, 0.994); increasing iron intake by 10 mg/d reduced the odds of anemia by 8%. Phytate and vitamin B-12 and C intakes modified this relation by reducing the odds by 1.5% when vitamin B-12 and C intakes were set at 2 μg/d and 40 mg/d, respectively. The additional intake of 10 mg/d of fortified iron reduced the risk of dietary iron inadequacy from 24-94% to 9-39% across states, with no risk of excess iron intake. Approximately doubling this additional iron intake reduced the risk of inadequacy to 2-12%, but the risk of excess intake reached 22%.

CONCLUSIONS

Providing fortified iron alone may not result in substantial anemia reduction among WRA in India and could have variable benefits and risks across states. Geographically nuanced dietary strategies that include limited fortification and the intake of other beneficial nutrients should be carefully considered.

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.

Dietary Iron Bioavailability: Agreement between Estimation Methods and Association with Serum Ferritin Concentrations in Women of Childbearing Age

Predictive iron bioavailability (FeBio) methods aimed at evaluating the association between diet and body iron have been proposed, but few studies explored their validity and practical usefulness in epidemiological studies. In this cross-sectional study involving 127 women (18–42 years) with presumably steady-state body iron balance, correlations were checked among various FeBio estimates (probabilistic approach and meal-based and diet-based algorithms) and serum ferritin (SF) concentrations. Iron deficiency was defined as SF < 15 µg/L. Pearson correlation, Friedman test, and linear regression were employed. Iron intake and prevalence of iron deficiency were 10.9 mg/day and 12.6%. Algorithm estimates were strongly correlated (0.69≤ r ≥0.85; p < 0.001), although diet-based models (8.5–8.9%) diverged from meal-based models (11.6–12.8%; p < 0.001). Still, all algorithms underestimated the probabilistic approach (17.2%). No significant association was found between SF and FeBio from Monsen (1978), Reddy (2000), and Armah (2013) algorithms. Nevertheless, there was a 30–37% difference in SF concentrations between women stratified at extreme tertiles of FeBio from Hallberg and Hulthén (2000) and Collings’ (2013) models. The results demonstrate discordance of FeBio from probabilistic approach and algorithm methods while suggesting two models with best performances to rank individuals according to their bioavailable iron intakes.

Freeze-dried Lactobacillus plantarum 299v increases iron absorption in young females-Double isotope sequential single-blind studies in menstruating women

BACKGROUND

The probiotic strain Lactobacillus plantarum 299v has earlier been shown to increase iron absorption when added to foods. However, it is not known if the same probiotic strain in a freeze-dried format included in a capsule increases the iron absorption.

OBJECTIVE

The aim of this study was to test the hypotheses that non-heme iron absorption from a light meal is promoted by a simultaneous intake of freeze-dried Lactobacillus plantarum 299v (Lp299v, DSM 9843).

STUDY DESIGN

With a single blinded placebo controlled sequential design, iron absorption from a light breakfast meal administered with or without capsules containing 1010 cfu freeze-dried Lp299v was studied in healthy female volunteers of fertile age. The methodology used was a double isotope technique (59Fe and 55Fe). Two studies were performed using the same protocol.

RESULTS

In study 1, the absorption of iron from a meal without Lp299v was found to be 17.4 ± 13.4%, and from an identical meal with Lp299v was found to be 22.4 ± 17.3% (mean ± SD). This difference was statistically significant (p = 0.040, n = 14). In study 2, the absorption of iron from a meal without Lp299v was found to be 20.9 ± 13.1%, and from an identical meal with Lp299v found to be 24.5 ± 12.0% (mean ± SD, n = 28), which again was statistically significant (p = 0.003).

CONCLUSION

Freeze-dried Lp299v enhances the absorption of iron when administered together with a meal with a high iron bioavailability.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02131870.

Dietary strategies for improving iron status: balancing safety and efficacy

In light of evidence that high-dose iron supplements lead to a range of adverse events in low-income settings, the safety and efficacy of lower doses of iron provided through biological or industrial fortification of foodstuffs is reviewed. First, strategies for point-of-manufacture chemical fortification are compared with biofortification achieved through plant breeding. Recent insights into the mechanisms of human iron absorption and regulation, the mechanisms by which iron can promote malaria and bacterial infections, and the role of iron in modifying the gut microbiota are summarized. There is strong evidence that supplemental iron given in nonphysiological amounts can increase the risk of bacterial and protozoal infections (especially malaria), but the use of lower quantities of iron provided within a food matrix, ie, fortified food, should be safer in most cases and represents a more logical strategy for a sustained reduction of the risk of deficiency by providing the best balance of risk and benefits. Further research into iron compounds that would minimize the availability of unabsorbed iron to the gut microbiota is warranted.

Probiotic strain Lactobacillus plantarum 299v increases iron absorption from an iron-supplemented fruit drink: a double-isotope cross-over single-blind study in women of reproductive age

Iron deficiency is common, especially among young women. Adding probiotics to foods could be one way to increase iron absorption. The aim of this study was to test the hypothesis that non-haem iron absorption from a fruit drink is improved by adding Lactobacillus plantarum 299v (Lp299v). Iron absorption was studied in healthy women of reproductive age using a single-blind cross-over design in two trials applying the double-isotope (⁵⁵Fe and ⁵⁹Fe) technique. In Trial 1, iron absorption from a fruit drink containing 10⁹ colony-forming units (CFU) Lp299v was compared with that from a control drink without Lp299v. Trial 2 had the same design but 10¹⁰ CFU were used. The test and control drinks contained approximately 5 mg of iron as ferrous lactate and were labelled with ⁵⁹Fe (B) and ⁵⁵Fe (A), respectively, and consumed on 4 consecutive days in the order AABB. Retention of the isotopes was measured with whole-body counting and in blood. Mean iron absorption from the drink containing 10⁹ CFU Lp299v (28·6(sd 12·5) %) was significantly higher than from the control drink (18·5(sd 5·8) %), n 10, P<0·028). The fruit drink with 10¹⁰ CFU Lp299v gave a mean iron absorption of 29·1(sd 17·0) %, whereas the control drink gave an absorption of (20·1(sd 6·4) %) (n 11, P<0·080). The difference in iron absorption between the 10⁹ CFU Lp299v and the 10¹⁰ CFU Lp299v drinks was not significant (P=0·941). In conclusion, intake of probiotics can increase iron absorption by approximately 50 % from a fruit drink having an already relatively high iron bioavailability.

Heme iron-based dietary intervention for improvement of iron status in young women

OBJECTIVE

Conventional iron deficiency treatment with pharmacologic iron doses often causes side effects. Heme iron has high bioavailability and a low capacity to cause gastrointestinal side effects. This study investigated the possibility of using heme iron in the form of blood-based crisp bread as a diet-based treatment program to improve the iron status of women of reproductive age.

METHODS

In a 12-wk intervention study, 77 women (mean age 24 y) were assigned to one of four groups: blood-based crisp bread (35 mg of iron [Fe], 27 mg of which was heme Fe), iron supplementation consisting of 35 mg of non-heme iron/day (Fe35), iron supplementation consisting of 60 mg of non-heme iron/day (Fe60), and controls (iron-free tablets).

RESULTS

Body iron increased significantly in the crisp bread group by a median of 2.7 mg/kg (interquartile range 3.1, n = 18), in the Fe35 group by 2.7 mg/kg (interquartile range 2.8, n = 11), and in the Fe60 group by 4.1 mg/kg (interquartile range 3.6, n = 13), whereas no change was observed in the control group. No statistically significant difference in iron status increase was observed between the crisp bread group compared with the two iron-supplemented groups.

CONCLUSION

Dietary-based treatment containing heme iron has few side effects and can be used efficiently to improve the iron status of women of reproductive age.

Randomized, double-blind, placebo-controlled trial of an iron-fortified food product in female soldiers during military training: relations between iron status, serum hepcidin, and inflammation

BACKGROUND

Iron status degrades in female soldiers during military training. Inflammation-mediated up-regulation of hepcidin, a key mediator of iron homeostasis, may be a contributing factor.

OBJECTIVE

We measured the efficacy of an iron-fortified food product for maintaining iron status in female soldiers during basic combat training (BCT) and examined relations between iron status, serum hepcidin concentrations, and inflammation.

DESIGN

A randomized, double-blind, placebo-controlled trial was conducted. Volunteers received an iron-fortified food product (total dose = 56 mg Fe/d) or a placebo twice daily during the 9-wk BCT course. Iron-status indicators, serum hepcidin concentrations, and markers of inflammation were measured pre- and post-BCT.

RESULTS

BCT affected iron status; serum ferritin concentrations decreased (P < or = 0.05), and concentrations of soluble transferrin receptor (sTfR) and hemoglobin and the red cell distribution width increased (P < or = 0.05). Consumption of the iron-fortified food product attenuated declines in iron status in iron-deficient anemic soldiers; a group-by-time interaction was observed for hemoglobin and sTfR concentrations (P < or = 0.05). Serum hepcidin concentrations were not affected by BCT; however, hepcidin concentrations were lower in iron-deficient anemic soldiers than in those with normal iron status (P < or = 0.05) and were positively associated with serum ferritin (P < or = 0.05) and C-reactive protein (P < or = 0.05) concentrations pre- and post-BCT.

CONCLUSIONS

Twice-daily consumption of an iron-fortified food product improved iron status in iron-deficient anemic soldiers but not in iron-normal or iron-deficient nonanemic soldiers. Serum hepcidin concentrations were not affected by training but were associated with iron status and inflammation pre- and post-BCT. This trial was registered at clinicaltrials.gov as NCT01100905.

Nutritional anemias and the elderly

Nutritional anemias are important because they are easily reversed and because their underlying causes, most often unrelated to dietary intake, require individualized assessment. Iron-deficiency anemia (IDA) usually results from iron losses accompanying chronic bleeding, including loss to intestinal parasites, or from gastric disorders or malabsorption in the elderly. Cobalamin-deficiency anemia, the only nutritional anemia with predilection for the elderly, nearly always stems from failure of intrinsic factor (IF)-related absorption. Folate-deficiency anemia, the only nutritional anemia usually caused by poor intake, has nearly disappeared in countries that fortify food with folic acid. Copper-deficiency anemia, which usually results from malabsorptive disorders or from medical or nutritional interventions that provide inadequate copper or excess zinc, is uncommon but increasingly recognized. The prevalences of nutritional anemias, which are not always distinguished from non-anemic deficiency, are uncertain. The mean corpuscular volume (MCV) provides an essential diagnostic tool leading to judicious matching of relevant biochemical changes with relevant anemia. Nutritional anemias usually feature abnormal MCV, whereas the predominant anemias in the aged, especially the anemias of chronic disease/chronic inflammation (ACD/ACI), of renal failure, and of unknown causes, are typically normocytic.