The impact of a meat- versus a vegetable-based diet on iron status in women of childbearing age with small iron stores

Animal board invited review: The contribution of red meat to adult nutrition and health beyond protein

Red meat has been a critical part of human diets for millennia, providing a source of high-quality protein, micronutrients and essential fatty acids. However, as societies evolved and industrialisation reshaped our food systems, there has been a noticeable shift in meat-eating trends driven by concerns about the environmental impact of meat production and its potential risk to health. Yet, despite falling out of favour with some dietary experts and influencers, meat has an important role in a healthy diet and most adults still consume it. This article explores the nutritional value of red meat, authorised nutrition and health claims, how red meat fits into diet, providing the example of the United Kingdom (UK), and the health benefits and risks associated with both eating and avoiding red meat. Benefits of red meat include nutrient density and bioavailability while risks include colorectal cancer at high intakes of processed meats, based on observational studies. Benefits of meat-free diets include a lower risk of chronic diseases, based on observational studies, while risks include nutrient inadequacy, higher bone fracture risk and low protein quality. Hence, a wholesale shift to plant-based diets may not benefit adults who are vulnerable to sub-optimal nutrient intakes, such as women of child-bearing age and the elderly. More evidence from randomised controlled trials is recommended to fully understand the benefits and risks of both meat-containing and meat-free diets.

Body Fat Percentage and Blood Donation are the Strongest Determinants of Iron Stores in Premenopausal Women Joining the New Zealand Army

INTRODUCTION

Suboptimal iron status is an issue for women joining the military because of its association with impaired aerobic performance, yet no studies have investigated dietary and non-dietary determinants of iron status simultaneously in this population. The purpose of this study was to explore associations between iron stores, dietary patterns (DPs), and potential non-dietary determinants of iron status in premenopausal women at the commencement of basic military training (BMT) in the New Zealand Army.

METHODS

During week 1 of BMT, demographic, body composition, lifestyle, medical history, and dietary data were measured as potential determinants of serum ferritin (SF) in 101 participants. Following univariate analysis, age, body fat percentage, previous blood donation, at least 6 h of exercise per week that raised the heart rate, and a vegetarian DP were analyzed using a multiple linear regression model.

RESULTS

An increase in body fat percentage was associated with increased SF (P < .009), although blood donation in the past year decreased SF (P < .011) compared to those participants who did not donate blood. There was no association between SF and a vegetarian DP or hours of exercise per week. The model explained 17.5% of the variance in SF at the commencement of BMT.

CONCLUSION

Body fat percentage and blood donation in the past year were the strongest determinants of iron stores in healthy premenopausal women commencing BMT. It is recommended that women joining the New Zealand Army are provided information to maintain or improve their iron status based on these findings. This includes clinical screening of iron status, advice for women considering blood donation, and dietary advice regarding total energy requirements and iron bioavailability.

Effectiveness of Dietary Intervention with Iron and Vitamin C Administered Separately in Improving Iron Status in Young Women

In order to maintain an adequate iron status in young women, effective dietary interventions should provide sufficient amounts of iron in everyday meals and improve the bioavailability of non-heme iron by providing vitamin C. While some intervention studies administering products rich in vitamin C in conjunction with iron sources showed improved iron status, it is unknown whether a separate administration of products rich in iron and vitamin C may be a successful strategy as well. The aim of this study was to assess the effectiveness of dietary intervention with iron and vitamin C administered separately in improving iron status in young women to prevent iron deficiency anemia. The study was conducted in a group of 29 women aged 18-30, and an 8-week dietary intervention was performed. Study participants with an adequate iron status received 50 g of iron-fortified oat flakes (as a source of non-heme iron) with breakfast and 200 mL of orange juice (as a source of vitamin C) in the second part of the day. Iron status was analyzed based on red blood cells, hemoglobin, hematocrit, serum ferritin, and serum iron, and it was assessed at baseline, after 4 weeks, and after 8 weeks of the intervention. The intakes of iron, vitamin C, and folate were controlled throughout the study period, and menstrual blood loss was estimated. After 8 weeks of intervention, statistically significant differences compared with baseline were observed only for hematocrit, as its level after 8 weeks of intervention was higher than the baseline (p = 0.0491). Comparing subsamples within the dietary intervention considered effective and ineffective for red blood cell levels, it was indicated that lower baseline vitamin C intake may result in a more effective dietary intervention (p = 0.0231). Comparing subsamples within the dietary intervention considered effective and ineffective for hemoglobin, hematocrit, iron, and serum ferritin levels, it was indicated that higher baseline levels of hemoglobin (p = 0.0143), hematocrit (p = 0.0497), iron (p = 0.0101), and serum ferritin (p = 0.0343) respectively may result in a more effective dietary intervention. It was concluded that dietary intervention with iron and vitamin C administered separately may be effective in improving iron status in young women to prevent iron deficiency anemia. It may be concluded that in the studied group, a better baseline iron status and lower baseline vitamin C intake may result in a more effective dietary intervention with iron and vitamin C administered separately to improve iron status in young women.

Lower Non-Heme Iron Absorption in Healthy Females from Single Meals with Texturized Fava Bean Protein Compared to Beef and Cod Protein Meals: Two Single-Blinded Randomized Trials

Meat analogs based on plant protein extracts are rising in popularity as meat consumption declines. A dietary shift away from meat, which has a high iron bioavailability, may have a negative effect on the amount of iron absorbed from the diet. Iron absorption from legumes cultivated in regions not suitable for soy production, such as fava bean, has not yet been explored. The aim of this study was to evaluate non-heme iron absorption from a meal with texturized fava bean protein compared to beef and cod protein meals. The study included two single-blinded iron isotope trials in healthy Swedish women of the ages 18–45 years, each of whom served as their own control. The participants were served matched test meals containing beef and fava bean protein (Study 1) or cod and fava bean protein (Study 2) with radiolabeled non-heme iron 55Fe and 59Fe. The absorption of non-heme iron from test meals was measured by whole-body counting and erythrocyte incorporation. The absorption of non-heme iron, measured as erythrocyte incorporation ratio, from beef protein meal was 4.2 times higher compared to texturized fava bean meal, and absorption from cod protein meal was 2.7 times higher compared to the fava bean meal. The adjusted non-heme iron absorption, normalized to a 40% reference dose uptake, was 9.2% for cod protein meal, 21.7% for beef protein meal, and 4.2% for texturized fava bean meal. A fava bean protein meal has markedly lower iron bioavailability in healthy females compared with a meal of beef or cod protein. Therefore, a dietary shift from meat and fish protein to fava bean protein may increase the risk of iron deficiency.

Effectiveness of Dietary Interventions to Treat Iron-Deficiency Anemia in Women: A Systematic Review of Randomized Controlled Trials

Iron-deficiency anemia is the most frequent nutritional deficiency, with women of reproductive age being particularly at risk of its development. The aim of the systematic review was to assess the effectiveness of dietary interventions to treat iron-deficiency anemia in women based on the randomized controlled trials. The systematic review was conducted according to the PRISMA guidelines and registered in the PROSPERO database (CRD42021261235). The searching procedure was based on PubMed and Web of Science databases, while it covered records published until June 2021. It included all randomized controlled trials assessing effectiveness of various dietary interventions on treatment of iron-deficiency anemia in women of childbearing age. The total number of 7825 records were screened, while 14 of them were finally included in the systematic review. The studies were screened, included, and reported, and the risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials by two independent researchers. The included studies compared the effectiveness of various dietary interventions with supplementation, placebo, control, or any other dietary intervention, while the assessed dietary interventions were based either on increasing iron supply and/or on increasing its absorption (by increasing vitamin C or vitamin D or decreasing phytate intake). The duration of applied intervention was diversified from 3 months or less, through 4 or 5 months, to half of a year or more. Among the assessed biochemical measures, the following were analyzed in majority of studies: hemoglobin, ferritin, transferrin receptor, hematocrit, and transferrin. The majority of included studies supported the influence of dietary interventions on the treatment of iron-deficiency anemia, as the applied dietary intervention was not effective in only three studies. The majority of included studies were assessed as characterized by medium risk of bias, while the overall risk was high for only four studies, which resulted from the randomization process, deviations from the intended interventions, and selection of the reported result. The majority of included studies were conducted for increasing iron supply and/or increasing vitamin C supply; however, only for the interventions including increasing iron supply and simultaneously increasing its absorption by vitamin C supply were all results confirmed effective. Vitamin D also seems to be an effective dietary treatment, but further studies are necessary to confirm the observations. Considering this fact, dietary interventions recommended for anemic female patients should include increased intake of iron and vitamin C.

Nutrient-Optimized Beef Enhances Blood Levels of Vitamin D and Selenium among Young Women

Bovine meat provides healthy nutrients but has also been negatively linked to greenhouse gases and non-communicable diseases. A double-blind intervention study was carried out to compare beef meat from bulls fed with feed supplemented with selenium, vitamin D, E, K (SeDEK-feed), and n-3, or REGULAR feed. Thirty-four young healthy women (19–29 years old) consumed 300 g of these beef types per day for 6 days in a cross-over design. Diet registrations, blood samples, anthropometric measurements, and clinical data were collected four times. Both beef diets were higher than their habitual diet in protein, fat, saturated fat, and several micronutrients; contained more vegetables and fewer carbohydrates and were followed by a higher feeling of satiety. The SeDEK beef had higher amounts of selenium, vitamin 25-hydroxyvitamin D3 (25(OH)D3), E, and K (MK4), and increased serum selenium and 25(OH)D3 from the participants’ normal values if they were below 85 µg/L of selenium and 30 nmol of 25(OH)D3/L, respectively. Our study showed that optimized beef increased serum selenium in young women having moderate selenium levels and improved blood 25(OH)D3 in a woman having low to normal 25(OH)D3. Meat should be optimized to increase specific consumer groups’ needs for selenium and vitamin D.

Managing Genetic Hemochromatosis: An Overview of Dietary Measures, Which May Reduce Intestinal Iron Absorption in Persons With Iron Overload

Genetic hemochromatosis causes iron overload by excess absorption of dietary iron, due to a decreased expression of hepcidin. The objective was to elaborate dietary recommendations that can reduce intestinal iron absorption in hemochromatosis patients, based on our present knowledge of the iron contained in nutrients and the mechanisms of iron uptake. This is a narrative review. Literature search in PubMed and Google Scholar of papers dealing with iron absorption from the diet was conducted. Most important proposed dietary recommendations are: 1) Choose a varied vegetarian, semi-vegetarian or flexitarian diet. A “veggie-lacto-ovo-poultry-pescetarian” diet seems optimal. Avoid iron enriched foods and iron supplements. 2) Eat many vegetables and fruits, at least 600 g per day. Choose protein rich pulses and legumes (e.g., kidney- and soya beans). Fresh fruits should be eaten between meals. 3) Abstain from red meat from mammals and choose the lean, white meat from poultry. Avoid processed meat, offal and blood containing foods. Eat no more than 200 g meat from poultry per week. Choose fish, eggs, vegetables and protein rich legumes the other days. Eat fish two to four times a week as main course, 350 - 500 g fish per week, of which half should be fat fish. 4) Choose whole grain products in cereals and bread. Avoid iron enriched grains. Choose non-sourdough, yeast-fermented bread with at least 50% whole grain. 5) Choose vegetable oils, and low-fat dairy products. 6) Eat less sugar and salt. Choose whole foods and foods with minimal processing and none or little added sugar or salt. 7) Quench your thirst in water. Drink green- or black tea, coffee, or low-fat milk with the meals, alternatively water or non-alcoholic beer. Fruit juices must be consumed between meals. Abstain from alcoholic beverages. Drink soft drinks, non-alcoholic beer, or non-alcoholic wine instead. These advices are close to the official Danish dietary recommendations in 2021. In the management of hemochromatosis, dietary modifications that lower iron intake and decrease iron bioavailability may provide additional measures to reduce iron uptake from the foods and reduce the number of phlebotomies. However, there is a need for large, prospective, randomized studies that specifically evaluate the effect of dietary interventions.

A Review of Nutrients and Compounds, Which Promote or Inhibit Intestinal Iron Absorption: Making a Platform for Dietary Measures That Can Reduce Iron Uptake in Patients with Genetic Haemochromatosis

Objective

To provide an overview of nutrients and compounds, which influence human intestinal iron absorption, thereby making a platform for elaboration of dietary recommendations that can reduce iron uptake in patients with genetic haemochromatosis.

Design

Review. Setting. A literature search in PubMed and Google Scholar of papers dealing with iron absorption.

Results

The most important promoters of iron absorption in foods are ascorbic acid, lactic acid (produced by fermentation), meat factors in animal meat, the presence of heme iron, and alcohol which stimulate iron uptake by inhibition of hepcidin expression. The most important inhibitors of iron uptake are phytic acid/phytates, polyphenols/tannins, proteins from soya beans, milk, eggs, and calcium. Oxalic acid/oxalate does not seem to influence iron uptake. Turmeric/curcumin may stimulate iron uptake through a decrease in hepcidin expression and inhibit uptake by complex formation with iron, but the net effect has not been clarified.

Conclusions

In haemochromatosis, iron absorption is enhanced due to a decreased expression of hepcidin. Dietary modifications that lower iron intake and decrease iron bioavailability may provide additional measures to reduce iron uptake from the foods. This could stimulate the patients' active cooperation in the treatment of their disorder and reduce the number of phlebotomies.

Efficacy of a High-Iron Dietary Intervention in Women with Celiac Disease and Iron Deficiency without Anemia: A Clinical Trial

Background and Aim. Iron deficiency without anemia (IDWA) is a common finding in celiac disease (CD) and can also persist in case of good compliance and clinical response to a strict gluten-free diet (GFD). This scenario usually presents in CD women of child-bearing age in whom the imbalance between menstrual iron loss and inadequate iron intake from their diet plays the major role. A recommended approach to this condition is yet to be established. This study aimed to compare, in this subset of patients, the efficacy of a dietary approach consisting of an iron-rich diet against the traditional pharmacological oral-replacement therapy. Material and Methods. Between February and December 2016, consecutive CD female patients of child-bearing age as referred to our outpatient center with evidence of IDWA (ferritin <15 ng/mL or 15–20 ng/L with transferrin saturation <15%) were enrolled. After the completion of a 7-day weighed food intake recording to assess the usual iron dietary intake, the patients were randomized in two arms to receive a 12-week iron-rich diet (iron intake >20 mg/die) versus oral iron supplementation with ferrous sulfate (FS) (105 mg/day). Blood tests and dietary assessments were repeated at the end of treatment. The degree of compliance and tolerability to the treatments were assessed every month by means of specific questionnaires and symptoms evaluation. Results. A total of 22 women were enrolled and divided in the diet group (n = 10, age 37 ± 8 years) and in the FS group (n = 12, age 38 ± 10 years). The food intake records demonstrated an inadequate daily intake of iron in all the enrolled subjects. At the end of the treatments, ferritin levels were higher in the FS group (8.5 (5) versus 34 (30.8), p = 0.002). Compliance and tolerability were similar in both treatment groups (89% versus 87%, p = ns). Conclusions. These findings did not support any equivalent efficacy of an iron-rich diet compared to a FS supplementation in non-anemic iron-deficient women affected by CD. However, the diet appeared a well-tolerated approach, and adequate dietary instructions could effectively increase the daily iron consumption, suggesting a role in the long-term management of IDWA, especially in patients who do not tolerate pharmacological supplementation.

Iron Absorption from Bouillon Fortified with Iron-Enriched Aspergillus oryzae Is Higher Than That Fortified with Ferric Pyrophosphate in Young Women

BACKGROUND

Bouillon cubes are a potential vehicle for iron fortification. They are currently fortified with ferric pyrophosphate (FePP), which is known to be poorly absorbed. The objective of this study was to assess the iron absorption of Aspergillus oryzae grown in FePP (ASP-p) and compare it with FePP and ferrous sulfate (FeSO4)-fortified bouillon cubes.

METHODS

In 2 single-blinded, crossover studies, healthy women with serum ferritin concentrations <40 μg/L were randomly assigned to consume a rice-vegetable meal with iron-fortified chicken bouillon. Subjects in study I (n = 17, 18-26 y) consumed iron from both iron sources as 57FePP and 58ASP-p (intrinsically labeled with 58FePP) with a meal containing 4.2 mg of total iron provided for 3 d. Study II (n = 18, 18-29 y) was similar except that subjects consumed 57FeSO4 and 58ASP-p. Whole-blood stable isotope enrichment after 14 d was used to measure fractional iron absorption. Hemoglobin, hematocrit, serum ferritin, hepcidin, and serum C-reactive protein were analyzed at baseline and at 14 d. A t test was used to compare the mean differences in fractional absorptions within each study and baseline characteristics between studies.

RESULTS

Geometric mean (95% CI) fractional iron absorption of FePP [0.94% (0.63%, 1.40%)] was lower than ASP-p [2.20% (1.47%, 3.30%)] (P < 0.0001) in study I. In study II, ASP-p fractional absorption [2.98% (2.03%, 4.38%)] was lower than that of FeSO4 [9.88% (6.70%, 14.59%)] (P < 0.0001). Both ferritin (r = -0.41, P = 0.014) and hepcidin (r = -0.42, P = 0.01) concentrations were inversely correlated with ASP-p iron absorption. Fractional absorption of ASP-p was also positively correlated with FePP (r = 0.92, P < 0.0001) and FeSO4 (r = 0.52, P < 0.02) absorption.

CONCLUSIONS

ASP-p-fortified bouillon provided 2.3-fold higher absorbable iron than the currently used FePP. Bouillon fortified with ASP-p may contribute sufficient bioavailable iron to meet the daily iron requirements in young women only if consumed with other iron-fortified staple foods. This trial was registered at clinicaltrials.gov as NCT03586245.

Low-phytate wholegrain bread instead of high-phytate wholegrain bread in a total diet context did not improve iron status of healthy Swedish females: a 12-week, randomized, parallel-design intervention study

PURPOSE

To investigate the effects of eating wholegrain rye bread with high or low amounts of phytate on iron status in women under free-living conditions.

METHODS

In this 12-week, randomized, parallel-design intervention study, 102 females were allocated into two groups, a high-phytate-bread group or a low-phytate-bread group. These two groups were administered: 200 g of blanched wholegrain rye bread/day, or 200 g dephytinized wholegrain rye bread/day. The bread was administered in addition to their habitual daily diet. Iron status biomarkers and plasma alkylresorcinols were analyzed at baseline and post-intervention.

RESULTS

Fifty-five females completed the study. There was a significant difference in change over time in total body iron stores between the two groups (p < 0.035). In the low-phytate bread group (n = 24) there were significant within-group decreases in both ferritin (mean 12%; from 32 ± 7 to 27 ± 6 μg/L, geometric mean ± SEM, p < 0.018) and total body iron (mean 12%; from 6.9 ± 1.4 to 5.4 ± 1.1 mg/kg, p < 0.035). Plasma alkylresorcinols indicated that most subjects complied with the intervention

CONCLUSIONS

In Swedish females of reproductive age, no statistically significant difference in iron status was detected after 12 weeks of high-phytate wholegrain bread consumption. However, consumption of low-phytate wholegrain bread for 12 weeks resulted in a reduction of markers of iron status. Although single-meal studies clearly show an increase in iron bioavailability from dephytinization of cereals, medium-term consumption of reduced phytate bread under free-living conditions suggests that this strategy does not work to improve iron status in healthy women of reproductive age.

The effect of vegetarian diets on iron status in adults: A systematic review and meta-analysis

BACKGROUND

Vegetarian diets exclude meat, seafood, and products containing these foods. Although the vegetarian lifestyle could lead to a better health status in adults, it may also bear risks for certain nutritional deficiencies. Cross-sectional studies and narrative reviews have shown that the iron status of vegetarians is compromised by the absence of highly bioavailable haem-iron in meatless diets and the inhibiting effect of certain components present in plant foods on non-haem iron bioavailability.

METHODS

The databases Pubmed, Scopus, Embase, and Cochrane CentralRegister of Controlled Trials were searched for studies comparing serum ferritin, as the major laboratory parameter for iron status of adult vegetarians with non-vegetarian control groups. A qualitative review was conducted as well as an inverse-variance random-effects meta-analysis to pool available data. In addition the effect of vegetarian diets according to gender was investigated with a subgroup analysis. The results were validated using a sensitivity analysis.

RESULTS

A total of 27 cross-sectional studies and three interventional studies were selected for the systematic review. The meta-analysis which combined data of 24 cross-sectional studies showed that adult vegetarians have significantly lower serum ferritin levels than their non-vegetarian controls (-29.71 µg/L, 95% CI [-39.69, -19.73], p < 0.01). Inclusion of semi-vegetarian diets did not change the results considerably (-23.27 µg/L, 95% CI [-29.77, -16.76], p < 0.01). The effects were more pronounced in men (-61.88 µg/L, 95% CI [-85.59, -38.17], p < 0.01) than in both premenopausal women (-17.70 μg/L, 95% CI [-29.80, -5.60], p < 0.01) and all women (-13.50 μg/L, 95% CI [-22.96, -4.04], p < 0.01), respectively.

CONCLUSIONS

In conclusion our results showed that vegetarians are more likely to have lower iron stores compared with non-vegetarians. However, since high iron stores are also a risk factor for certain non-communicable diseases, such as type 2 diabetes, it is recommended that not only vegetarians but also non-vegetarians should regularly control their iron status and improve their diet regarding the content and bioavailability of iron by consuming more plants and less meat.

An Animal-Source Food Supplement Increases Micronutrient Intakes and Iron Status among Reproductive-Age Women in Rural Vietnam

Background: Few studies have examined the impact of local animal-source foods (ASFs) on the nutritional status of reproductive-age women in developing countries.Objective: We hypothesized that a midmorning snack of local ASF for 6 mo would reduce dietary micronutrient deficiencies [usual intake less than the estimated average requirement (EAR)] and improve blood biomarkers of iron, zinc, and vitamins A and B-12 status among nonpregnant, reproductive-age women in rural Vietnam.Methods: One hundred seventeen women, 18-30 y old, were randomly assigned to receive either an ASF (mean: 144 kcal, 8.9 mg Fe, 2.7 mg Zn, 1050 μg retinoic acid equivalent vitamin A, and 5.5 μg vitamin B-12) or a control snack (mean: 150 kcal, 2.0 mg Fe, 0.9 mg Zn, 0 μg retinoic acid equivalent vitamin A, and 0 μg vitamin B-12) 5 d/wk for 6 mo. Usual nutrient intakes were estimated by repeated 24-h dietary recalls. Blood samples were collected at baseline and 3 and 6 mo. Because of the relation between nutritional status and inflammation, serum C-reactive protein, α-1-acid-glycoprotein, and urinary tract infections (UTIs) were also monitored.Results: Eighty-nine women (47 in the ASF group and 42 controls) completed the study. In the ASF group, intakes of iron and vitamins A and B-12 below the EAR were eliminated, and the prevalence of a low zinc intake was reduced to 9.6% compared with 64.7% in controls (P < 0.001). At 6 mo, a modest increase (P < 0.05) in hemoglobin and iron status occurred in the ASF group compared with the control group, but plasma zinc, retinol, and serum vitamin B-12 concentrations did not differ. UTI relative risk was 3.9 (P < 0.05) among women assigned to the ASF group who had a low whole-body iron status at baseline.Conclusions: Adding a small amount of locally produced ASF to the diets of reproductive-age Vietnamese women improved micronutrient intakes and iron status. However, the increased UTI incidence in women in the ASF group with initially lower iron stores warrants further investigation.

Is Higher Consumption of Animal Flesh Foods Associated with Better Iron Status among Adults in Developed Countries? A Systematic Review

Iron deficiency (ID) is the most prevalent nutrient deficiency within the developed world. This is of concern as ID has been shown to affect immunity, thermoregulation, work performance and cognition. Animal flesh foods provide the richest and most bioavailable source of dietary (haem) iron, however, it is unclear whether low animal flesh diets contribute to ID. This systematic review aimed to investigate whether a higher consumption of animal flesh foods is associated with better iron status in adults. CINAHL, Cochrane, EMBASE and MEDLINE were searched for published studies that included adults (≥18 years) from developed countries and measured flesh intakes in relation to iron status indices. Eight experimental and 41 observational studies met the inclusion criteria. Generally, studies varied in population and study designs and results were conflicting. Of the seven high quality studies, five showed a positive association between animal flesh intake (85-300 g/day) and iron status. However, the optimum quantity or frequency of flesh intake required to maintain or achieve a healthy iron status remains unclear. Results show a promising relationship between animal flesh intake and iron status, however, additional longitudinal and experimental studies are required to confirm this relationship and determine optimal intakes to reduce ID development.

Dietary determinants of and possible solutions to iron deficiency for young women living in industrialized countries: a review

Iron deficiency is a concern in both developing and developed (industrialized) countries; and young women are particularly vulnerable. This review investigates dietary determinants of and possible solutions to iron deficiency in young women living in industrialized countries. Dietary factors including ascorbic acid and an elusive factor in animal protein foods (meat; fish and poultry) enhance iron absorption; while phytic acid; soy protein; calcium and polyphenols inhibit iron absorption. However; the effects of these dietary factors on iron absorption do not necessarily translate into an association with iron status and iron stores (serum ferritin concentration). In cross-sectional studies; only meat intake has consistently (positively) been associated with higher serum ferritin concentrations. The enhancing effects of ascorbic acid and meat on iron absorption may be negated by the simultaneous consumption of foods and nutrients which are inhibitory. Recent cross-sectional studies have considered the combination and timing of foods consumed; with mixed results. Dietary interventions using a range of focused dietary measures to improve iron status appear to be more effective than dietary approaches that focus on single nutrients or foods. Further research is needed to determine optimal dietary recommendations for both the prevention and treatment of iron deficiency.

Ferrous bisglycinate 25 mg iron is as effective as ferrous sulfate 50 mg iron in the prophylaxis of iron deficiency and anemia during pregnancy in a randomized trial

OBJECTIVE

To compare the effects of oral ferrous bisglycinate 25 mg iron/day vs. ferrous sulfate 50 mg iron/day in the prevention of iron deficiency (ID) and iron deficiency anemia (IDA) in pregnant women.

DESIGN

Randomized, double-blind, intention-to-treat study.

SETTING

Antenatal care clinic.

SAMPLE

80 healthy ethnic Danish pregnant women.

METHODS

Women were allocated to ferrous bisglycinate 25 mg elemental iron (Aminojern®) (n=40) or ferrous sulfate 50 mg elemental iron (n=40) from 15 to 19 weeks of gestation to delivery. Hematological status (hemoglobin, red blood cell indices) and iron status (plasma iron, plasma transferrin, plasma transferrin saturation, plasma ferritin) were measured at 15-19 weeks (baseline), 27-28 weeks and 36-37 weeks of gestation.

MAIN OUTCOME MEASURES

Occurrence of ID (ferritin <15 μg/L) and IDA (ferritin <12 μg/L and hemoglobin <110 g/L).

RESULTS

At inclusion, there were no significant differences between the bisglycinate and sulfate group concerning hematological status and iron status. The frequencies of ID and IDA were low and not significantly different in the two iron groups. The frequency of gastrointestinal complaints was lower in the bisglycinate than in the sulfate group (P=0.001). Newborns weight was slightly higher in the bisglycinate vs. the sulfate group (3601±517 g vs. 3395±426 g, P=0.09).

CONCLUSIONS

In the prevention of ID and IDA, ferrous bisglycinate was not inferior to ferrous sulfate. Ferrous bisglycinate in a low dose of 25 mg iron/day appears to be adequate to prevent IDA in more than 95% of Danish women during pregnancy and postpartum.

Anaemia among school children older than five years in the Volta Region of Ghana

INTRODUCTION

Anaemia among children is a public health issue in Ghana. The Ghana School Feeding Programme (GSFP) was instituted on pilot basis in an effort to provide nutritious lunch to school children. Evidence on the nutritional status of pupils is needed to inform the expansion of GSFP. This study sought to assess anaemia among Ghanaian pupils.

METHODS

This cross-sectional study involved a random sample of 143 pupils aged 6 to 12 years. Blood samples were collected and analysed for serum-ferritin (SF), C-reactive protein (CRP), haemoglobin and malaria-parasitaemia (MP). Stool samples were examined for soil-transmitted helminths. Dietary data were collected using the 24 hour-recall method on three non-consecutive days and a food frequency questionnaire. The Student's t-test was used to compare mean values between sexes. Binary logistic regression was performed to identify factors associated with anaemia. Statistical significance was set at p < 0.05.

RESULTS

SF and haemoglobin concentrations were 23.9 ± 15 ng/ml and 120 ± 11 g/L respectively. The prevalence of anaemia was 30.8%. More females (41.5%) than males (21.8%) had anaemia (p < 0.005). Seventy-one percent of pupils had low SF levels. MP prevalence was 67.8%. Hookworm infestation was only observed in males (18.0%). Dietary iron and vitamin C intakes were 18.98 ± 8.8 mg and 23.7 ± 6.7 mg, respectively. Child's sex, SF and MP were associated with anaemia. Males had a lower likelihood of being anaemic (OR = 0.2, CI 0.1-0.5, p = 0.002).

CONCLUSION

The study findings underscore the need for multi-pronged approaches that address both malaria control and nutrition in order to reduce anaemia among pupils.

Potential of phytase-mediated iron release from cereal-based foods: a quantitative view

The major part of iron present in plant foods such as cereals is largely unavailable for direct absorption in humans due to complexation with the negatively charged phosphate groups of phytate (myo-inositol (1,2,3,4,5,6)-hexakisphosphate). Human biology has not evolved an efficient mechanism to naturally release iron from iron phytate complexes. This narrative review will evaluate the quantitative significance of phytase-catalysed iron release from cereal foods. In vivo studies have shown how addition of microbially derived phytases to cereal-based foods has produced increased iron absorption via enzyme-catalysed dephosphorylation of phytate, indicating the potential of this strategy for preventing and treating iron deficiency anaemia. Despite the immense promise of this strategy and the prevalence of iron deficiency worldwide, the number of human studies elucidating the significance of phytase-mediated improvements in iron absorption and ultimately in iron status in particularly vulnerable groups is still low. A more detailed understanding of (1) the uptake mechanism for iron released from partially dephosphorylated phytate chelates, (2) the affinity of microbially derived phytases towards insoluble iron phytate complexes, and (3) the extent of phytate dephosphorylation required for iron release from inositol phosphates is warranted. Phytase-mediated iron release can improve iron absorption from plant foods. There is a need for development of innovative strategies to obtain better effects.

Beneficial impact on cardiovascular risk profile of water buffalo meat consumption

BACKGROUND/OBJECTIVES

Meat is a good source of proteins and irons, yet its consumption has been associated with unfavorable cardiovascular effects. Whether this applies to all types of meat is unclear. We thus aimed to appraise the impact of water buffalo meat consumption on cardiovascular risk profile with an observational longitudinal study.

SUBJECTS/METHODS

Several important cardiovascular risk features were appraised at baseline and at 12-month follow-up in 300 adult subjects divided in groups: recent consumers of water buffalo meat vs subjects who had never consumed water buffalo meat. In addition, long-standing consumers of water buffalo meat were evaluated.

RESULTS

Age, gender, height, body weight, and the remaining diet (with the exception of cow meat consumption) were similar across groups. From baseline to follow-up, recent consumers of water buffalo meat change their intake of water buffalo meat from none to 600+/-107 g per week (P<0.001), with ensuing reductions in cow meat consumption from 504+/-104 to 4+/-28 (P<0.001). At the end of the study, recent consumers of water buffalo meat showed a significant decrease in total cholesterol and triglycerides levels, lower pulse wave velocity, as well as a more blunted response to oxidative stress from baseline to follow-up in comparison with subjects who had never consumed water buffalo meat (all P<0.05).

CONCLUSIONS

Consumption of buffalo meat seems to be associated with several beneficial effects on cardiovascular risk profile. Awaiting further randomized clinical trials, this study suggests that a larger consumption of water buffalo meat could confer significant cardiovascular benefits, while continuing to provide a substantial proportion of the recommended daily allowance of protein.