Thalassemia carrier status and groundwater iron: Implication for iron supplementation program for children in Bangladesh.

Background: Thalassemia, a congenital disorder of hemoglobin synthesis is characterized by low hemoglobin and high iron status, is prevalent in Bangladesh. Iron, consumed through drinking groundwater also increases the population iron status in Bangladesh. The study examined the effect of iron containing micronutrient powder (MNP) on the hemoglobin and ferritin status in Bangladeshi children with thalassemia and their non-thalassemia peers exposed to a high concentration of iron from drinking groundwater. Design and methods: Three hundred twenty-seven children aged 2-5 years were recruited for an MNP efficacy trial. A sub sample (n = 222) were screened for thalassemia. Hemoglobin and ferritin levels were measured in children with and without thalassemia. Intake of iron from the key sources-diet, groundwater and MNP was measured. Mann Whitney and t-test were employed to compare the groups. Results: Hemoglobin concentration of the children with thalassemia at the endpoint remained unchanged relative to the baseline; 11.56 ± 0.59 g/dL (Endpoint) versus 11.6 ± 0.54 g/dL (Baseline), p = 0.83. In children without thalassemia hemoglobin tended to increase; 12.54 ± 0.72 g/dL (Endpoint) versus 12.41 ± 0.72 g/dL (baseline), p = 0.06. Baseline reserve of body iron was significantly (p = 0.03) higher in thalassemia carriers (594 gm) compared to their non-carrier peers (558 gm). The increase of the infection-adjusted ferritin from baseline to the endpoint was 7.37% (p = 0.7) and 10.17% (p = 0.009) in the carrier and non-carrier groups respectively. Conclusions: In Bangladesh, the coexistence of thalassemia and the exposure to a high concentration of iron from drinking groundwater renders anemia prevention program with a low iron MNP potentially lesser hazardous to the thalassemia carriers.

Behind the scene of the prevalence of anaemia: an extended way of reporting.

OBJECTIVE: To develop the methods for an extended reporting of anaemia and to measure the status of the key contextual underlying factors of anaemia. DESIGN: Statistical appraisal of Hb v. key influencers of anaemia in Bangladesh ­ the intake of animal source food (ASF), concentration of Fe in the drinking groundwater (GWI) and the prevalence of congenital Hb disorder (CH) are conducted. The primary data of the National Micronutrient Survey 2011­2012 and the British Geological Survey 2001 are analysed to assess the intake of ASF and the GWI concentration, respectively. The prevalence of thalassaemia from a national survey is used to appraise the CH. ASF is evaluated relative to the 97·5th percentile intake and group scores are assigned. Association of the GWI and Hb is examined by the linear fit and the mspline fit and the group scores are allocated. Group score is allocated for the prevalence of thalassaemia. Inflammation-adjusted ferritin is considered to report Hb. SETTING: A nationwide survey in Bangladesh. PARTICIPANTS: Preschool children (6­59 months), school-age children (6­14 years) and non-pregnant non-lactating women (NPNLW, 15­49 years). RESULTS: The extended reporting to the prevalence of anaemia in Bangladeshi preschool children, school children and women is ­ anaemia 33 % (ASF: 2·08; GWI: 1·75; CH: 2), anaemia 19 % (ASF: 1·98; GWI: 1·56; CH: 2) and anaemia 26 % (ASF: 2·16; GWI: 1·58; CH: 2), respectively. CONCLUSION: The extended reporting of anaemia is a useful tool to understand the status of the key influencers of anaemia, to design the context-customised intervention and to monitor the intervention.

Can guava (Psidium guajava) leaf extracts develop an indigenous, simplified tool for a semi-quantitative assessment of iron in groundwater?

Iron present in the drinking groundwater is attributed to the low burden of iron deficiency (ID) in Bangladesh. The supplemental anemia prevention strategies involving iron need a cautious approach due to the excess load of iron and the side effects. The present pilot study examined the potential of the guava leaf extracts to use as a natural reagent for the assessment of iron in groundwater. Eighteen households with the drinking source of groundwater were randomly selected. Guava leaves were crushed and the shreds of the leaves were mixed with the water sample. Changes of water color were photographed. Five groups were identified - 'whitish', 'shades of pink', 'shades of purple', 'light black' and the 'frank black'. The iron concentration was measured by a test kit device. Each color group was assigned a number on the ordinal scale 1-5. Statistical correlation and agreements were performed between the methods. The positive correlation (Kendall's tau b: 0.89, p < 0.000) and the agreements (Kappa: 0.77, p < 0.000; rho_c: 0.73, p < 0.000) were observed. Guava leaf extracts may standardize an indigenous tool for a semi-quantitative measurement of groundwater iron content. Validation of the tool thus may aid in the design and evaluation of the iron supplementation and fortification programs.

Phytate-iron molar ratio and bioavailability of iron in Bangladesh.

OBJECTIVE: Phytate, an important component of plant origin foods, works as a chelator for mineral nutrients such as iron. Estimating the phytate-iron molar ratio is a traditional method to assess the bioavailability of dietary iron, and a ratio >1 is suggestive of poor absorption of iron through the intestinal mucosa. In Bangladesh, the ratio is considerably higher; nonetheless, the haemoglobin and ferritin status are satisfactory. Hence, we appraised phytate-iron molar ratios and concomitant haemoglobin and ferritin status. METHODS: Dietary intake of iron and phytate was estimated in non-pregnant non-lactating women and school-age children from a nationally representative survey. The phytate-iron molar ratios were estimated. Linear regressions on haemoglobin for the phytate-iron molar ratios and on molar ratios predicting inflammation-adjusted ferritin were performed. RESULTS: The median ratios were 6.12 in women and 5.47 in children, with corresponding haemoglobin concentrations of 12.6 and 12.5 g/dl. Hypothetical lowering of the ratios by ~50% revealed a nominal increment of haemoglobin and ferritin. CONCLUSION: The standard cut-off phytate-iron molar ratio of >1 is inconsistent with the iron and haemoglobin status of the Bangladeshi population. One plausible explanation for the inconsistency is a non-dietary environmental factor-groundwater iron. Isotope studies incorporating the iron from dietary and the drinking groundwater sources are needed to establish a ratio which might better explain iron bioavailability.

Iron content of drinking water is associated with anaemia status among children in high groundwater iron areas in Bangladesh.

OBJECTIVE: Iron in groundwater provides a good source of absorbable iron for humans and can contribute to optimal iron and haemoglobin (Hb) status among populations. We aimed to examine the relationship between the iron content of groundwater and anaemia status among 12- to 23-month-old children in a rural area of Bangladesh. METHOD: A cross-sectional study was conducted in 80 randomly selected unions (the lowest administrative unit) in Sylhet and Moulvibazar districts of Bangladesh. A total of 800 children aged 12-23 months were selected via a systematic random sampling method. The child's age, sex, stunting status, consumption of iron-rich or iron-fortified food, maternal age and maternal body mass index (BMI) and the type of terrain were subjected to multiple logistic regression analysis to observe the independent relationships between groundwater iron content and anaemia in children. RESULTS: In total, 50.4% of children were anaemic. The odds of children being anaemic were 1.51-fold higher [OR: 1.51 (95% CI: 1.09, 2.09)] among households consuming water with an iron content <2 mg/L than in households consuming water with an iron content ≥2 mg/L. Childhood stunting, child's sex, child's age and the type of terrain were also significantly associated with anaemia among children. CONCLUSION: Groundwater with a high iron concentration was significantly associated with a decreased risk of childhood anaemia. This study provides evidence of the importance of groundwater iron to protect impoverished young children from anaemia.

Validation of an interviewer-administered seven-day semi-quantitative food frequency questionnaire for the dietary assessment of preschool children in rural Bangladesh.

A validation study of an interviewer-administered, seven-day semi-quantitative food frequency questionnaire (7-d SQFFQ) was conducted in Bangladeshi rural preschool age children. Using a cross-sectional study design, 105 children from 103 households were randomly selected. For the SQFFQ, a list of commonly consumed foods was adapted from the Bangladesh national micronutrient survey 2011-12. The data on the actual number of times and the amount of the children's consumption of the foods in the preceding 1 week were collected by interviewing the mothers. The intake was compared with two non-consecutive days 24-h dietary recalls conducted within 2 weeks after the SQFFQ. Validity was assessed by the standard statistical tests. After adjusting for the energy intake and de-attenuation for within-subject variation, the food groups (cereals, animal source foods, milk and the processed foods) had 'good' correlations between the methods (rho 0⋅65-0⋅93; P < 0⋅001). Similarly, the macronutrients (carbohydrate, protein and fats) had 'good' correlations (rho 0⋅50-0⋅75; P < 0⋅001) and the key micronutrients (iron, zinc, calcium, vitamin A, etc.) demonstrated 'good' correlations (rho 0⋅46-0⋅85; P < 0⋅001). The variation in classifying the two extreme quintiles by the SQFFQ and the 24-h recalls was <10 %. The results from Lin's concordance coefficients showed a 'moderate' to 'excellent' absolute agreement between the two methods for food groups, and nutrients (0⋅21-0⋅90; P < 0⋅001). This interviewer-administered, 7-d SQFFQ with an open-ended intake frequency demonstrated adequate validity to assess the dietary intake for most nutrients and suitable for dietary assessments of young children in Bangladesh.

Effect of low-iron micronutrient powder (MNP) on the composition of gut microbiota of Bangladeshi children in a high-iron groundwater setting: a randomized controlled trial.

PURPOSE: Adverse effects of iron fortification/supplements such as Micronutrient Powder (MNP) on gut microbiota have previously been found in infection-prone African settings. This study examined the adversaries of a low-iron MNP compared with the standard MNP on the composition of gut microbiota in Bangladeshi children exposed to a high concentration of iron from potable groundwater. METHODS: A randomized controlled trial was conducted in 2- to 5-year-old children, drinking groundwater with a high concentration of iron (≥ 2 mg/L). Children were randomized to receive one sachet per day of either standard MNP (12.5 mg iron) or low-iron MNP (5 mg iron), for 2 months. A sub-sample of 53 children was considered for paired assessment of the gut microbiome by 16S rRNA amplicon sequencing. RESULTS: At baseline, the gut microbiota consisted of Bifidobacteriaceae (15.6%), Prevotellaceae (12.2%), Lactobacillaceae (3.6%), Clostridiaceae (4.1%) and Enterobacteriaceae (2.8%). Overall, there was no significant treatment effect of the low-iron MNP compared to the standard MNP. However, an apparent treatment effect was observed in children with a relative adult-like microbiota, with a higher relative abundance of potentially pathogenic Enterobacteriaceae after receiving the standard MNP compared to the low-iron MNP. This effect, however, was statistically non-significant (p = 0.07). CONCLUSION: In Bangladeshi children drinking iron-rich groundwater, a low-iron MNP supplementation did not have a significant impact on their gut microbiota profile/composition compared to the standard MNP. The trial registration number is ISRCTN60058115; Date of registration 03/07/2019; retrospectively registered.

Adjusting plasma or serum zinc concentrations for inflammation: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project.

BACKGROUND: The accurate estimation of zinc deficiency at the population level is important, as it guides the design, targeting, and evaluation of nutrition interventions. Plasma or serum zinc concentration (PZC) is recommended to estimate zinc nutritional status; however, concentrations may decrease in the presence of inflammation. OBJECTIVES: We aimed to assess the relation between PZC and inflammation in preschool children (PSC; 6-59 mo) and nonpregnant women of reproductive age (WRA; 15-49 y), and to compare different inflammation adjustment approaches, if adjustment is warranted. METHODS: Cross-sectional data from 13 nationally representative surveys (18,859 PSC, 22,695 WRA) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed. Correlation and decile analyses were conducted, and the following 3 adjustment methods were compared if a consistent negative association between PZC and C-reactive protein (CRP) or α-1-acid glycoprotein (AGP) was observed: 1) exclude individuals with CRP > 5 mg/L or AGP > 1 g/L; 2) apply arithmetic correction factors; and 3) use the BRINDA regression correction (RC) approach. RESULTS: In 6 of 12 PSC surveys, the estimated prevalence of zinc deficiency increased with increasing CRP deciles, and to a lesser extent, with increasing AGP deciles. In WRA, the association of PZC with CRP and AGP was weak and inconsistent. In the 6 PSC surveys in which adjustment methods were compared, application of RC reduced the estimated prevalence of zinc deficiency by a median of 11 (range: 4-18) percentage points, compared with the unadjusted prevalence. CONCLUSIONS: Relations between PZC and inflammatory markers were inconsistent, suggesting that correlation and decile analyses should be conducted before applying any inflammation adjustments. In populations of PSC that exhibit a significant negative association between PZC and CRP or AGP, application of the RC approach is supported. At this time, there is insufficient evidence to warrant inflammation adjustment in WRA.

Effect of Micronutrient Powder (MNP) with a Low-Dose of Iron on Hemoglobin and Iron Biomarkers, and Its Effect on Morbidities in Rural Bangladeshi Children Drinking Groundwater with a High-Level of Iron: A Randomized Controlled Trial.

Micronutrient Powder (MNP) is beneficial to control anemia, but some iron-related side-effects are common. A high level of iron in the groundwater used for drinking may exacerbate the side-effects among MNP users. We conducted a randomized controlled trial examining the effect of a low-dose iron MNP compared with the standard MNP in children aged 2-5 years residing in a high-groundwater-iron area in rural Bangladesh. We randomized 327 children, who were drinking from the "high-iron" wells (≥2 mg/L), to receive either standard (12.5 mg iron) or low-dose iron (5.0 mg iron) MNP, one sachet per day for two months. Iron parameters were measured both at baseline and end-point. The children were monitored weekly for morbidities. A generalized linear model was used to determine the treatment effect of the low-dose iron MNP. Poisson regressions were used to determine the incidence rate ratios of the morbidities. The trial was registered at ISRCTN60058115. Changes in the prevalence of anemia (defined as a hemoglobin level < 11.0 g/dL) were 5.4% (baseline) to 1.0% (end-point) in the standard MNP; and 5.8% (baseline) to 2.5% (end-point) in the low-dose iron MNP groups. The low-dose iron MNP was non-inferior to the standard MNP on hemoglobin outcome (ß = -0.14, 95% CI: -0.30, 0.013; p = 0.07). It resulted in a lower incidence of diarrhea (IRR = 0.29, p = 0.01, 95% CI: 0.11-0.77), nausea (IRR = 0.24, p = 0.002, 95% CI: 0.09-0.59) and fever (IRR = 0.26, p < 0.001, 95% CI: 0.15-0.43) compared to the standard MNP. Low-dose iron MNP was non-inferior to the standard MNP in preventing anemia yet demonstrated an added advantage of lowering the key side-effects.

Household coverage of vitamin A fortification of edible oil in Bangladesh.

Mandatory fortification of edible oil (soybean and palm) with vitamin A was decreed in Bangladesh in 2013. Yet, there is a dearth of data on the availability and consumption of vitamin A fortifiable oil at household level across population sub-groups. To fill this gap, our study used a nationally representative survey in Bangladesh to assess the purchase of fortifiable edible oil among households and project potential vitamin A intake across population sub-groups. Data is presented by strata, age range and poverty-the factors that potentially influence oil coverage. Across 1,512 households, purchase of commercially produced fortifiable edible oil was high (87.5%). Urban households were more likely to purchase fortifiable oil (94.0%) than households in rural low performing (79.7%) and rural other strata (88.1%) (p value: 0.01). Households in poverty were less likely to purchase fortifiable oil (82.1%) than households not in poverty (91.4%) (p <0.001). Projected estimates suggested that vitamin A fortified edible oil would at least partially meet daily vitamin A estimated average requirement (EAR) for the majority of the population. However, certain population sub-groups may still have vitamin A intake below the EAR and alternative strategies may be applied to address the vitamin A needs of these vulnerable sub-groups. This study concludes that a high percentage of Bangladeshi population across different sub-groups have access to fortifiable edible oil and further provides evidence to support mandatory edible oil fortification with vitamin A in Bangladesh.

Lower intakes of protein, carbohydrate, and energy are associated with increased global DNA methylation in 2- to 3-year-old urban slum children in Bangladesh.

Stunting in children is a global public health concern. We investigated how global DNA methylation relates to food intakes, dietary diversity, and development of stunting among 324 children aged 24-36 months in a slum community in Dhaka, Bangladesh. Stunted children (height-for-age z score ˂-2; n = 162) and their age- and sex-matched nonstunted counterparts (height-for-age z score ˃-1; n = 162) were selected by active community surveillance. We studied global DNA methylation, measured as 5-mC% content in whole blood. Dietary intake, anthropometric measurement, and sociodemographic information were obtained. In the multiple linear regression model, increased global DNA methylation level in children was significantly associated with consumption of lower amount of energy, coef: .034 (95% CI [.014, .053]); P = .001, protein, coef: .038 (95% CI [.019, .057]); P = .000, carbohydrate, coef: .027 (95% CI [.008, .047]); P = .006, zinc, coef: .020 (95% CI [.001, .039]); P = .043, total dietary intakes, coef: .020 (95% CI [.001, .039]); P = .043, and intake from plant sources, coef: .028 (95% CI [.009, .047]); P = .005, after adjusting for other covariates. Moreover, higher fruits and vegetables consumption was significantly associated with lower 5-mC% level, coef: -.022 (95% CI [-.041, -.002]); P = .028. Our findings suggest a significant association between low dietary intakes and increased global DNA methylation. We also found increased global DNA methylation in stunted children. To establish the relationship among the macronutrient intakes, global DNA methylation, and stunting, future prospective studies are warranted in resource-poor settings.

Magnitude and determinants of inadequate third-trimester weight gain in rural Bangladesh.

OBJECTIVES: The objective of this study was to estimate the magnitude and determinants of inadequate weight gain in the third-trimester among rural women in Matlab, Bangladesh. METHODS: The study analyzed data on weight gain in the third trimester in 1,883 pregnant women in Matlab, Bangladesh. All these women were admitted to Matlab hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) for childbirth during 2012-2014, and they had singleton live births at term. Data were retrieved from the electronic databases of Matlab Health and Demographic Surveillance System and Matlab hospital. A multivariable logistic regression for inadequate weight gain in the third trimester (≤4 kg) was built with sociodemographic, environmental and maternal factors as predictors. RESULTS: One thousand and twenty-six (54%) pregnant women had inadequate weight gain in the third trimester. In the multivariable model, short stature turned out to be the most robust risk factor for inadequate weight gain in the third trimester (OR = 2.5; 95% CI 1.8, 3.5 for short compared to tall women). Pre-third-trimester BMI was inversely associated with insufficient weight gain (OR = 0.96; 95% CI 0.93, 0.99 for 1 unit increase in BMI). Other risk factors for inadequate weight gain in the third trimester were advanced age (OR = 1.9; 95% CI 1.2, 3.1 for ≥35 years compared to ≤19 years), parity (OR = 1.5; 95% CI 1.2, 1.9 for multipara compared to nulliparous women), low socioeconomic status (OR = 1.7; 95% CI 1.2, 2.3 for women in the lowest compared to women in the highest wealth quintile), low level of education (OR = 1.6; 95% CI 1.2, 2.1 for ≤5 years compared to ≥10 years of education), belonging to the Hindu religious community (OR = 1.8; 95% CI 1.3, 2.5), consuming arsenic-contaminated water (OR = 1.4; 95% CI 1.1, 1.9), and conceiving during monsoon or dry season compared to summer (OR = 1.4; 95% CI 1.1, 1.8). CONCLUSIONS: Among rural Bangladeshi women in Matlab, third-trimester weight gain was in general poor. Maternal characteristics such as short stature, low BMI, advanced age, parity, low level of education and socioeconomic status, being Hindu, intake of arsenic contaminated water, and conceiving during monsoon or dry season were the risk factors for inadequate weight gain in the third trimester. Special attention should be given during prenatal care to women with the risk factors identified in this study.

Vitamin A deficiency and determinants of vitamin A status in Bangladeshi children and women: findings of a national survey.

OBJECTIVE: Using data from the national micronutrients survey 2011-2012, the present study explored the status of subclinical vitamin A nutrition and the underlying determinants in the Bangladeshi population. DESIGN: A nationwide cross-sectional study. Settings The survey covered 150 clusters; fifty in each of rural, urban and slum strata. SUBJECTS: Three population groups: (i) pre-school age children (6-59 months; PSAC); (ii) school age children (6-14 years; SAC); and (iii) non-pregnant non-lactating women (15-49 years; NPNLW). RESULTS: National prevalence of subclinical vitamin A deficiency was 20·5, 20·8 and 5·3 % in PSAC, SAC and NPNLW, respectively. Slum populations had higher prevalence compared with urban (PSAC: 38·1 v. 21·2 %, P0·05 for differences in ß between <3 months v. 3-6 months, 6-9 months and 9-12 months). CONCLUSIONS: Prevalence of subclinical vitamin A deficiency was high in children in Bangladesh. Intakes of animal-source foods and leafy vegetables were associated with higher and lower retinol status, respectively. Increased food diversity through animal-source foods is required.

Retraction: Leyvraz M. et al. An Assessment of the Potential Impact of Fortification of Staples and Condiments on Micronutrient Intake of Young Children and Women of Reproductive Age in Bangladesh. Nutrients 2015, 7, 9960-9971.

The published paper [1] contains errors that mean that the resulting analysis is incorrect and the conclusions are no longer supported.[...].

An Assessment of the Potential Impact of Fortification of Staples and Condiments on Micronutrient Intake of Young Children and Women of Reproductive Age in Bangladesh.

Bangladesh has experienced rapid economic growth and achieved major health improvements in the past decade, but malnutrition rates remain high. A nationally representative study conducted in 2011 assessed the dietary habits of 841 children 24-59 months old, 1428 children 6-14 years old, and 1412 nonpregnant, nonlactating women. The study's objective was to assess dietary intakes of key micronutrients and the consumption pattern of potentially fortifiable foods, and then to model the potential impact of the fortification of key staple foods. The current intakes of several micronutrients-namely, iron, zinc, folate, vitamin A, and vitamin B12-were found to be insufficient to meet the needs of Bangladesh's children and women. The fortification of rice with iron and zinc and edible oil with vitamin A has the potential to fill a significant part of the nutrient gap, as these are consumed widely and in significant amounts. Wheat flour and sugar are not as promising food vehicles in the Bangladeshi context, as they were consumed by a smaller portion of the population and in smaller amounts. In conclusion, fortification of rice and oil is recommended to address the large gap in micronutrient intakes.

Status of zinc nutrition in Bangladesh: the underlying associations.

Bangladesh is a country with a high burden of micronutrient malnutrition. Stunting affects 41 % of children aged under 5 years. Zn is one of the key micronutrients that is associated with stunting. The present study, as part of the national micronutrient survey 2011-2012, revealed for the first time the nationally representative prevalence of Zn deficiency and determined the associations of the condition. A cross-sectional 'nationwide' survey was conducted in pre-school-age children (6-59 months; PSAC) and non-pregnant non-lactating women (15-49 years; NPNLW). Multistage random sampling was done in 150 clusters; fifty in each of the rural, urban and slum strata. Data were analysed on 662 PSAC and 1073 NPNLW. Serum Zn was assayed by atomic absorption spectrophotometry. Zn deficiency was defined as serum Zn of <9·9 and <10·1 µmol/l in PSAC and NPNLW, respectively. The national prevalence of Zn deficiency was 44·6 and 57·3 % in PSAC and NPNLW, respectively. In PSAC, it was 29·5, 48·6 and 51·7 %, respectively, in urban, rural and slum strata. Household expenses (ß = 0·13; P = 0·007), Hb (ß = 0·10; P = 0·005), intake of animal-source Zn (ß = 0·096; P = 0·02) and asset score (ß = 0·11; P = 0·03) were positively associated with serum Zn in NPNLW. Residence in an urban area (ß = 0·33; P = 0·03) and intake of plant-origin Zn (ß = -0·13; P = 0·038) determined higher and lower status of Zn in PSAC, respectively. Zn deficiency was highly prevalent in Bangladesh, and it was principally related to inadequate quality of diet. To improve Zn nutrition, Bangladesh needs to strengthen research and programmes related to Zn biofortification, fortification and phytate-reducing technologies in the food system in the short and medium term. In addition, promotion of animal-source Zn for all is important in the long run.

Determinants of iron status and Hb in the Bangladesh population: the role of groundwater iron.

OBJECTIVE: Using data from the national micronutrients survey 2011-2012, the present study explored the determinants of Fe status and Hb levels in Bangladesh with a particular focus on groundwater Fe. DESIGN: Cross-sectional study conducted at the nationwide scale. Settings The survey was conducted in 150 clusters, fifty in each of the three strata of rural, urban and slum. SUBJECTS: Three population groups: pre-school age children (6-59 months; PSAC), school age children (6-14 years; SAC) and non-pregnant non-lactating women (15-49 years; NPNLW). RESULTS: National prevalence of Fe deficiency was 10·7 %, 7·1 % and 3·9-9·5 % in PSAC, NPNLW and SAC, respectively. Prevalence of anaemia was 33·1 % (PSAC), 26·0 % (NPNLW) and 17·1-19·1 % (SAC). Multivariate regression analyses showed that the area with 'predominantly high groundwater Fe' was a determinant of higher serum ferritin levels in NPNLW (standardized ß=0·19; P=0·03), SAC (standardized ß=0·22; P=0·01) and PSAC (standardized ß=0·20; P=0·03). This area also determined higher levels of Hb in PSAC (standardized ß=0·14; P=0·01). CONCLUSIONS: National prevalence of Fe deficiency in Bangladesh is low, contrary to the widely held assumption. High Fe level in groundwater is associated with higher Fe status (all populations) and higher Hb level (PSAC).