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1.
Am J Clin Nutr ; 112(5): 1328-1337, 2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-32844185

RESUMEN

BACKGROUND: Daily antenatal multiple micronutrient (MM) compared with iron folic acid (IFA) supplementation from early pregnancy improved birth outcomes and maternal micronutrient status in rural Bangladesh, but effects on newborn status are unknown. OBJECTIVE: We examined cord blood micronutrient biomarkers in relation to antenatal MM and IFA supplementation and maternal gestational micronutrient status in rural Bangladeshi newborns. DESIGN: In a double-blinded, cluster-randomized trial of antenatal IFA or MM (with the same IFA content), we analyzed cord blood plasma from 333 singleton births, and corresponding maternal plasma at 32.5 ± 2.6 wk of gestation, for ferritin (iron stores), folate, cobalamin (vitamin B-12), retinol (vitamin A), 25-hydroxyvitamin D [25(OH)D, vitamin D status], α-tocopherol (vitamin E), zinc, thyroglobulin, and free thyroxine (iodine status). Intervention effects and associations were determined using linear regression, exploring maternal status as a mediator of intervention effects on cord biomarkers. RESULTS: The MM intervention increased cord ferritin (mean: +12.4%; 95% CI: 1.3, 24.6%), 25(OH)D (mean: +14.7%; 95% CI: 4.8, 25.6%), and zinc (mean: +5.8%; 95% CI: 1.0, 10.8%). Cord folate (mean: +26.8%; 95% CI: 19.6, 34.5%), cobalamin (mean: +31.3%; 95% CI: 24.6, 38.3%), 25(OH)D (mean: +26.7%; 95% CI: 23.2, 30.3%), α-tocopherol (mean: +8.7%; 95% CI: 3.6, 13.7%), zinc (mean: +2.3%; 95% CI: 0.5, 4.2%), thyroglobulin (mean: +20.1%; 95% CI: 9.0, 32.2%) and thyroxine (mean: +1.5%; 95% CI: 0.0, 3.0%) increased per 1-SD increment in maternal status (all P < 0.05); ferritin and retinol changed by +2.0%; 95% CI: -8.9, 14.3%; P = 0.72; and +3.5%; 95% CI: -0.4, 7.3%; P = 0.07, respectively. Ferritin, folate, cobalamin, zinc, and thyroglobulin averaged 1.57-6.75 times higher and retinol, α-tocopherol, and 25(OH)D 0.30-0.84 times lower in cord than maternal plasma, suggesting preferential maternal-fetal transfer of iron, folate, cobalamin, and zinc; limited transfer of fat-soluble vitamins; and high fetal iodine demand. CONCLUSIONS: Antenatal MM supplementation increased newborn ferritin, 25(OH)D, and zinc, while maternal and newborn folate, vitamins B-12, D, and E, zinc, and iodine biomarkers were positively related. Despite limited effects of MM, better maternal micronutrient status was associated with improved micronutrient status of Bangladeshi newborns. This trial was registered at clinicaltrials.gov as NCT00860470.


Asunto(s)
Ácido Fólico/administración & dosificación , Hierro/administración & dosificación , Fenómenos Fisiologicos Nutricionales Maternos , Micronutrientes/administración & dosificación , Adulto , Biomarcadores/sangre , Análisis por Conglomerados , Suplementos Dietéticos , Método Doble Ciego , Femenino , Sangre Fetal , Ácido Fólico/sangre , Humanos , Recién Nacido , Embarazo , Población Rural , Adulto Joven
2.
J Nutr ; 150(7): 1924-1932, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32240304

RESUMEN

BACKGROUND: Complementary food supplementation enhances linear growth and may affect body composition in children. OBJECTIVE: We aimed to determine the effect of complementary food supplements provided from the age of 6 to 18 mo on fat-free mass (FFM) and fat mass (FM) gain among children in rural Bangladesh. METHODS: In an unblinded, cluster-randomized, controlled trial we tested the effects of 4 complementary food supplements for 1 y [chickpea, rice lentil, Plumpy'doz, and wheat-soy-blend++ (WSB++)] compared with no supplements on linear growth. Body composition was estimated using weight-length-based, age- and sex-specific equations at 6, 9, 12, 15, and 18 mo and postintervention aged 24 mo. Generalized estimating equations (GEEs) were applied to estimate the effect of each complementary food on mean FFM and FM from 9 to 18 and 24 mo compared with the control, adjusting for baseline measures. Sex interactions were also explored. RESULTS: In total, 3592 (65.9% of enrolled) children completed all anthropometric assessments. Estimated FFM and FM (mean ± SD) were 5.3 ± 0.6 kg and 1.4 ± 0.4 kg, respectively, at the age of 6 mo. Mean ± SE FFM and FM from 9 to 18 mo were 75.4 ± 14.0 g and 32.9 ± 7.1 g, and 61.0 ± 16.6 g and 30.0 ± 8.4 g, higher with Plumpy'doz and chickpea foods, respectively, than the control (P < 0.001). Estimated FFM was 41.5 ± 16.6 g higher in rice-lentil-fed versus control (P < 0.05) children. WSB++ had no impact on FFM or FM. A group-sex interaction (P < 0.1) was apparent with Plumpy'doz and rice-lentil foods, with girls involved in the intervention having higher estimated FFM and FM than control girls compared with no significant effect in boys. At 24 mo, FFM and FM remained higher only in girls eating Plumpy'doz compared with the controls (P < 0.01). CONCLUSIONS: In this randomized trial, supplementation effected small shifts in apparent body composition in rural Bangladeshi children. Where seen, FFM increments were twice that of FM, in proportion to these compartments, and more pronounced in girls. FFM increased in line with reported improvements in length. This trial was registered at clinicaltrials.gov as NCT01562379.


Asunto(s)
Desarrollo Infantil , Suplementos Dietéticos , Bangladesh , Composición Corporal , Análisis por Conglomerados , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Población Rural
3.
Matern Child Nutr ; 16(3): e12985, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32207581

RESUMEN

Undernutrition may affect fecundability, but few studies have quantified this relationship. In rural Bangladesh, where newlywed couples face strong pressures to become pregnant, we assessed fecundability, estimated by time to pregnancy (TTP), and its association with preconceptional thinness among nulligravid, newlywed female adolescents. During 2001-2002, 5,516 newlywed women aged 12-19 years participated in a home-based, 5-weekly surveillance system for 5-6 years to enrol pregnant women into an antenatal vitamin A or ß-carotene supplementation trial. Thinness was defined as a left mid-upper arm circumference (MUAC) ≤21.5 versus >21.5 cm. At each visit, staff obtained a monthly history of menstruation. Report of amenorrhea prompted a human chorionic gonadotropin urine test to confirm pregnancy. We derived hazard ratios (with 95% confidence intervals [CI]) for pregnancy and Kaplan-Meier curves for TTP. Ages of women at marriage and pregnancy detection (mean ± standard deviation) were 15.3 ± 1.9 and 17.0 ± 1.9 years, respectively. A total of 82.7% of thinner and 87.3% of better nourished women became pregnant. The unadjusted and multivariable relative hazard of ever becoming pregnant was 0.84 (95% CI [0.78, 0.89]) and 0.86 (95% CI [0.81, 0.92]), respectively, and TTP was 12 weeks longer (median [95% CI]: 63 [58-68] vs. 51 [49-54]) in women whose MUAC was ≤21.5 versus >21.5 cm. In rural Bangladesh, thin adolescent newlywed girls have a lower probability of becoming pregnant and experience a longer time to pregnancy.


Asunto(s)
Matrimonio , Delgadez/fisiopatología , Tiempo para Quedar Embarazada/fisiología , Adolescente , Adulto , Bangladesh , Niño , Femenino , Fertilidad/fisiología , Humanos , Embarazo , Estudios Prospectivos , Población Rural/estadística & datos numéricos , Adulto Joven
4.
J Dev Orig Health Dis ; 11(2): 127-135, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31475652

RESUMEN

The thymus undergoes a critical period of growth and development early in gestation and, by mid-gestation, immature thymocytes are subject to positive and negative selection. Exposure to undernutrition during these periods may permanently affect phenotype. We measured thymulin concentrations, as a proxy for thymic size and function, in children (n = 290; aged 9-13 years) born to participants in a cluster-randomized trial of maternal vitamin A or ß-carotene supplementation in rural Nepal (1994-1997). The geometric mean (95% confidence interval) thymulin concentration was 1.37 ng/ml (1.27, 1.47). A multivariate model of early-life exposures revealed a positive association with gestational age at delivery (ß = 0.02; P = 0.05) and higher concentrations among children born to ß-carotene-supplemented mothers (ß = 0.19; P < 0.05). At ∼9-12 years of age, thymulin was positively associated with all anthropometric measures, with height retained in our multivariate model (ß = 0.02; P < 0.001). There was significant seasonal variation: concentrations tended to be lower pre-monsoon (ß = -0.13; P = 0.15), during the monsoon (ß = -0.22; P = 0.04), and pre-harvest (ß = -0.34; P = 0.01), relative to the post-harvest season. All early-life associations, except supplementation, were mediated in part by nutritional status at follow-up. Our findings underscore the known sensitivity of the thymus to nutrition, including potentially lasting effects of early nutritional exposures. The relevance of these findings to later disease risk remains to be explored, particularly given the role of thymulin in the neuroendocrine regulation of inflammation.


Asunto(s)
Desnutrición/dietoterapia , Efectos Tardíos de la Exposición Prenatal/epidemiología , Factor Tímico Circulante/análisis , Timo/fisiopatología , Adolescente , Niño , Desarrollo Infantil , Preescolar , Suplementos Dietéticos , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Desnutrición/fisiopatología , Fenómenos Fisiologicos Nutricionales Maternos , Nepal/epidemiología , Estado Nutricional/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Efectos Tardíos de la Exposición Prenatal/prevención & control , Factores de Riesgo , Población Rural/estadística & datos numéricos , Estaciones del Año , Factor Tímico Circulante/metabolismo , Timo/crecimiento & desarrollo , Resultado del Tratamiento , Vitamina A/administración & dosificación , Adulto Joven , beta Caroteno/administración & dosificación
5.
Am J Clin Nutr ; 110(4): 1015-1025, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31565748

RESUMEN

BACKGROUND: Environmental enteric dysfunction (EED) is thought to increase the risk of micronutrient deficiencies, but few studies adjust for dietary intakes and systemic inflammation. OBJECTIVE: We tested whether EED is associated with micronutrient deficiency risk independent of diet and systemic inflammation, and whether it mediates the relation between intake and micronutrient status. METHODS: Using data from 1283 children in the MAL-ED (Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health) birth cohort we evaluated the risk of anemia, low retinol, zinc, and ferritin, and high transferrin receptor (TfR) at 15 mo. We characterized gut inflammation and permeability by myeloperoxidase (MPO), neopterin (NEO), and α-1-antitrypsin (AAT) concentrations from asymptomatic fecal samples averaged from 9 to 15 mo, and averaged the lactulose:mannitol ratio z-score (LMZ) at 9 and 15 mo. Nutrient intakes from complementary foods were quantified monthly from 9 to 15 mo and densities were averaged for analyses. α-1-Acid glycoprotein at 15 mo characterized systemic inflammation. Relations between variables were modeled using a Bayesian network. RESULTS: A greater risk of anemia was associated with LMZ [1.15 (95% CI: 1.01, 1.31)] and MPO [1.16 (1.01, 1.34)]. A greater risk of low ferritin was associated with AAT [1.19 (1.03, 1.37)] and NEO [1.22 (1.04, 1.44)]. A greater risk of low retinol was associated with LMZ [1.24 (1.08, 1.45)]. However, MPO was associated with a lower risk of high transferrin receptor [0.86 (0.74, 0.98)], NEO with a lower risk of low retinol [0.75 (0.62, 0.89)], and AAT with a lower risk of low plasma zinc [0.83 (0.70, 0.99)]. Greater nutrient intake densities (vitamins A and B6, calcium, protein, and zinc) were negatively associated with EED. Inverse associations between nutrient densities and micronutrient deficiency largely disappeared after adjustment for EED, suggesting that EED mediates these associations. CONCLUSIONS: EED is independently associated with an increased risk of low ferritin, low retinol, and anemia. Greater nutrient density from complementary foods may reduce EED, and the control of micronutrient deficiencies may require control of EED.


Asunto(s)
Alimentos Infantiles , Fenómenos Fisiológicos Nutricionales del Lactante , Inflamación/patología , Intestinos/fisiología , Micronutrientes/sangre , Nutrientes/metabolismo , Teorema de Bayes , Biomarcadores/análisis , Biomarcadores/sangre , Estudios de Cohortes , Heces/química , Humanos , Lactante , Inflamación/metabolismo , Enfermedades Intestinales , Intestinos/efectos de los fármacos , Estado Nutricional , Permeabilidad
6.
Epidemiol Infect ; 147: e258, 2019 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-31469064

RESUMEN

Maternal systemic inflammation during pregnancy may restrict embryo-fetal growth, but the extent of this effect remains poorly established in undernourished populations. In a cohort of 653 maternal-newborn dyads participating in a multi-armed, micronutrient supplementation trial in southern Nepal, we investigated associations between maternal inflammation, assessed by serum α1-acid glycoprotein and C-reactive protein, in the first and third trimesters of pregnancy, and newborn weight, length and head and chest circumferences. Median (IQR) maternal concentrations in α1-acid glycoprotein and C-reactive protein in the first and third trimesters were 0.65 (0.53-0.76) and 0.40 (0.33-0.50) g/l, and 0.56 (0.25-1.54) and 1.07 (0.43-2.32) mg/l, respectively. α1-acid glycoprotein was inversely associated with birth size: weight, length, head circumference and chest circumference were lower by 116 g (P = 2.3 × 10-6), and 0.45 (P = 3.1 × 10-5), 0.18 (P = 0.0191) and 0.48 (P = 1.7 × 10-7) cm, respectively, per 50% increase in α1-acid glycoprotein averaged across both trimesters. Adjustment for maternal age, parity, gestational age, nutritional and socio-economic status and daily micronutrient supplementation failed to alter any association. Serum C-reactive protein concentration was largely unassociated with newborn size. In rural Nepal, birth size was inversely associated with low-grade, chronic inflammation during pregnancy as indicated by serum α1-acid glycoprotein.


Asunto(s)
Retardo del Crecimiento Fetal/epidemiología , Inflamación/complicaciones , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Antropometría , Proteína C-Reactiva/análisis , Ensayos Clínicos como Asunto , Femenino , Humanos , Recién Nacido , Nepal/epidemiología , Orosomucoide/análisis , Embarazo , Población Rural , Adulto Joven
7.
J Nutr ; 149(7): 1260-1270, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31006806

RESUMEN

BACKGROUND: Antenatal multiple micronutrient (MM) supplementation improves birth outcomes relative to iron-folic acid (IFA) in developing countries, but limited data exist on its impact on pregnancy micronutrient status. OBJECTIVE: We assessed the efficacy of a daily MM (15 nutrients) compared with IFA supplement, each providing approximately 1 RDA of nutrients and given beginning at pregnancy ascertainment, on late pregnancy micronutrient status of women in rural Bangladesh. Secondarily, we explored other contributors to pregnancy micronutrient status. METHODS: Within a double-masked trial (JiVitA-3) among 44,500 pregnant women, micronutrient status indicators were assessed in n = 1526 women, allocated by cluster to receive daily MM (n = 749) or IFA (n = 777), at 10 wk (baseline: before supplementation) and 32 wk (during supplementation) gestation. Efficacy of MM supplementation on micronutrient status indicators at 32 wk was assessed, controlling for baseline status and other covariates (e.g., inflammation and season), in regression models. RESULTS: Baseline status was comparable by intervention. Prevalence of deficiency among all participants was as follows: anemia, 20.6%; iron by ferritin, 4.0%; iron by transferrin receptor, 4.7%; folate, 2.5%; vitamin B-12, 35.4%; vitamin A, 6.7%; vitamin E, 57.7%; vitamin D, 64.0%; zinc, 13.4%; and iodine, 2.6%. At 32 wk gestation, vitamin B-12, A, and D and zinc status indicators were 3.7-13.7% higher, and ferritin, γ-tocopherol, and thyroglobulin indicators were 8.7-16.6% lower, for the MM group compared with the IFA group, with a 15-38% lower prevalence of deficiencies of vitamins B-12, A, and D and zinc (all P < 0.05). However, indicators typically suggested worsening status during pregnancy, even with supplementation, and baseline status or other covariates were more strongly associated with late pregnancy indicators than was MM supplementation. CONCLUSIONS: Rural Bangladeshi women commonly entered pregnancy deficient in micronutrients other than iron and folic acid. Supplementation with MM improved micronutrient status, although deficiencies persisted. Preconception supplementation or higher nutrient doses may be warranted to support nutritional demands of pregnancy in undernourished populations. This trial was registered at clinicaltrials.gov as NCT00860470.


Asunto(s)
Suplementos Dietéticos , Ácido Fólico/administración & dosificación , Hierro/administración & dosificación , Micronutrientes/administración & dosificación , Población Rural , Bangladesh , Femenino , Humanos , Embarazo
8.
Eur J Clin Nutr ; 72(2): 301-303, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29321687

RESUMEN

Biofortified maize, designed as an intervention strategy to prevent vitamin A deficiency, can provide upwards of 15 µg ß-carotene per g dry weight. Some varieties also have elevated concentrations of other carotenoids. We conducted a cluster randomized, controlled feeding trial in rural Zambia to test the impact of daily consumption of biofortified maize over a 6-month period on vitamin A status. Serum concentrations of retinol and carotenoids were assessed by high-performance liquid chromatography. Data on circulating carotenoids by intervention group in 679 children are reported here. As previously shown, consumption of this ß-carotene-rich maize significantly improved serum ß-carotene concentrations (0.273 vs. 0.147 µmol/L, p < 0.001, in this subset of children). Here we show significant increases in α-carotene, ß-cryptoxanthin, and zeaxanthin (p < 0.001). There was no impact on lutein or lycopene concentrations. Consumption of biofortified maize can have broader implications beyond the control of vitamin A deficiency (Trial registration: NCT01695148).


Asunto(s)
Carotenoides/sangre , Dieta , Alimentos Fortificados , Zea mays , beta-Criptoxantina/sangre , Niño , Preescolar , Femenino , Trastornos del Crecimiento/epidemiología , Humanos , Luteína/sangre , Masculino , Estado Nutricional , Factores Socioeconómicos , Delgadez/epidemiología , Zambia/epidemiología , Zeaxantinas/sangre , beta Caroteno/sangre
9.
J Nutr ; 147(8): 1531-1536, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28701387

RESUMEN

Background: Higher iron stores, defined by serum ferritin (SF) concentration, may increase malaria risk.Objective: We evaluated the association between SF assessed during low malaria season and the risk of malaria during high malaria season, controlling for inflammation.Methods: Data for this prospective study were collected from children aged 4-8 y (n = 745) participating in a biofortified maize efficacy trial in rural Zambia. All malaria cases were treated at baseline (September 2012). We used baseline SF and malaria status indicated by positive microscopy at endline (March 2013) to define exposure and outcome, respectively. Iron status was defined as deficient (corrected or uncorrected SF <12 or <15 µg/L, depending on age <5 or ≥5 y, respectively), moderate (<75 µg/L, excluding deficient), or high (≥75 µg/L). We used a modified Poisson regression to model the risk of malaria in the high transmission seasons (endline) as a function of iron status assessed in the low malaria seasons (baseline).Results: We observed an age-dependent, positive dose-response association between ferritin in the low malaria season and malaria incidence during the high malaria season in younger children. In children aged <6 y (but not older children), we observed a relative increase in malaria risk in the moderate iron status [incidence rate ratio (IRR) with SF: 1.56; 95% CI: 0.64, 3.86; IRR with inflammation-corrected SF: 1.92; 95% CI: 0.75, 4.93] and high iron status (IRR with SF: 2.66; 95% CI: 1.10, 6.43; or IRR with corrected SF: 2.93; 95% CI: 1.17, 7.33) categories compared with the deficient iron status category. The relative increase in malaria risk for children with high iron status was statistically significant only among those with a concurrently normal serum soluble transferrin receptor concentration (<8.3 mg/L; IRR: 1.97; 95% CI: 1.20, 7.37).Conclusions: Iron adequacy in 4- to 8-y-old children in rural Zambia was associated with increased malaria risk. Our findings underscore the need to integrate iron interventions with malaria control programs. This trial was registered at clinicaltrials.gov as NCT01695148.


Asunto(s)
Hierro/sangre , Malaria/etiología , Estado Nutricional , Estaciones del Año , Factores de Edad , Anemia Ferropénica/sangre , Preescolar , Femenino , Ferritinas/sangre , Alimentos Fortificados , Humanos , Inflamación/sangre , Malaria/sangre , Malaria/transmisión , Masculino , Estudios Prospectivos , Factores de Riesgo , Población Rural , Zambia
10.
J Nutr ; 147(3): 304-313, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28148680

RESUMEN

Background: Malnutrition affects body growth, size, and composition of children. Yet, few functional biomarkers are known to be associated with childhood morphology.Objective: This cross-sectional study examined associations of anthropometric indicators of height, musculature, and fat mass with plasma proteins by using proteomics in a population cohort of school-aged Nepalese children.Methods: Height, weight, midupper arm circumference (MUAC), triceps and subscapular skinfolds, upper arm muscle area (AMA), and arm fat area (AFA) were assessed in 500 children 6-8 y of age. Height-for-age z scores (HAZs), weight-for-age z scores (WAZs), and body mass index-for-age z scores (BAZs) were derived from the WHO growth reference. Relative protein abundance was quantified by using tandem mass spectrometry. Protein-anthropometry associations were evaluated by linear mixed-effects models and identified as having a false discovery rate (q) <5%.Results: Among 982 proteins, 1, 10, 14, and 17 proteins were associated with BAZ, HAZ, MUAC, and AMA, respectively (q < 0.05). Insulin-like growth factor (IGF)-I, 2 IGF-binding proteins, and carnosinase-1 were associated with both HAZ and AMA. Proteins involved in nutrient transport, activation of innate immunity, and bone mineralization were associated with HAZ. Several extracellular matrix proteins were positively associated with AMA alone. The proteomes of MUAC and AMA substantially overlapped, whereas no proteins were associated with AFA or triceps and subscapular skinfolds. Myosin light-chain kinase, possibly reflecting leakage from muscle, was inversely associated with BAZ. The proteome of WAZ was the largest (n = 33) and most comprehensive, including proteins involved in neural development and oxidative stress response, among others.Conclusions: Plasma proteomics confirmed known biomarkers of childhood growth and revealed novel proteins associated with lean mass in chronically undernourished children. Identified proteins may serve as candidates for assessing growth and nutritional status of children in similar undernourished settings. The antenatal micronutrient supplementation trial yielding the study cohort of children was registered at clinicaltrials.gov as NCT00115271.


Asunto(s)
Antropometría , Proteínas Sanguíneas/química , Trastornos de la Nutrición del Niño/sangre , Discapacidades del Desarrollo/epidemiología , Proteoma/química , Proteínas Sanguíneas/metabolismo , Niño , Femenino , Humanos , Masculino , Músculo Esquelético , Nepal/epidemiología , Estado Nutricional , Delgadez
11.
J Nutr ; 146(12): 2551-2558, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27798345

RESUMEN

BACKGROUND: Impaired dark adaptation is an early functional indicator of vitamin A deficiency that may be prevented by regular dietary intake of foods containing provitamin A carotenoids. OBJECTIVE: We tested the impact of provitamin A carotenoid-biofortified maize consumption (∼15 µg ß-carotene/g) on dark adaptation in Zambian children. METHODS: We used a cluster-randomized trial of children aged 4-8 y (n = 1024) in Mkushi District, Zambia, and compared the regular consumption (2 meals/d, 6 d/wk for 6 mo) of biofortified orange maize (OM) to white maize (WM). The primary outcome was the serum retinol response. In a random sample (n = 542), we used a digital pupillometer to test pre- and postintervention responses to graded light stimuli (-2.9 to 0.1 log cd/m2) in a dark-adapted state. RESULTS: At baseline, 11.7% of the children had serum retinol <0.7 µmol/L, 14.4% had impaired dark adaptation (pupillary threshold ≥ -1.11 log cd/m2), and 2.3% had night blindness. The mean ± SD pupillary responsiveness to light stimuli was poorer at baseline in the OM group (16.1% ± 6.6%) than the WM group (18.1% ± 6.4%) (P = 0.02) but did not differ at follow-up (OM: 17.6% ± 6.5%; WM: 18.3% ± 6.5%). Among children with serum retinol <1.05 µmol/L at baseline, there was greater improvement in pupillary responsiveness in the OM group (2.2%; 95% CI: 0.1%, 4.3%) than the WM group (0.2%; 95% CI: -1.1%, 1.5%; P = 0.01), but there were no differences in children with adequate baseline status. We found no effect of treatment on pupillary threshold or night blindness. CONCLUSIONS: The regular consumption of provitamin A carotenoid-biofortified maize increased pupillary responsiveness among children with marginal or deficient vitamin A status, providing evidence of a functional benefit to consuming this biofortified crop. This trial was registered at clinicaltrials.gov as NCT01695148.


Asunto(s)
Alimentos Fortificados , Provitaminas , Reflejo Pupilar , Deficiencia de Vitamina A/dietoterapia , Zea mays , beta Caroteno/administración & dosificación , Niño , Preescolar , Dieta , Femenino , Humanos , Masculino , Comidas , Estado Nutricional , Vitamina A , Deficiencia de Vitamina A/epidemiología , Zambia/epidemiología , beta Caroteno/farmacología
12.
Am J Clin Nutr ; 104(1): 181-90, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27169838

RESUMEN

BACKGROUND: Vitamin A deficiency remains a nutritional concern in sub-Saharan Africa. Conventionally bred maize hybrids with high provitamin A carotenoid concentrations may have the potential to improve vitamin A status in maize-consuming populations. OBJECTIVE: We evaluated the efficacy of regular provitamin A carotenoid-biofortified "orange" maizemeal (∼15 µg ß-carotene/g) consumption in improving vitamin A status and reducing vitamin A deficiency in children. DESIGN: This was a cluster-randomized controlled trial in the rural farming district of Mkushi, Zambia. All 4- to 8-y-old children in an ∼400-km(2) area were identified and grouped by proximity into clusters of ∼15-25 children. We randomly assigned clusters to 1) orange maizemeal (n = 25), 2) white maizemeal (n = 25), or 3) a parallel, nonintervention group (n = 14). Children in intervention clusters (n = 1024) received 200 g maizemeal for 6 d/wk over 6 mo; the maizemeal was prepared according to standardized recipes and served in cluster-level kitchens. Staff recorded attendance and leftovers. We collected venous blood before and after the intervention to measure serum retinol, ß-carotene, C-reactive protein, and α1-acid glycoprotein. RESULTS: Intervention groups were comparable at baseline, and vitamin A status was better than anticipated (12.1% deficient on the basis of serum retinol <0.7 µmol/L). Although attendance at meals did not differ (85%), median daily maize intake was higher in white (154 g/d) than in orange (142 g/d) maizemeal clusters. At follow-up, mean serum ß-carotene was 0.14 µmol/L (95% CI: 0.09, 0.20 µmol/L) higher in orange maizemeal clusters (P < 0.001), but mean serum retinol (1.00 ± 0.33 µmol/L overall) and deficiency prevalence (17.1% overall) did not differ between arms. CONCLUSION: In this marginally nourished population, regular biofortified maizemeal consumption increased serum ß-carotene concentrations but did not improve serum retinol. This trial was registered at clinicaltrials.gov as NCT01695148.


Asunto(s)
Dieta , Grano Comestible , Alimentos Fortificados , Provitaminas/farmacología , Vitamina A/sangre , Zea mays , beta Caroteno/farmacología , Proteína C-Reactiva/metabolismo , Niño , Preescolar , Femenino , Humanos , Masculino , Estado Nutricional , Provitaminas/sangre , Provitaminas/uso terapéutico , Población Rural , Resultado del Tratamiento , Deficiencia de Vitamina A/sangre , Deficiencia de Vitamina A/dietoterapia , Deficiencia de Vitamina A/tratamiento farmacológico , Zambia , beta Caroteno/sangre , beta Caroteno/uso terapéutico
13.
Nat Rev Endocrinol ; 12(5): 274-89, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27032981

RESUMEN

Micronutrients, vitamins and minerals accessible from the diet, are essential for biologic activity. Micronutrient status varies widely throughout pregnancy and across populations. Women in low-income countries often enter pregnancy malnourished, and the demands of gestation can exacerbate micronutrient deficiencies with health consequences for the fetus. Examples of efficacious single micronutrient interventions include folic acid to prevent neural tube defects, iodine to prevent cretinism, zinc to reduce risk of preterm birth, and iron to reduce the risk of low birth weight. Folic acid and vitamin D might also increase birth weight. While extensive mechanistic and association research links multiple antenatal micronutrients with plausible materno-fetal health advantages, hypothesized benefits have often been absent, minimal or unexpected in trials. These findings suggest a role for population context in determining health responses and filling extensive gaps in knowledge. Multiple micronutrient supplements reduce the risks of being born with low birth weight, small for gestational age or stillborn in undernourished settings, and justify micronutrient interventions with antenatal care. Measurable health effects of gestational micronutrient exposure might persist into childhood but few data exists on potential long-term benefits. In this Review, we discuss micronutrient intake recommendations, risks and consequences of deficiencies, and the effects of interventions with a particular emphasis on offspring.


Asunto(s)
Micronutrientes/deficiencia , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/prevención & control , Adulto , Dieta , Femenino , Humanos , Estado Nutricional , Embarazo , Resultado del Embarazo
14.
J Nutr ; 145(12): 2646-56, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26446483

RESUMEN

BACKGROUND: The term vitamin E describes a family of 8 vitamers, 1 of which is α-tocopherol, that is essential for human health. Vitamin E status remains largely unknown in low-income countries because of the complexity and cost of measurement. Quantitative proteomics may offer an approach for identifying plasma proteins for assessing vitamin E status in these populations. OBJECTIVE: To improve options for vitamin E status assessment, we sought to detect and quantify a set of plasma proteins associated with α- and γ-tocopherol concentrations in a cohort of 500 rural Nepalese children aged 6-8 y and, based on nutrient-protein associations, to predict the prevalence of vitamin E deficiency (α-tocopherol <12 µmol/L). METHODS: Study children were born to mothers enrolled in an earlier antenatal micronutrient trial in Sarlahi District, Nepal. Plasma α- and γ-tocopherol concentrations were measured by high-performance liquid chromatography. Plasma aliquots were depleted of 6 high-abundance proteins, digested with trypsin, labeled with isobaric mass tags, and assessed for relative protein abundance by tandem mass spectrometry. Linear mixed-effects models were used to evaluate the association between α-tocopherol status and relative protein abundance and to predict deficiency. RESULTS: We quantified 982 plasma proteins in >10% of all child samples, of which 119 correlated with α-tocopherol (false discovery rate, q < 0.10). Proteins were primarily involved in lipid transport, coagulation, repair, innate host defenses, neural function, and homeostasis. Six proteins [apolipoprotein (apo)C-III; apoB; pyruvate kinase, muscle; forkhead box 04; unc5 homolog C; and regulator of G-protein signaling 8] explained 71% of the variability in plasma α-tocopherol, predicting an in-sample population prevalence of vitamin E deficiency of 51.4% (95% CI: 46.4%, 56.3%) compared with a measured prevalence of 54.8%. Plasma γ-tocopherol was associated with 12 proteins (q < 0.10), 2 of which (apoC-III and Misato 1) explained 20% of its variability. CONCLUSIONS: In this undernourished population of children in South Asia, quantitative proteomics identified a large plasma α-tocopherome from which 6 proteins predicted the prevalence of vitamin E deficiency. The findings illustrate that protein biomarkers, once absolutely quantified, can potentially predict micronutrient deficiencies in populations. The maternal micronutrient supplementation trial from which data were derived as a follow-up activity was registered with clinicaltrials.gov as NCT00115271.


Asunto(s)
Biomarcadores/sangre , Proteínas Sanguíneas/análisis , Proteómica , Deficiencia de Vitamina E/sangre , alfa-Tocoferol/sangre , Niño , Dieta , Suplementos Dietéticos , Humanos , Desnutrición/sangre , Micronutrientes/deficiencia , Nepal/epidemiología , Estado Nutricional , Deficiencia de Vitamina E/epidemiología , gamma-Tocoferol/sangre
15.
PLoS One ; 10(10): e0137269, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26431336

RESUMEN

UNLABELLED: Prenatal multiple micronutrient (MM) supplementation improves birth weight through increased fetal growth and gestational age, but whether maternal or fetal growth factors are involved is unclear. Our objective was to examine the effect of prenatal MM supplementation on intrauterine growth factors and the associations between growth factors and birth outcomes in a rural setting in Bangladesh. In a double-blind, cluster-randomized, controlled trial of MM vs. iron and folic acid (IFA) supplementation, we measured placental growth hormone (PGH) at 10 weeks and PGH and human placental lactogen (hPL) at 32 weeks gestation in maternal plasma (n = 396) and insulin, insulin-like growth factor-1 (IGF-1), and IGF binding protein-1 (IGFBP-1) in cord plasma (n = 325). Birth size and gestational age were also assessed. Early pregnancy mean (SD) BMI was 19.5 (2.4) kg/m2 and birth weight was 2.68 (0.41) kg. There was no effect of MM on concentrations of maternal hPL or PGH, or cord insulin, IGF-1, or IGFBP-1. However, among pregnancies of female offspring, hPL concentration was higher by 1.1 mg/L in the third trimester (95% CI: 0.2, 2.0 mg/L; p = 0.09 for interaction); and among women with height <145 cm, insulin was higher by 59% (95% CI: 3, 115%; p = 0.05 for interaction) in the MM vs. IFA group. Maternal hPL and cord blood insulin and IGF-1 were positively, and IGFBP-1 was negatively, associated with birth weight z score and other measures of birth size (all p<0.05). IGF-1 was inversely associated with gestational age (p<0.05), but other growth factors were not associated with gestational age or preterm birth. Prenatal MM supplementation had no overall impact on intrauterine growth factors. MM supplementation altered some growth factors differentially by maternal early pregnancy nutritional status and sex of the offspring, but this should be examined in other studies. TRIAL REGISTRATION: ClinicalTrials.gov NCT00860470.


Asunto(s)
Suplementos Dietéticos , Feto/metabolismo , Péptidos y Proteínas de Señalización Intercelular/sangre , Atención Prenatal , Población Rural , Adolescente , Adulto , Bangladesh , Análisis por Conglomerados , Método Doble Ciego , Femenino , Humanos , Embarazo , Adulto Joven
16.
Nutrition ; 31(6): 813-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25933488

RESUMEN

OBJECTIVE: B1a lymphocytes-which constitutively produce most natural antibodies (NAb)-arise from an early wave of progenitors unique to fetal life. Vitamin A regulates early lymphopoiesis. In animals, deficiency during this critical period compromises B1 cell populations. The aim of this study was to investigate the effect of maternal supplementation with vitamin A or ß-carotene from preconception through lactation on NAb concentrations of offspring. METHODS: Participants (N = 290) were born to participants of a cluster-randomized, placebo-controlled trial of weekly maternal vitamin A or ß-carotene supplementation (7000 µg retinol equivalents) conducted in Sarlahi, Nepal (1994-1997) and assessed at ages 9 to 13 y (2006-2008). Serum retinol was measured by reversed-phase high-performance liquid chromatography at mid-pregnancy and 3 mo of age. Enzyme-linked immunosorbent assay (ELISA) was used to measure children's plasma NAb concentrations at 9 to 13 y. RESULTS: Unadjusted geometric mean concentrations were 20.08 U/mL (95% confidence interval [CI], 17.82-22.64) in the vitamin A group compared with 17.64 U/mL (95% CI, 15.70-19.81) and 15.96 U/mL (95% CI, 13.43-18.96) in the ß-carotene and placebo groups (P = 0.07), respectively. After adjustment, maternal vitamin A supplementation was associated with a 0.39 SD increase in NAb concentrations (P = 0.02). The effect was mediated by infant serum retinol in our statistical models. Although girls had 1.4-fold higher NAb concentrations (P < 0.001), sex did not modify the vitamin A effect. CONCLUSIONS: In an undernourished population, maternal vitamin A supplementation enhanced NAb concentrations of preadolescent children. We posit that this was due to a greater allotment of B1a precursors during fetal life and a sustained higher count of NAb-secreting B1a cells.


Asunto(s)
Anticuerpos/sangre , Suplementos Dietéticos , Linfopoyesis/efectos de los fármacos , Atención Prenatal , Deficiencia de Vitamina A/tratamiento farmacológico , Vitamina A/farmacología , Vitaminas/farmacología , Adulto , Linfocitos B/fisiología , Niño , Femenino , Humanos , Lactante , Masculino , Desnutrición/tratamiento farmacológico , Desnutrición/inmunología , Nepal , Embarazo , Complicaciones del Embarazo , Fenómenos Fisiologicos de la Nutrición Prenatal , Población Rural , Vitamina A/sangre , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/inmunología , Vitaminas/sangre , Vitaminas/uso terapéutico , Adulto Joven , beta Caroteno/sangre , beta Caroteno/farmacología , beta Caroteno/uso terapéutico
17.
Asia Pac J Clin Nutr ; 24(1): 128-37, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25740751

RESUMEN

Pregnancy exacerbates vitamin A (VA) deficiency and anaemia among women in developing countries. Improving circulating haemoglobin (Hb) requires erythrocyte production and availability of iron. Insulin-like growth factor- 1 (IGF-1) functions in erythropoiesis, but its association with VA status and pregnancy-associated anaemia has not been studied. The aim of this study was to examine the relationship between serum retinol, IGF-1, and Hb among pregnant women in extant samples collected during a placebo-controlled trial of VA and beta-carotene (BC) supplementation in rural Nepal conducted from 1994 to 1997. Mid-pregnancy serum IGF-1 was measured in serum from n=589 randomly selected women of n=1186 in whom anthropometric, VA (retinol) and iron (Hb, erythrocyte zinc protoporphyrin (ZP), and ferritin) status data were available. Associations of IGF-1 with retinol, Hb or anaemia, and iron status were determined using multiple linear and logistic regression. Path analysis was used to explore the role of IGF-1 as a mediator between retinol and Hb, accounting for iron status. A 2.6 g/L increase in IGF-1 was observed per 0.1 mol/L increment in retinol (p<0.0001). Hb increased with each quartile of IGF-1, and odds of anaemia declined 68.8% from the 1st to 4th quartile. Improved iron status indicators explained only 29.1% of the association between IGF-1 and Hb, while IGF-1 explained 25.6% of the association between retinol and Hb. Increasing IGF-1 was likely one mechanism by which retinol improved circulating Hb in pregnant women of rural Nepal, although IGF-1 worked primarily through pathways independent of improved iron status indicators, perhaps by stimulating erythrocyte production.


Asunto(s)
Hemoglobinas/análisis , Factor I del Crecimiento Similar a la Insulina/fisiología , Complicaciones del Embarazo/sangre , Deficiencia de Vitamina A/sangre , Adulto , Anemia/sangre , Anemia/complicaciones , Suplementos Dietéticos , Método Doble Ciego , Eritropoyesis/fisiología , Femenino , Ferritinas/sangre , Edad Gestacional , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Hierro/sangre , Hierro de la Dieta/administración & dosificación , Nepal , Estado Nutricional , Embarazo , Población Rural , Vitamina A/administración & dosificación , Vitamina A/sangre , Adulto Joven , beta Caroteno/administración & dosificación
18.
JAMA ; 312(24): 2649-58, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25536256

RESUMEN

IMPORTANCE: Maternal micronutrient deficiencies may adversely affect fetal and infant health, yet there is insufficient evidence of effects on these outcomes to guide antenatal micronutrient supplementation in South Asia. OBJECTIVE: To assess effects of antenatal multiple micronutrient vs iron-folic acid supplementation on 6-month infant mortality and adverse birth outcomes. DESIGN, SETTING, AND PARTICIPANTS: Cluster randomized, double-masked trial in Bangladesh, with pregnancy surveillance starting December 4, 2007, and recruitment on January 11, 2008. Six-month infant follow-up ended August 30, 2012. Surveillance included 127,282 women; 44,567 became pregnant and were included in the analysis and delivered 28,516 live-born infants. Median gestation at enrollment was 9 weeks (interquartile range, 7-12). INTERVENTIONS: Women were provided supplements containing 15 micronutrients or iron-folic acid alone, taken daily from early pregnancy to 12 weeks postpartum. MAIN OUTCOMES AND MEASURES: The primary outcome was all-cause infant mortality through 6 months (180 days). Prespecified secondary outcomes in this analysis included stillbirth, preterm birth (<37 weeks), and low birth weight (<2500 g). To maintain overall significance of α = .05, a Bonferroni-corrected α = .01 was calculated to evaluate statistical significance of primary and 4 secondary risk outcomes (.05/5). RESULTS: Among the 22,405 pregnancies in the multiple micronutrient group and the 22,162 pregnancies in the iron-folic acid group, there were 14,374 and 14,142 live-born infants, respectively, included in the analysis. At 6 months, multiple micronutrients did not significantly reduce infant mortality; there were 764 deaths (54.0 per 1000 live births) in the iron-folic acid group and 741 deaths (51.6 per 1000 live births) in the multiple micronutrient group (relative risk [RR], 0.95; 95% CI, 0.86-1.06). Multiple micronutrient supplementation resulted in a non-statistically significant reduction in stillbirths (43.1 vs 48.2 per 1000 births; RR, 0.89; 95% CI, 0.81-0.99; P = .02) and significant reductions in preterm births (18.6 vs 21.8 per 100 live births; RR, 0.85; 95% CI, 0.80-0.91; P < .001) and low birth weight (40.2 vs 45.7 per 100 live births; RR, 0.88; 95% CI, 0.85-0.91; P < .001). CONCLUSIONS AND RELEVANCE: In Bangladesh, antenatal multiple micronutrient compared with iron-folic acid supplementation did not reduce all-cause infant mortality to age 6 months but resulted in a non-statistically significant reduction in stillbirths and significant reductions in preterm births and low birth weight. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00860470.


Asunto(s)
Enfermedades Carenciales/tratamiento farmacológico , Suplementos Dietéticos , Ácido Fólico/uso terapéutico , Micronutrientes/uso terapéutico , Complicaciones del Embarazo/tratamiento farmacológico , Atención Prenatal , Administración Oral , Adulto , Bangladesh , Enfermedades Carenciales/complicaciones , Femenino , Humanos , Lactante , Mortalidad Infantil , Recién Nacido de Bajo Peso , Recién Nacido , Hierro , Embarazo , Nacimiento Prematuro , Población Rural , Mortinato , Adulto Joven
19.
Food Chem Toxicol ; 74: 184-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25308602

RESUMEN

Aflatoxin B1 is a potent carcinogen, occurring from mold growth that contaminates staple grains in hot, humid environments. In this investigation, aflatoxin B1-lysine albumin biomarkers were measured by mass spectrometry in rural South Asian women, during the first and third trimester of pregnancy, and their children at birth and at two years of age. These subjects participated in randomized community trials of antenatal micronutrient supplementation in Sarlahi District, southern Nepal and Gaibandha District in northwestern Bangladesh. Findings from the Nepal samples demonstrated exposure to aflatoxin, with 94% detectable samples ranging from 0.45 to 2939.30 pg aflatoxin B1-lysine/mg albumin during pregnancy. In the Bangladesh samples the range was 1.56 to 63.22 pg aflatoxin B1-lysine/mg albumin in the first trimester, 3.37 to 72.8 pg aflatoxin B1-lysine/mg albumin in the third trimester, 4.62 to 76.69 pg aflatoxin B1-lysine/mg albumin at birth and 3.88 to 81.44 pg aflatoxin B1-lysine/mg albumin at age two years. Aflatoxin B1-lysine adducts in cord blood samples demonstrated that the fetus had the capacity to convert aflatoxin into toxicologically active compounds and the detection in the same 2-year-old children illustrates exposure over the first 1000 days of life.


Asunto(s)
Aflatoxina B1/análisis , Aflatoxinas/análisis , Biomarcadores/análisis , Carcinógenos/análisis , Lisina/análisis , Albúmina Sérica/análisis , Adolescente , Adulto , Aflatoxina B1/sangre , Aflatoxinas/sangre , Bangladesh , Biomarcadores/sangre , Niño , Preescolar , Estudios de Cohortes , Exposición a Riesgos Ambientales/análisis , Femenino , Humanos , Lactante , Recién Nacido , Lisina/sangre , Nepal , Embarazo , Adulto Joven
20.
J Nutr ; 144(6): 979-87, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24744314

RESUMEN

Subclinical micronutrient deficiencies remain a hidden aspect of malnutrition for which comprehensive data are lacking in school-aged children. We assessed the micronutrient status of Nepalese children, aged 6 to 8 y, born to mothers who participated in a community-based antenatal micronutrient supplementation trial from 1999 to 2001. Of 3305 participants, plasma indicators were assessed in a random sample of 1000 children. Results revealed deficiencies of vitamins A (retinol <0.70 µmol/L, 8.5%), D (25-hydroxyvitamin D <50 nmol/L, 17.2%), E (α-tocopherol <9.3 µmol/L, 17.9%), K (decarboxy prothombin >2 µg/L, 20%), B-12 (cobalamin <150 pmol/L, 18.1%), B-6 [pyridoxal-5'-phosphate (PLP) <20 nmol/L, 43.1%], and ß-carotene (41.5% <0.09 µmol/L), with little folate deficiency (6.2% <13.6 nmol/L). Deficiencies of iron [ferritin <15 µg/L, 10.7%; transferrin receptor (TfR) >8.3 mg/L, 40.1%; TfR:ferritin >500 µg/µg, 14.3%], iodine (thyroglobulin >40 µg/L, 11.4%), and selenium (plasma selenium <0.89 µmol/L, 59.0%) were observed, whereas copper deficiency was nearly absent (plasma copper <11.8 µmol/L, 0.7%). Hemoglobin was not assessed. Among all children, 91.7% experienced at least 1 micronutrient deficiency, and 64.7% experienced multiple deficiencies. Inflammation (α-1 acid glycoprotein >1 g/L, C-reactive protein >5 mg/L, or both) was present in 31.6% of children, affecting the prevalence of deficiency as assessed by retinol, ß-carotene, PLP, ferritin, TfR, selenium, copper, or having any or multiple deficiencies. For any nutrient, population deficiency prevalence estimates were altered by ≤5.4% by the presence of inflammation, suggesting that the majority of deficiencies exist regardless of inflammation. Multiple micronutrient deficiencies coexist in school-aged children in rural Nepal, meriting more comprehensive strategies for their assessment and prevention.


Asunto(s)
Anemia Ferropénica/epidemiología , Deficiencia de Ácido Fólico/epidemiología , Inflamación/epidemiología , Micronutrientes/sangre , Micronutrientes/deficiencia , Población Rural , Anemia Ferropénica/sangre , Anemia Ferropénica/tratamiento farmacológico , Proteína C-Reactiva/metabolismo , Niño , Cobre/administración & dosificación , Cobre/sangre , Cobre/deficiencia , Estudios Transversales , Suplementos Dietéticos , Femenino , Ferritinas/sangre , Deficiencia de Ácido Fólico/sangre , Deficiencia de Ácido Fólico/tratamiento farmacológico , Hemoglobinas/metabolismo , Humanos , Inflamación/sangre , Modelos Logísticos , Masculino , Micronutrientes/administración & dosificación , Nepal/epidemiología , Estado Nutricional , Prevalencia , Receptores de Transferrina/sangre , Receptores de Transferrina/deficiencia , Selenio/administración & dosificación , Selenio/sangre , Factores Socioeconómicos , Vitamina A/administración & dosificación , Vitamina A/sangre , Vitamina D/administración & dosificación , Vitamina D/análogos & derivados , Vitamina D/sangre , alfa-Tocoferol/administración & dosificación , alfa-Tocoferol/sangre
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