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1.
Matern Child Nutr ; 19(3): e13486, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36815231

RESUMO

Information on fortifiable food consumption is essential to design, monitor and evaluate fortification programmes, yet detailed methods like 24-h recalls (24HRs) that provide such data are rarely conducted. Simplified questionnaire-based methods exist but their validity compared with 24HRs has not been shown. We compared two simplified methods (i.e., a household food acquisition and purchase questionnaire [FAPQ] and a 7-day semiquantitative food frequency questionnaire [SQ-FFQ]) against 24HRs for estimating fortifiable food consumption. We assessed the consumption of fortifiable wheat flour and oil using a FAPQ and, for wheat flour only, a 7-day SQ-FFQ and compared the results against 24HRs. The participants included children 12-18 months (n = 123) and their mothers 18-49 years selected for a study assessing child vitamin A intake and status in Mandaluyong City, Philippines. For fortifiable wheat flour, the FAPQ estimated considerably lower mean intakes compared to 24HRs for children and mothers (2.2 vs. 14.1 g/day and 5.1 vs. 42.3 g/day, respectively), while the SQ-FFQ estimated slightly higher mean intakes (15.7 vs. 14.1 g/day and 51.5 vs. 42.3 g/day, respectively). For fortifiable oil, the FAPQ estimated considerably higher mean intakes compared to 24HRs for children and mothers (4.6 vs. 1.8 g/day and 12.5 vs. 6.1 g/day, respectively). The SQ-FFQ, but not the FAPQ, generated useful information on fortifiable food consumption that can inform fortification programme design and monitoring decisions in the absence of more detailed individual-level data. Potential adaptations to improve the FAPQ, such as additional questions on foods prepared away from home and usage patterns, merit further research.


Assuntos
Farinha , Alimentos Fortificados , Criança , Humanos , Filipinas , Triticum , Inquéritos e Questionários , Dieta
2.
J Nutr ; 151(12): 3874-3881, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34587254

RESUMO

BACKGROUND: Vitamin A status may influence the choice of a blood sampling time for applying the retinol isotope dilution (RID) equation to predict vitamin A total body stores (TBS) in children. OBJECTIVES: We aimed to identify time(s) after administration of labeled vitamin A that provide accurate estimates of TBS in theoretical children with low or high TBS. METHODS: We postulated 2- to 5-y-old children (12/group) with low (<200 µmol) or high TBS (≥700 µmol) and used compartmental analysis to simulate individual subject values for the RID equation TBS =   FaS/SAp (Fa, fraction of dose in stores; S, retinol specific activity in plasma/in stores; SAp, retinol specific activity in plasma). Using individual SAp and group geometric mean FaS values from 1-28 d, we calculated individual and group mean TBS and compared them to assigned values. RESULTS: Mean TBS was accurately predicted for both groups at all times. For individuals, predicted and assigned TBS were closest when the CV% for FaS was low [12-14%; 4-13 d (low), 12-28 d (high)]. The mean percentage error for TBS was <10% from 2-19 d (low) and 7-28 d (high). Predicted TBS was within 25% of assigned TBS for ≥80% of children from 3-23 d (low) and 9-28 d (high). Within groups, RID tended to overestimate lower TBS and underestimate higher TBS. CONCLUSIONS: Using a good estimate for FaS, accurate RID predictions of TBS for individuals will be obtained at many times. If vitamin A status is low, results indicate that early sampling (e.g., 4-13 d) is optimal; if vitamin A status is high, sampling at 12-28 d is indicated. When vitamin A status is unknown, sampling at 14 d is recommended, or a super-subject design can be used to obtain the group mean FaS at various times for RID prediction of TBS in individuals.


Assuntos
Deficiência de Vitamina A , Vitamina A , Criança , Humanos , Técnicas de Diluição do Indicador , Isótopos , Modelos Biológicos , Estado Nutricional , Manejo de Espécimes
3.
J Nutr ; 151(5): 1341-1346, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33755155

RESUMO

BACKGROUND: The retinol isotope dilution (RID) method has been used to evaluate vitamin A (VA) status in healthy adults and children in low- and middle-income countries (LMIC) and to assess the efficacy of various VA interventions. OBJECTIVE: The study was designed to examine whether dried serum spots (DSS) can be applied to RID when conducting VA total body store (TBS) assessments in community settings. METHODS: Four days after an oral dose of 0.4 mg [13C10]retinyl acetate was administered to Filipino children (12-18 mo), a single blood draw was divided to isolate both serum and plasma. Serum (40 µL) was spotted and dried on Whatman 903 cards and shipped at ambient temperature whereas liquid plasma (LP) was frozen at -80°C and shipped on dry ice. The VA tracer to tracee ratio from DSS and LP was quantified by LC-MS/MS. Comparisons between DSS and LP paired samples (n = 72) were made for [13C10]retinol specific activity (SAp) by Pearson's correlation and for VA TBS by Bland-Altman analysis. RESULTS: The sum of 3 coextracted DSS were required to consistently detect [13C10]retinol above the LC-MS/MS limit of quantitation (LOQ). [13C10]retinol SAp from DSS was highly correlated with SAp from LP (r = 0.945; P < 0.01). A comparison of methods for TBS determination using Bland-Altman analysis indicated agreement with an intraindividual difference of 24.7 µmol (4.6%). Mean total liver reserve (TLR) values from DSS and LP were 1.7 µmol/g (± 0.6 SD) and 1.6 µmol/g (± 0.6 SD), respectively. CONCLUSIONS: VA TBS can be determined from DSS thereby reducing the logistics and cost of maintaining a cold chain by shipping samples at ambient temperature and, thus, making the RID technique more feasible in LMIC community settings. This trial was registered at https://clinicaltrials.gov as NCT03030339.


Assuntos
Países em Desenvolvimento , Avaliação Nutricional , Estado Nutricional , Soro , Deficiência de Vitamina A/diagnóstico , Vitamina A/sangue , Cromatografia Líquida/métodos , Diterpenos/sangue , Feminino , Humanos , Técnicas de Diluição do Indicador , Lactente , Isótopos , Fígado/metabolismo , Masculino , Filipinas , Plasma/química , Refrigeração , Reprodutibilidade dos Testes , Ésteres de Retinil/sangue , Espectrometria de Massas em Tandem/métodos , Temperatura , Deficiência de Vitamina A/sangue
4.
J Nutr ; 151(4): 1029-1037, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33561214

RESUMO

BACKGROUND: Vitamin A (VA) deficiency is prevalent in preschool-aged children in sub-Saharan Africa. OBJECTIVES: We assessed the effect of small-quantity lipid-based nutrient supplements (SQ-LNS) given to women during pregnancy and lactation and their children from 6 to 18 mo of age on women's plasma and milk retinol concentrations in Malawi, and children's plasma retinol concentration in Malawi and Ghana. METHODS: Pregnant women (≤20 wk of gestation) were randomized to receive daily: 1) iron and folic acid (IFA) during pregnancy only; 2) multiple micronutrients (MMN; 800 µg retinol equivalent (RE)/capsule), or 3) SQ-LNS (800 µg RE/20g) during pregnancy and the first 6 mo postpartum. Children of mothers in the SQ-LNS group received SQ-LNS (400 µg RE/20 g) from 6 to 18 mo of age; children of mothers in the IFA and MMN groups received no supplement. Plasma retinol was measured in mothers at ≤20 and 36 wk of gestation and 6 mo postpartum, and in children at 6 and 18 mo of age. Milk retinol was measured at 6 mo postpartum. VA status indicators were compared by group. RESULTS: Among Malawian mothers, geometric mean (95% CI) plasma retinol concentrations at 36 wk of gestation and 6 mo postpartum were 0.97 µmol/L (0.94, 1.01 µmol/L) and 1.35 µmol/L (1.31, 1.39 µmol/L), respectively; geometric mean (95% CI) milk retinol concentration at 6 mo postpartum was 1.04 µmol/L (0.97, 1.13 µmol/L); results did not differ by intervention group. Geometric mean (95% CI) plasma retinol concentrations for Malawian children at 6 and 18 mo of age were 0.78 µmol/L (0.75, 0.81 µmol/L) and 0.81 µmol/L (0.78, 0.85 µmol/L), respectively, and for Ghanaian children they were 0.85 µmol/L (0.82, 0.88 µmol/L) and 0.88 µmol/L (0.85, 0.91 µmol/L), respectively; results did not differ by intervention group in either setting. CONCLUSIONS: SQ-LNS had no effect on VA status of mothers or children, possibly because of low responsiveness of the VA status indicators.


Assuntos
Suplementos Nutricionais , Lipídeos/administração & dosagem , Leite Humano/metabolismo , Vitamina A/sangue , Vitamina A/metabolismo , Adolescente , Adulto , Feminino , Gana/epidemiologia , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Lactação , Malaui/epidemiologia , Fenômenos Fisiológicos da Nutrição Materna , Mães , Estado Nutricional , Gravidez , Prevalência , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/dietoterapia , Deficiência de Vitamina A/epidemiologia , Adulto Jovem
5.
J Nutr ; 150(2): 411-418, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31535129

RESUMO

BACKGROUND: Model-based compartmental analysis has been used to describe and quantify whole-body vitamin A metabolism and estimate total body stores (TBS) in animals and humans. OBJECTIVES: We applied compartmental modeling and a super-child design to estimate retinol kinetic parameters and TBS for young children in Bangladesh, Guatemala, and the Philippines. METHODS: Children ingested [13C10]retinyl acetate and 1 or 2 blood samples were collected from each child from 6 h to 28 d after dosing. Temporal data for fraction of dose in plasma [13C10]retinol were modeled using WinSAAM software and a 6-component model with vitamin A intake included as weighted data. RESULTS: Model-predicted TBS was 198, 533, and 1062 µmol for the Bangladeshi (age, 9-17 mo), Filipino (12-18 mo), and Guatemalan children (35-65 mo). Retinol kinetics were similar for Filipino and Guatemalan groups and generally faster for Bangladeshi children, although fractional transfer of plasma retinol to a larger exchangeable storage pool was the same for the 3 groups. Recycling to plasma from that pool was ∼2.5 times faster in the Bangladeshi children compared with the other groups and the recycling number was 2-3 times greater. Differences in kinetics between groups are likely related to differences in vitamin A stores and intakes (geometric means: 352, 727, and 764 µg retinol activity equivalents/d for the Bangladeshi, Filipino, and Guatemalan children, respectively). CONCLUSIONS: By collecting 1 or 2 blood samples from each child to generate a composite plasma tracer data set with a minimum of 5 children/time, group TBS and retinol kinetics can be estimated in children by compartmental analysis; inclusion of vitamin A intake data increases confidence in model predictions. The super-child modeling approach is an effective technique for comparing vitamin A status among children from different populations. These trials were registered at www.clinicaltrials.gov as NCT03000543 (Bangladesh), NCT03345147 (Guatemala), and NCT03030339 (Philippines).


Assuntos
Modelos Biológicos , Vitamina A/farmacocinética , Bangladesh , Carga Corporal (Radioterapia) , Pré-Escolar , Países em Desenvolvimento , Guatemala , Humanos , Lactente , Filipinas
6.
Matern Child Nutr ; 14(3): e12582, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29349922

RESUMO

World Health Organization recommends exclusive breastfeeding for infants for the first 6 months of life, followed by introduction of nutritious complementary foods alongside breastfeeding. Breast milk remains a significant source of nourishment in the second half of infancy and beyond; however, it is not clear whether more breast milk is always better. The present study was designed to determine the association between amount of breast milk intake at 9-10 months of age and infant growth and development by 12-18 months of age. The study was nested in a randomized controlled trial conducted in Malawi. Regression analysis was used to determine associations between breast milk intake and growth and development. Mean (SD) breast milk intake at 9-10 months of age was 752 (244) g/day. Mean (SD) length-for-age z-score at 12 months and change in length-for-age z-score between 12 and 18 months were -1.69 (1.0) and -0.17 (0.6), respectively. At 18 months, mean (SD) expressive vocabulary score was 32 (24) words and median (interquartile range) skills successfully performed for fine, gross, and overall motor skills were 21 (19-22), 18 (16-19), and 38 (26-40), respectively. Breast milk intake (g/day) was not associated with either growth or development. Proportion of total energy intake from breast milk was negatively associated with fine motor (ß = -0.18, p = .015) but not other developmental scores in models adjusted for potential confounders. Among Malawian infants, neither breast milk intake nor percent of total energy intake from breast milk at 9-10 months was positively associated with subsequent growth between 12 and 18 months, or development at 18 months.


Assuntos
Aleitamento Materno , Desenvolvimento Infantil , Leite Humano , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Lactente , Malaui , Masculino , Destreza Motora , Estudos Prospectivos , Método Simples-Cego , Fatores Socioeconômicos
7.
J Nutr ; 147(11): 2194S-2203S, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28904117

RESUMO

Background: We previously compared the potential effects of different intervention strategies for achieving dietary vitamin A (VA) adequacy. The Lives Saved Tool (LiST) permits estimates of lives saved through VA interventions but currently only considers periodic VA supplements (VASs).Objective: We aimed to adapt the LiST method for estimating the mortality impact of VASs to estimate the impact of other VA interventions (e.g., food fortification) on child mortality and to estimate the number of lives saved by VA interventions in 3 macroregions in Cameroon.Methods: We used national dietary intake data to predict the effects of VA intervention programs on the adequacy of VA intake. LiST parameters of population affected fraction and intervention coverage were replaced with estimates of prevalence of inadequate intake and effective coverage (proportion achieving adequate VA intake). We used a model of liver VA stores to derive an estimate of the mortality reduction from achieving dietary VA adequacy; this estimate and a conservative assumption of equivalent mortality reduction for VAS and VA intake were applied to projections for Cameroon.Results: There were 2217-3048 total estimated VA-preventable deaths in year 1, with 58% occurring in the North macroregion. The relation between effective coverage and lives saved differed by year and macroregion due to differences in total deaths, diarrhea burden, and prevalence of low VA intake. Estimates of lives saved by VASs (the intervention common to both methods) were similar with the use of the adapted method (in 2012: North, 743-1021; South, 280-385; Yaoundé and Douala, 146-202) and the "usual" LiST method (North: 697; South: 381; Yaoundé and Douala: 147).Conclusions: Linking effective coverage estimates with an adapted LiST method permits estimation of the effects of combinations of VA programs (beyond VASs only) on child mortality to aid program planning and management. Rigorous program monitoring and evaluation are necessary to confirm predicted impacts.


Assuntos
Alimentos Fortificados , Micronutrientes/administração & dosagem , Deficiência de Vitamina A/dietoterapia , Deficiência de Vitamina A/mortalidade , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Camarões/epidemiologia , Criança , Mortalidade da Criança , Pré-Escolar , Dieta , Suplementos Nutricionais , Humanos , Lactente , Micronutrientes/deficiência , Modelos Teóricos , Prevalência , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
J Nutr ; 146(2): 335-42, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26740682

RESUMO

BACKGROUND: Vitamin A deficiency remains a global public health problem. Daily supplementation with a lipid-based nutrient supplement (LNS) has potential for increasing milk vitamin A concentrations. OBJECTIVE: The objective of this study was to determine whether daily supplementation with approximately the recommended daily intake of vitamin A in an LNS or a multiple-micronutrient supplement (MMN) during pregnancy and the first 6 mo postpartum has an effect on breast milk retinol concentration at 6 mo postpartum. METHODS: Women ≤20 wk pregnant (n = 1320) were randomly assigned to receive either the MMN providing 18 micronutrients, including 800 µg retinol equivalents of vitamin A, or the LNS with the same nutrients as the MMN group, plus 4 minerals and macronutrients, until 6 mo postpartum; a control group received iron and folic acid during pregnancy and a placebo (calcium tablet) during the first 6 mo postpartum. Breast milk samples collected at 6 mo postpartum were analyzed for retinol and fat concentrations by HPLC and creamatocrit, respectively, in a subsample of 756 women. RESULTS: The breast milk retinol concentration was (mean ± SD) 56.3 ± 2.1 nmol/g fat, with no significant differences between groups [iron and folic acid (n = 243): 59.1 ± 2.8; MMN (n = 260): 55.4 ± 2.5; LNS (n = 253): 54.7 ± 2.5 nmol/g fat; P = 0.45], regardless of whether the woman had or had not received a high-dose vitamin A supplement (200,000 IU) soon after childbirth. Around 17% of participants had low milk retinol (≤28 nmol/g fat). We estimated that 41% of infants were potentially receiving vitamin A at amounts above the Tolerable Upper Intake Level (600 µg retinol activity equivalents/d), with no group differences in percentages with low or high milk retinol concentration. CONCLUSION: Daily consumption of approximately the recommended intake of vitamin A did not increase breast milk retinol concentrations in this sample of Ghanaian women. This trial was registered at clinicaltrials.gov as NCT00970866.


Assuntos
Suplementos Nutricionais , Lactação/metabolismo , Lipídeos/farmacologia , Leite Humano/metabolismo , Estado Nutricional/efeitos dos fármacos , Vitamina A , Vitaminas , Adulto , Aleitamento Materno , Feminino , Gana , Humanos , Lactente , Recém-Nascido , Micronutrientes/farmacologia , Cuidado Pós-Natal , Período Pós-Parto , Gravidez , Complicações na Gravidez/tratamento farmacológico , Cuidado Pré-Natal , Recomendações Nutricionais , Vitamina A/sangue , Vitamina A/farmacologia , Deficiência de Vitamina A/tratamento farmacológico , Vitaminas/sangue , Vitaminas/farmacologia , Adulto Jovem
9.
J Nutr ; 146(9): 1783-92, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27466608

RESUMO

BACKGROUND: Provitamin A carotenoid-biofortified maize is a conventionally bred staple crop designed to help prevent vitamin A deficiency. Lactating women are a potential target group, because regularly eating biofortified maize may increase vitamin A in breast milk-a critical source of vitamin A for breastfeeding infants. OBJECTIVE: We assessed whether daily consumption of biofortified orange maize would increase the retinol concentration in the breast milk of Zambian women. METHODS: Lactating women (n = 149) were randomly assigned to receive orange maize delivering 600 µg retinol equivalents (REs)/d as carotenoid plus placebo (OM), low-carotenoid white maize plus 600 µg REs/d as retinyl palmitate (VA), or white maize plus placebo (WM). Boiled maize (287 g dry weight/d) was served as 2 meals/d, 6 d/wk for 3 wk. We measured initial and final breast milk plasma retinol and ß-carotene concentrations, and plasma inflammatory protein concentrations. RESULTS: Groups were comparable at enrollment, with an overall geometric mean milk retinol concentration of 0.95 µmol/L (95% CI: 0.86, 1.05 µmol/L); 56% of samples had milk retinol <1.05 µmol/L. Median capsule and maize intake was 97% and 258 g dry weight/d, respectively. Final milk ß-carotene did not vary across groups (P = 0.76). Geometric mean (95% CI) milk retinol concentration tended to be higher in the OM [1.15 µmol/L (0.96, 1.39 µmol/L)] and VA [1.17 µmol/L (0.99, 1.38 µmol/L)] groups than in the WM group [0.91 µmol/L (0.72, 1.14 µmol/L); P = 0.13], and the proportion of women with milk retinol <1.05 µmol/L was 52.1%, 42.9%, and 36.7% in the WM, OM, and VA groups, respectively (P-trend = 0.16). CONCLUSIONS: Daily biofortified maize consumption did not increase mean milk retinol concentration in lactating Zambian women; however, there was a plausible downward trend in the risk of low milk retinol across intervention groups. This trial was registered at clinicaltrials.gov as NCT01922713.


Assuntos
Alimentos Fortificados , Leite Humano/química , Provitaminas/administração & dosagem , Vitamina A/administração & dosagem , Vitamina A/química , Zea mays/química , Adulto , Índice de Massa Corporal , Diterpenos , Feminino , Hemoglobinas/metabolismo , Humanos , Lactação , Estado Nutricional , Provitaminas/sangue , Ésteres de Retinil , Resultado do Tratamento , Vitamina A/análogos & derivados , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/prevenção & controle , Adulto Jovem , Zâmbia
10.
J Nutr ; 146(9): 1816S-48S, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27511929

RESUMO

The Biomarkers of Nutrition for Development (BOND) project is designed to provide evidence-informed advice to anyone with an interest in the role of nutrition in health. The BOND program provides information with regard to selection, use, and interpretation of biomarkers of nutrient exposure, status, function, and effect, which will be especially useful for readers who want to assess nutrient status. To accomplish this objective, expert panels are recruited to evaluate the literature and to draft comprehensive reports on the current state of the art with regard to specific nutrient biology and available biomarkers for assessing nutritional status at the individual and population levels. Phase I of the BOND project includes the evaluation of biomarkers for 6 nutrients: iodine, folate, zinc, iron, vitamin A, and vitamin B-12. This review of vitamin A is the current article in this series. Although the vitamin was discovered >100 y ago, vitamin A status assessment is not trivial. Serum retinol concentrations are under homeostatic control due in part to vitamin A's use in the body for growth and cellular differentiation and because of its toxic properties at high concentrations. Furthermore, serum retinol concentrations are depressed during infection and inflammation because retinol-binding protein (RBP) is a negative acute-phase reactant, which makes status assessment challenging. Thus, this review describes the clinical and functional indicators related to eye health and biochemical biomarkers of vitamin A status (i.e., serum retinol, RBP, breast-milk retinol, dose-response tests, isotope dilution methodology, and serum retinyl esters). These biomarkers are then related to liver vitamin A concentrations, which are usually considered the gold standard for vitamin A status. With regard to biomarkers, future research questions and gaps in our current understanding as well as limitations of the methods are described.


Assuntos
Biomarcadores/sangue , Vitamina A/sangue , Proteínas de Fase Aguda/metabolismo , Suplementos Nutricionais , Ácido Fólico/sangue , Humanos , Iodo/sangue , Ferro/sangue , Avaliação Nutricional , Estado Nutricional , Prevalência , Saúde Pública , Ensaios Clínicos Controlados Aleatórios como Assunto , Recomendações Nutricionais , Proteínas de Ligação ao Retinol/metabolismo , Vitamina A/administração & dosagem , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/tratamento farmacológico , Deficiência de Vitamina A/epidemiologia , Vitamina B 12/sangue , Zinco/sangue
11.
Matern Child Nutr ; 12(4): 778-89, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26259833

RESUMO

Exclusive breastfeeding is recommended during the first 6 months of life; thereafter, continued breastfeeding along with nutritious complementary foods is recommended. Continued breastfeeding contributes a substantial proportion of nutrient needs and promotes healthy growth and development, but the quantity of breast milk consumed may be highly variable and little is known about the factors associated with breast milk intake after 6 months of age. The present study was conducted to assess factors associated with breast milk intake of Malawian infants at 9-10 months of age. Breast milk intake was measured using the dose-to-mother deuterium oxide dilution method in a subsample of 358 Malawian infants who were participating in a randomized controlled trial of lipid-based nutrient supplements. Regression analysis was used to assess associations between breast milk intake and several maternal and infant variables. Mean (standard deviation) breast milk intake was 752 (244) g day(-1) . In multiple regression, breast milk intake was positively associated with infant weight (+62 g per kg body weight, P < 0.01) and maternal height (P < 0.01) and negatively associated with maternal education and age (P < 0.01). There was a non-significant (P = 0.063) inverse association between energy from non-breast milk sources and breast milk intake. In this rural Malawian population, infant weight is the main predictor of breast milk intake, even after the first 6 months of life.


Assuntos
Aleitamento Materno , Dieta , Leite Humano , Adolescente , Adulto , Índice de Massa Corporal , Peso Corporal , Suplementos Nutricionais , Feminino , Humanos , Lactente , Malaui , Masculino , População Rural , Tamanho da Amostra , Fatores Socioeconômicos , Adulto Jovem
13.
J Nutr ; 144(2): 209-17, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24336458

RESUMO

Breast milk vitamin A (BMVA) has been proposed as an indicator of population vitamin A status but has rarely been applied in large-scale surveys or compared with conventional vitamin A biomarkers. We assessed the prevalence of, and risk factors for, low BMVA and its relation to vitamin A intake, plasma retinol-binding protein (pRBP), and markers of inflammation in a national survey in Cameroon. We randomly selected 30 clusters in each of 3 strata (South, North, and Cities). Casual milk samples were collected from approximately 5 women per cluster (n = 440). pRBP, plasma C-reactive protein (pCRP), plasma α1-acid glycoprotein (pAGP), and 24-h vitamin A intake were assessed in 10 women aged 15-49 y and 10 children aged 12-59 mo per cluster, including a subset of lactating women (n = 253). Low BMVA was infrequent: 7.2% (95% CI: 4.7, 9.8) of values were <1.05 µmol/L, and 9.3% (95% CI: 5.8, 12.7) were <8 µg/g fat, consistent with the low prevalence of pRBP <0.78 µmol/L among women (< 5%) but lower than the prevalence of pRBP <0.83 µmol/L among children (35%). Risk factors for both low BMVA and pRBP included living in the North and low maternal education. BMVA was positively associated with inflammation-adjusted pRBP among women in the lowest vitamin A intake tertile [<115 µg retinol activity equivalents (RAEs)/d, P < 0.01] but not in the highest tertile (>644 µg RAEs/d, P > 0.4). Controlling for milk fat, BMVA was negatively associated with pCRP (P < 0.02) but not pAGP (P > 0.5). BMVA and pRBP provide similar estimates of vitamin A deficiency prevalence and identify the same risk groups among women in Cameroon, but BMVA underestimates the prevalence of vitamin A deficiency among young children.


Assuntos
Aleitamento Materno , Lactação/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Leite Humano/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Deficiência de Vitamina A/epidemiologia , Vitamina A/metabolismo , Adolescente , Adulto , Proteína C-Reativa/metabolismo , Camarões/epidemiologia , Pré-Escolar , Escolaridade , Ingestão de Energia , Feminino , Humanos , Lactente , Inflamação/sangue , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Orosomucoide/metabolismo , Prevalência , Fatores de Risco , Vitamina A/administração & dosagem , Vitamina A/sangue , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/metabolismo , Adulto Jovem
14.
PLoS One ; 19(5): e0302968, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709803

RESUMO

INTRODUCTION: Micronutrient deficiencies are prevalent in West Africa, particularly among women of reproductive age (WRA) and young children. Bouillon is a promising food fortification vehicle due to its widespread consumption. This study aims to evaluate the impact of multiple micronutrient-fortified bouillon cubes, compared to control bouillon cubes (fortified with iodine only), on micronutrient status and hemoglobin concentrations among lactating and non-lactating WRA and young children in northern Ghana. METHODS: This randomized, controlled doubly-masked trial will be conducted in the Kumbungu and Tolon districts in the Northern Region of Ghana, where prior data indicate multiple micronutrient deficiencies are common. Participants will be: 1) non-pregnant non-lactating WRA (15-49 y), 2) children 2-5 y, and 3) non-pregnant lactating women 4-18 months postpartum. Eligible participants will be randomly assigned to receive household rations of one of two types of bouillon cubes: 1) a multiple micronutrient-fortified bouillon cube containing vitamin A, folic acid, vitamin B12, iron, zinc, and iodine, or 2) a control cube containing iodine only. Each participant's household will receive a ration of bouillon cubes every 2 weeks, and households will be advised to prepare meals as usual, using the study-provided cubes. The trial duration will be 9 months for non-pregnant non-lactating WRA and children, and 3 months for lactating women. The primary outcomes will be changes in biomarkers of micronutrient status and hemoglobin among WRA and children and milk micronutrient concentrations among lactating women. Secondary outcomes will include change in prevalence of micronutrient deficiency and anemia; dietary intake of bouillon and micronutrients; inflammation, malaria, and morbidity symptoms; and child growth and development. DISCUSSION: Evidence from this study will inform discussions about bouillon fortification in Ghana and West Africa. TRIAL REGISTRATION: The trial was registered on ClinicalTrials.gov (NCT05178407) and the Pan-African Clinical Trial Registry (PACTR202206868437931). This manuscript reflects protocol version 4 (August 29, 2022).


Assuntos
Alimentos Fortificados , Micronutrientes , Estado Nutricional , Humanos , Feminino , Gana/epidemiologia , Micronutrientes/deficiência , Micronutrientes/administração & dosagem , Micronutrientes/análise , Adulto , Adolescente , Pré-Escolar , Pessoa de Meia-Idade , Adulto Jovem , Lactação , Masculino , Hemoglobinas/análise , Iodo/deficiência , Iodo/administração & dosagem , Iodo/análise
15.
Curr Dev Nutr ; 7(3): 100053, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37181936

RESUMO

Background: Vitamin A deficiency (VAD) is common in populations with limited dietary diversity and access to vitamin A-rich foods. Objectives: This analysis aimed to determine the impact of supplementing children's diets with 1 egg/d on the concentration of plasma retinol and RBP and the prevalence of VAD. Methods: Children age 6-9 mo living in the Mangochi district of Malawi were individually randomly assigned to receive 1 egg/d for 6 mo (n = 331) or continue their usual diet (n = 329) in the Mazira trial (clinicaltrials.gov; NCT03385252). This secondary analysis measured plasma retinol by HPLC and RBP, CRP, and α-1-acid glycoprotein (AGP) by ELISA techniques at enrollment and 6 mo follow-up. Retinol and RBP were adjusted for inflammation, and mean concentrations were compared between groups using linear regression models. In addition, prevalence ratios of VAD (retinol <0.7 µmol/L) were compared between groups using log-binomial or modified Poisson regression models. Results: After 6 mo of study participation, 489 were assessed for retinol (egg: n = 238; control: n = 251), and 575 (egg: n = 281; control: n = 294) were assessed for RBP. Prevalence of inflammation (CRP >5 mg/L or AGP >1 g/L: 62%) and inflammation-adjusted VAD (7%) at enrollment did not differ between groups. At follow-up, the egg intervention group did not differ from the control in inflammation-adjusted retinol [geometric mean (95% CI); egg: 1.10 µmol/L (1.07, 1.13); control: 1.08 (1.05, 1.12)], RBP [egg: 0.99 µmol/L (0.96, 1.02); control: 0.97 (0.94, 1.00)], or prevalence of VAD [egg: 6%; control: 3%; prevalence ratio: 1.87 (0.83, 4.24)]. Conclusions: Provision of 1 egg/d did not impact VAD, plasma retinol, or RBP among young children in rural Malawi, where the prevalence of VAD was low. Curr Dev Nutr 2023;x:xx.This trial was registered at [clinicaltrials.gov] as [NCT03385252].

16.
J Nutr ; 142(10): 1896-902, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22933750

RESUMO

We assessed the effect of daily consumption of orange-fleshed sweet potatoes (OFSP), with or without added fat, on the vitamin A (VA) status of Bangladeshi women with low initial VA status. Women (n = 30/group) received one of the following for 6 d/wk over 10 wk: 1) 0 µg retinol activity equivalents (RAE)/d as boiled white-fleshed sweet potatoes (WFSP) and a corn oil capsule, 2) 600 µg RAE/d as boiled OFSP and a corn oil capsule, 3) fried OFSP and a corn oil capsule, or 4) boiled WFSP and a retinyl palmitate capsule in addition to their home diets. Plasma concentrations of retinol and ß-carotene and total body VA pool size were assessed before and after the 60-d intervention. Initial and final plasma retinol concentrations (mean ± SD) were 0.75 ± 0.18 µmol/L and 0.84 ± 0.19 µmol/L, respectively (P = 0.31); final means did not differ by group. Initial and final plasma ß-carotene concentrations were 0.10 ± 00 µmol/L and 0.18 ± 0.09 µmol/L, respectively (P < 0.0001); final mean plasma ß-carotene concentrations were higher in groups that received OFSP (P < 0.0001), and final mean plasma ß-carotene was marginally higher in the group that received fried OFSP compared with boiled OFSP (P = 0.07). Initial and final total body VA pool sizes were 0.060 ± 0.047 mmol and 0.091 ± 0.070 mmol, respectively (P = 0.05, n = 110) and did not differ by group. Despite an increase in plasma ß-carotene concentration, the impact of OFSP on VA status appears to be limited in Bangladeshi women residing in a resource-poor community.


Assuntos
Dieta , Ipomoea batatas/química , Deficiência de Vitamina A/epidemiologia , Vitamina A/sangue , beta Caroteno/sangue , Adolescente , Adulto , Antropometria , Bangladesh/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Deficiência de Vitamina A/sangue , Adulto Jovem , beta Caroteno/administração & dosagem
17.
Curr Dev Nutr ; 6(3): nzac013, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35317414

RESUMO

Background: Pregnant women in Malawi are at risk of selenium deficiency, which can have adverse effects on pregnancy outcomes. Interventions for improving selenium status are needed. Objectives: To assess the effect of provision of small-quantity lipid-based nutrient supplements (SQ-LNSs) to Malawian women during pregnancy on their plasma selenium concentrations at 36 wk of gestation. Methods: Pregnant women (≤20 wk of gestation) were randomly assigned to receive daily either: 1) iron and folic acid (IFA); 2) multiple micronutrients (MMN; 130 µg selenium per capsule); or 3) SQ-LNS (130 µg selenium/20 g). Plasma selenium concentrations were measured by inductively coupled plasma mass spectrometry at baseline and after ≥16 wk of intervention (at 36 wk of gestation) and compared by intervention group. Results: At 36 wk of gestation, median (quartile 1, quartile 3) plasma selenium concentrations (micromoles per liter) were 0.96 (0.73, 1.23), 0.94 (0.78, 1.18), and 1.01 (0.85, 1.28) in the IFA, MMN, and SQ-LNS groups, respectively. Geometric mean (GM) plasma selenium concentration was 5.4% (95% CI: 1.8%, 9.0%) higher in the SQ-LNS group than in the MMN group and tended to be higher than in the IFA group (+4.2%; 95% CI: 1.0%, 7.8%). The prevalence of adjusted plasma selenium concentrations <1 µmol/L was 55.1%, 57.8%, and 47.3% in the IFA, MMN, and SQ-LNS groups, respectively; it was lower in the SQ-LNS group than in the MMN group, OR = 0.44 (95% CI: 0.24, 0.83), and tended to be lower than in the IFA group, OR = 0.54 (95% CI: 0.29, 1.03). There was a significant interaction between baseline plasma selenium concentration and intervention group (P = 0.003). In the lowest tertile of baseline selenium concentrations, GM plasma selenium concentration was higher, and the prevalence of low values was lower in the SQ-LNS group compared with the MMN and IFA groups at 36 wk of gestation (P ≤ 0.007). Conclusions: Provision of SQ-LNS containing selenium to pregnant women can be an effective strategy for improving their selenium status.This trial was registered at clinicaltrials.gov (identifier: NCT01239693).

18.
Curr Dev Nutr ; 6(8): nzac115, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36060221

RESUMO

Background: Young children exposed to high-dose vitamin A supplements (VAS) and vitamin A (VA)-fortified foods may be at risk of high VA intake and high VA total body stores (TBS). Objectives: TBS and estimated liver VA concentration were compared among children with adequate or high VA intake and different timing of exposure to VAS, and associations between estimated liver VA concentrations and biomarkers of VA toxicity were examined. Methods: Children 12-18 mo of age (n = 123) were selected for 3 groups: 1) retinol intake >600 µg/d and VAS within the past mo, 2) retinol intake >600 µg/d and VAS in the past 3-6 mo, and 3) VA intake 200-500 µg retinol activity equivalents (RAE)/d and VAS in the past 3-6 mo. Dietary intake data were collected to measure VA intakes from complementary foods, breast milk, and low-dose, over-the-counter supplements. TBS were assessed by retinol isotope dilution, and VA toxicity biomarkers were measured. Main outcomes were compared by group. Results: Mean (95% CI) VA intakes excluding VAS were 1184 (942, 1426), 980 (772, 1187), and 627 (530, 724) µg RAE/d, in groups 1-3, respectively; mean VA intake was higher in groups 1 and 2 compared with group 3 (P < 0.05). Geometric mean (GM) (95% CI) TBS were 589 (525, 661), 493 (435, 559), and 466 (411, 528) µmol, respectively. GM TBS and GM liver VA concentrations were higher in group 1 compared with group 3 (liver VA concentration: 1.62 vs. 1.33 µmol/g; P < 0.05). Plasma retinyl ester and 4-oxo-retinoic acid concentrations and serum markers of bone turnover and liver damage did not indicate VA toxicity. Conclusions: In this sample, most children had retinol intakes above the Tolerable Upper Intake Level (UL) and liver VA concentrations above the proposed cutoff for "hypervitaminosis A" (>1 µmol/g liver). There was no evidence of chronic VA toxicity, suggesting that the liver VA cutoff value should be re-evaluated. This trial was registered at www.clinicaltrials.gov as NCT03030339.

19.
J Nutr ; 141(3): 428-32, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21248191

RESUMO

The estimated average requirement (EAR) for vitamin A (VA) of adult males is based on the amount of dietary VA required to maintain adequate function and provide a modest liver VA reserve (0.07 µmol/g). In the present study, the paired-deuterated retinol dilution technique was used to estimate changes in VA pool size in Bangladeshi men from low-income, urban neighborhoods who had small initial VA pool sizes (0.059 ± 0.032 mmol, or 0.047 ± 0.025 µmol/g liver; n = 16). The men were supplemented for 60 d with 1 of 8 different levels of dietary VA, ranging from 100 to 2300 µg/d (2 men/dietary VA level). VA pool size was estimated before and after the supplementation period. The mean change (plus or minus) in VA pool size in the men was plotted against their corresponding levels of daily VA intake and a regression line was fit to the data. The level of intake at which the regression line crossed the x-axis (where estimates of VA pool size remained unchanged) was used as an estimate of the EAR. A VA intake of 254-400 µg/d was sufficient to maintain a small VA pool size (0.059 ± 0.032 mmol) in the Bangladeshi men, corresponding to a VA intake of 362-571 µg/d for a 70-kg U.S. man, which is lower than their current EAR of 625 µg/d. The data suggest that the paired-deuterated retinol dilution technique could be used for estimating the EAR for VA for population subgroups for which there are currently no direct estimates.


Assuntos
Homeostase , Fígado/metabolismo , Necessidades Nutricionais , Vitamina A/administração & dosagem , Vitamina A/metabolismo , Adolescente , Adulto , Bangladesh , Deutério , Humanos , Técnicas de Diluição do Indicador , Masculino , Modelos Biológicos , Avaliação Nutricional , Vitamina A/sangue , Vitamina A/química , Deficiência de Vitamina A/prevenção & controle , Adulto Jovem
20.
J Nutr ; 141(12): 2233-41, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22049292

RESUMO

Variation in the relationship between plasma retinol-binding protein (RBP) and retinol (ROH) has implications for vitamin A (VA) status assessment using RBP. Our objectives were to identify factors affecting the RBP:ROH relationship and to derive and evaluate population-specific RBP cutoffs for VA deficiency (VAD) in Cameroon. Plasma RBP, C-reactive protein (CRP), α1-acid-glycoprotein (AGP), and ROH concentrations were compared in a subsample of women 15-49 y (n = 121) and children 12-59 mo (n = 123) included in a national survey conducted in 2009. Plasma RBP and ROH were highly correlated (r = 0.94 for women; r = 0.96 for children; P < 0.001). Pregnancy and lactation altered the RBP:ROH relationship in women, but obesity, elevated CRP and AGP, age, and VA status did not. Among children, age altered the RBP:ROH relationship, but sex, stunting, VA status, and elevated CRP and AGP did not. Cutoffs for VAD derived using regression analysis were <1.17 µmol RBP/L for women (corresponding to <1.05 µmol ROH/L) and <0.83 µmol RBP/L for children (corresponding to <0.70 µmol ROH/L). The sensitivity and specificity of derived cutoffs were 81.8 and 93.0% for women and 94.7 and 88.9% for children, respectively. The infection-adjusted prevalence of low VA status (<1.17 µmol RBP/L) was 21.9% (95% CI = 18.7-25.0%) among women. Among children, the infection-adjusted prevalence of VAD (<0.83 µmol RBP/L) was 35.0% (95% CI = 31.1-39.0%). In conclusion, VAD remains a public health problem in Cameroon. The RBP:ROH relationship should be considered in surveys using RBP to assess VA status, and use of population-specific cutoffs may be advisable.


Assuntos
Proteínas Plasmáticas de Ligação ao Retinol/análise , Deficiência de Vitamina A/epidemiologia , Vitamina A/sangue , Vitamina A/metabolismo , Adolescente , Adulto , Antropometria , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Camarões/epidemiologia , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Modelos Lineares , Pessoa de Meia-Idade , Estado Nutricional , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Sensibilidade e Especificidade , Fatores Socioeconômicos , Deficiência de Vitamina A/sangue , Adulto Jovem
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