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1.
J Nutr ; 154(6): 1815-1826, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599385

RESUMO

BACKGROUND: Evidence of the effectiveness of biofortified maize with higher provitamin A (PVA) to address vitamin A deficiency in rural Africa remains scant. OBJECTIVES: This study projects the impact of adopting PVA maize for a diversity of households in an area typical of rural Zimbabwe and models the cost and composition of diets adequate in vitamin A. METHODS: Household-level weighed food records were generated from 30 rural households during a week in April and November 2021. Weekly household intakes were calculated, as well as indicative costs of diets using data from market surveys. The impact of PVA maize adoption was modeled assuming all maize products contained observed vitamin A concentrations. The composition and cost of the least expensive indicative diets adequate in vitamin A were calculated using linear programming. RESULTS: Very few households would reach adequate intake of vitamin A with the consumption of PVA maize. However, from a current situation of 33%, 50%-70% of households were projected to reach ≥50% of their requirements (the target of PVA), even with the modest vitamin A concentrations achieved on-farm (mean of 28.3 µg RAE per 100 g). This proportion would increase if higher concentrations recorded on-station were achieved. The estimated daily costs of current diets (mean ± standard deviation) were USD 1.43 ± 0.59 in the wet season and USD 0.96 ± 0.40 in the dry season. By comparison, optimization models suggest that diets adequate in vitamin A could be achieved at daily costs of USD 0.97 and USD 0.79 in the wet and dry seasons, respectively. CONCLUSIONS: The adoption of PVA maize would bring a substantial improvement in vitamin A intake in rural Zimbabwe but should be combined with other interventions (e.g., diet diversification) to fully address vitamin A deficiency.


Assuntos
Biofortificação , Dieta , População Rural , Vitamina A , Zea mays , Zea mays/química , Zimbábue , Vitamina A/administração & dosagem , Humanos , Deficiência de Vitamina A/prevenção & controle , Deficiência de Vitamina A/dietoterapia , Provitaminas , Alimentos Fortificados , Estado Nutricional , Feminino , Masculino
2.
Cochrane Database Syst Rev ; 5: CD015306, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738639

RESUMO

BACKGROUND: According to global prevalence analysis studies, acute upper respiratory tract infections (URTIs) are the most common acute infectious disease in children, especially in preschool children. Acute URTIs lead to an economic burden on families and society. Vitamin A refers to the fat-soluble compound all-trans-retinol and also represents retinol and its active metabolites. Vitamin A interacts with both the innate immune system and the adaptive immune system and improves the host's defences against infections. Correlation studies show that serum retinol deficiency was associated with a higher risk of respiratory tract infections. Therefore, vitamin A supplementation may be important in preventing acute URTIs. OBJECTIVES: To assess the effectiveness and safety of vitamin A supplements for preventing acute upper respiratory tract infections in children up to seven years of age. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, the Chinese Biomedical Literature Database, and two trial registration platforms to 8 June 2023. We also checked the reference lists of all primary studies and reviewed relevant systematic reviews and trials for additional references. We imposed no language or publication restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs), which evaluated the role of vitamin A supplementation in the prevention of acute URTIs in children up to seven years of age. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. MAIN RESULTS: We included six studies (27,351 participants). Four studies were RCTs and two were cluster-RCTs. The included studies were all conducted in lower-middle-income countries (two in India, two in South Africa, one in Ecuador, and one in Haiti). Three studies included healthy children who had no vitamin A deficiency, one study included children born to HIV-infected women, one study included low-birthweight neonates, and one study included children in areas with a high local prevalence of malnutrition and xerophthalmia. In two studies, vitamin E was a co-treatment administered in addition to vitamin A. We judged the included studies to be at either a high or unclear risk of bias for random sequence generation, incomplete outcome data, and blinding. Primary outcomes Six studies reported the incidence of acute URTIs during the study period. Five studies reported the number of acute URTIs over a period of time, but there was population heterogeneity and the results were presented in different forms, therefore only three studies were meta-analysed. We are uncertain of the effect of vitamin A supplementation on the number of acute URTIs over two weeks (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.92 to 1.09; I2 = 44%; 3 studies, 22,668 participants; low-certainty evidence). Two studies reported the proportion of participants with an acute URTI. We are uncertain of the effect of vitamin A supplementation on the proportion of participants with an acute URTI (2 studies, 15,535 participants; low-certainty evidence). Only one study (116 participants) reported adverse events. No infant in either the placebo or vitamin A group was found to have feeding difficulties (failure to feed or vomiting), a bulging fontanelle, or neurological signs before or after vitamin A administration (very low-certainty evidence). Secondary outcomes Two studies (296 participants) reported the severity of subjective symptoms, presented by the mean duration of acute URTI. Vitamin A may have little to no effect on the mean duration of acute URTI (very low-certainty evidence). AUTHORS' CONCLUSIONS: The evidence for the use of vitamin A supplementation to prevent acute URTI is uncertain, because population, dose and duration of interventions, and outcomes vary between studies. From generally very low- to low-certainty evidence, we found that there may be no benefit in the use of vitamin A supplementation to prevent acute URTI in children up to seven years of age. More RCTs are needed to strengthen the current evidence. Future research should report over longer time frames using validated tools and consistent reporting, and ensure adequate power calculations, to allow for easier synthesis of data. Finally, it is important to assess vitamin A supplementation for preschool children with vitamin A deficiency.


Assuntos
Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Respiratórias , Vitamina A , Vitaminas , Humanos , Vitamina A/administração & dosagem , Infecções Respiratórias/prevenção & controle , Pré-Escolar , Lactente , Doença Aguda , Criança , Vitaminas/administração & dosagem , Deficiência de Vitamina A/prevenção & controle , Administração Oral , Viés
3.
BMC Public Health ; 24(1): 1189, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678255

RESUMO

BACKGROUND: Vitamin A deficiency (VAD) is a leading contributor to the poor health and nutrition of young children in sub-Saharan Africa. Funding constraints are compelling many countries to shift from longstanding campaigns to integrating vitamin A supplementation (VAS) into routine health services. We assessed child VAS coverage and associated factors for integrated delivery systems in Mozambique, Senegal, and Sierra Leone and for a campaign-based delivery strategy in Tanzania. METHODS: Data were obtained using representative household surveys administered to primary caregivers of N = 16,343 children aged 6-59 months (Mozambique: N = 1,659; Senegal: N = 7,254; Sierra Leone: N = 4,149; Tanzania: N = 3,281). Single-dose VAS coverage was assessed and bivariate and multivariable associations were examined for child VAS receipt with respect to rural or urban residence; child age and sex; maternal age, education, and VAS program knowledge; and household wealth. RESULTS: VAS coverage for children aged 6-59 months was 42.8% (95% CI: 40.2, 45.6) in Mozambique, 46.1% (95% CI: 44.9, 47.4) in Senegal, 86.9% (95% CI: 85.8, 87.9) in Sierra Leone, and 42.4% (95% CI: 40.2, 44.6) in Tanzania and was significantly higher for children 6-11 vs. 24-59 months in Mozambique, Senegal, and Tanzania. In Sierra Leone, children aged 12-23 months (aOR = 1.86; 95% CI: 1.20, 2.86) and 24-59 months (aOR = 1.55; 95% CI: 1.07, 2.25) were more likely to receive VAS, compared to those 6-11 months. Maternal awareness of VAS programs was associated with higher uptake in Mozambique (aOR = 4.00; 95% CI: 2.81, 5.68), Senegal (aOR = 2.72; 95% CI: 2.35, 3.15), and Tanzania (aOR = 14.50; 95% CI: 10.98, 19.17). Increased household wealth was associated with a higher likelihood of child VAS in Senegal and Tanzania. CONCLUSIONS: Our findings indicate routine delivery approaches for VAS are not achieving the level of coverage needed for public health impact in these settings. Intensive outreach efforts contributed to the higher coverage in Sierra Leone and highlight the importance of reducing the burdens associated with seeking supplementation at health facilities. As countries move towards incorporating VAS into routine health services, the essentiality of informed communities and potential losses for older children and socio-economically disadvantaged populations are key considerations in the sub-Saharan African context.


Assuntos
Suplementos Nutricionais , Deficiência de Vitamina A , Vitamina A , Humanos , Lactente , Feminino , Masculino , Pré-Escolar , Suplementos Nutricionais/estatística & dados numéricos , África Subsaariana , Deficiência de Vitamina A/prevenção & controle , Deficiência de Vitamina A/tratamento farmacológico , Deficiência de Vitamina A/epidemiologia , Vitamina A/administração & dosagem , Vitamina A/uso terapêutico , Prestação Integrada de Cuidados de Saúde , Adulto , Promoção da Saúde/métodos , Moçambique
4.
J Nutr ; 153(8): 2523-2530, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37380059

RESUMO

BACKGROUND: Although the vitamin A (VA) equivalency of provitamin A carotenoids from single foods or capsules has been studied using several approaches, there is currently no reliable method to determine VA equivalency for mixed diets. OBJECTIVES: To reach the objective of identifying a method to determine the VA equivalency of provitamin A carotenoids in mixed diets, we tested a new approach using preformed VA as proxy for provitamin A. METHODS: We studied 6 theoretical subjects who were assigned physiologically plausible values for dietary VA intake, retinol kinetic parameters, plasma retinol pool size, and VA total body stores. Using features in the Simulation, Analysis and Modeling software, we specified that subjects ingested a tracer dose of stable isotope-labeled VA on day 0 followed by 0-µg supplemental VA or 200, 400, 800, 1200, 1600, and 2000 µg VA daily from day 14 to day 28; we assigned VA absorption to be 75%. For each supplement level, we simulated plasma retinol specific activity (SAp) over time and calculated the mean decrease in SAp relative to 0 µg. Group mean data were fitted to a regression equation to calculate predicted VA equivalency at each supplement level on day 28. RESULTS: For each subject, higher VA supplement loads resulted in lower SAp, with the magnitude of the decrease differing among subjects. The mean predicted amount of absorbed VA was within 25% of individual subjects' assigned amount for 4 of the 6 subjects, and the mean ratio of predicted to assigned amount of absorbed VA over all supplement loads ranged from 0.60 to 1.50, with an overall mean ratio of 1.0. CONCLUSIONS: Results for preformed VA suggest that this protocol may be useful for determining VA equivalency of provitamin A carotenoids in free-living subjects if mixed diets with known provitamin A content were substituted for the VA supplements.


Assuntos
Deficiência de Vitamina A , Vitamina A , Humanos , Provitaminas/análise , Dieta , Deficiência de Vitamina A/prevenção & controle , Carotenoides , Suplementos Nutricionais/análise
5.
BMC Pediatr ; 23(1): 257, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221505

RESUMO

BACKGROUND: Vitamin A deficiency is one of the major public health problems in low and middle-income countries including Ethiopia. Despite this fact, little attention was given to routine vitamin A supplementation in hard-to-reach rural areas and districts. Therefore, this study aimed to assess vitamin A supplementation coverage and its associated factors among children aged 6-59 months in West Azernet Berbere woreda, southern Ethiopia, 2021. METHODS: A community-based cross-sectional study was conducted from April to May 2021. A total sample size of 471 study participants was involved in the study area. A simple random sampling technique was used to recruit the study subject. A pretested structured interviewer-administered questionnaire was used. Bivariable and multivariable logistic regression analyses were done to identify variables having a significant association with vitamin A supplementation. The variables having a p-value ≤ 0.05 with 95% CI were used to declare an association between factors and a dependent variable. RESULTS: In this study, a total of 471 respondents were successfully interviewed with a response rate of 97.3%. The coverage of vitamin A supplementation was found to be 58.0%. Family monthly income [AOR = 2.565, 95% CI(1.631,4.032)], having PNC visit [AOR = 1.801, 95% CI (1.158, 2.801)], husbands disapproval about vitamin A supplementation [AOR = 0.324, 95% CI (0.129, 0.813)], information about vitamin A supplementation [AOR = 2.932, 95% CI (1.893, 4,542)] and ANC follow-up [AOR = 1.882, 95% CI (1.084, 3.266)] were factors significantly associated to vitamin A supplementation. CONCLUSION: Vitamin A supplementation was found to be low and it is strongly associated with family monthly income, postnatal care, husband's disapproval of vitamin A supplementation, antenatal care follow-up, and information about vitamin A supplementation. Based on our findings, it is recommended to improve the monthly income of the household by actively engaging in various income-generating activities, enhance health information dissemination among mothers, particularly those who are underprivileged by using different strategies like local health campaigns, and mass media, advocacy of antenatal, and postnatal follow-up and promote the involvement of males/husband in childhood immunization service.


Assuntos
Deficiência de Vitamina A , Vitamina A , Criança , Feminino , Humanos , Masculino , Gravidez , Estudos Transversais , Suplementos Nutricionais , Etiópia/epidemiologia , Vitamina A/administração & dosagem , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
6.
Matern Child Health J ; 27(7): 1284-1292, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37166572

RESUMO

OBJECTIVES: In Africa and Asia, 190 million preschoolers are vitamin A deficient. This study examined the social determinants of intake of vitamin A supplementation (VAS) among children aged 6-59 months during three different time periods in Kenya to identify those most vulnerable to vitamin A deficiency and highlight the varied targeting and outreach efforts; before the onset of a national restructuring and targeted distribution of VAS in children below 5 years through a twice-yearly door-to-door campaign called Child Health Weeks, during the implementation period, and several years later. METHODS: The cross-sectional, national Demographic and Health Surveys were administered in Kenya in 2003, 2008-09, and 2014. Bivariate and multivariable logistic regression analyses were used to assess variables associated with VAS among children (n = 28,239). RESULTS: An overall two-fold increase in VAS was recorded between 2003 (31.8%) and 2014 (67.5%). In 2008-09, children aged 6-11 months were the most likely to receive VAS. In 2003 and 2014, geographical regions and settings, birth order of the child, educational level of the mother, religion, wealth index, number of antenatal visits, and access to a radio were identified as being significantly associated with VAS, in at least one of the years. These determinants were not significant in 2008-09 during the initial Child Health Weeks promotion campaign. The determinants of VAS varied during the three study periods, particularly in 2008-09 when the Child Health Weeks was first implemented. CONCLUSION: As efforts to increase VAS continue, addressing child-specific determinants will be essential to reduce health disparities.


Assuntos
Deficiência de Vitamina A , Vitamina A , Gravidez , Humanos , Feminino , Lactente , Quênia/epidemiologia , Estudos Transversais , Determinantes Sociais da Saúde , Suplementos Nutricionais , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
7.
Crit Rev Food Sci Nutr ; 62(22): 6103-6112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33683154

RESUMO

The risk of child vitamin A deficiency (VAD) in low and middle income countries (LMICs) begins during the age range of complementary feeding (6-24 months), when children are fed complementary foods (CFs) deficient in vitamin A. However, pumpkin, a source of provitamin A carotenoids (PVACs) is widely cultivated in LMICs, but underutilized as a complementary food. Moreover, when consumed by humans, PVACs are bioconverted to retinol, the active form of vitamin A used by the body. This study evaluated the potential of pumpkin toward combating VAD by reviewing varieties of pumpkin cultivated in LMICs and their provitamin A carotenoid (PVAC) content; retention of PVACs in pumpkin during processing it as a CF; and the extent to which a CF prepared from pumpkin may meet the dietary reference intakes (DRIs) for vitamin A for children aged 6-24 months old. Pumpkin may combat VAD because the varieties cultivated have high ß-carotene content, it is a provitamin A biofortifiable food crop, and 100% retention of PVACs was observed when processed using home cooking methods. Feeding less than 50 g of cooked pumpkin per day meets 100% of the recommended dietary allowance (RDA) and adequate intake (AI) of vitamin A for children 6 to 24 months old. Consumption of pumpkin may be used to complement vitamin A supplementation, fortification, and diversification of CFs with animal source foods. For better yield of pumpkin in LMICs, nutrition sensitive agricultural programmes such as biofortification and agronomic management of pumpkin need to be promoted and supported.


Assuntos
Cucurbita , Deficiência de Vitamina A , Animais , Carotenoides , Criança , Pré-Escolar , Países em Desenvolvimento , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Provitaminas , Recomendações Nutricionais , Vitamina A , Deficiência de Vitamina A/prevenção & controle
8.
Cochrane Database Syst Rev ; 3: CD008524, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35294044

RESUMO

BACKGROUND: Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to many adverse health consequences, including death. Based on prior evidence and a previous version of this review, the World Health Organization has continued to recommend vitamin A supplementation (VAS) for children aged 6 to 59 months. The last version of this review was published in 2017, and this is an updated version of that review. OBJECTIVES: To assess the effects of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged six months to five years. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, six other databases, and two trials registers up to March 2021. We also checked reference lists and contacted relevant organisations and researchers to identify additional studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) and cluster-RCTs evaluating the effect of synthetic VAS in children aged six months to five years living in the community. We excluded studies involving children in hospital and children with disease or infection. We also excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods, or beta-carotene supplementation. DATA COLLECTION AND ANALYSIS: For this update, two review authors independently assessed studies for inclusion resolving discrepancies by discussion. We performed meta-analyses for outcomes, including all-cause and cause-specific mortality, disease, vision, and side effects. We used the GRADE approach to assess the quality of the evidence. MAIN RESULTS: The updated search identified no new RCTs. We identified 47 studies, involving approximately 1,223,856 children. Studies were set in 19 countries: 30 (63%) in Asia, 16 of these in India; 8 (17%) in Africa; 7 (15%) in Latin America, and 2 (4%) in Australia. About one-third of the studies were in urban/periurban settings, and half were in rural settings; the remaining studies did not clearly report settings. Most studies included equal numbers of girls and boys and lasted about one year. The mean age of the children was about 33 months. The included studies were at variable overall risk of bias; however, evidence for the primary outcome was at low risk of bias. A meta-analysis for all-cause mortality included 19 trials (1,202,382 children). At longest follow-up, there was a 12% observed reduction in the risk of all-cause mortality for VAS compared with control using a fixed-effect model (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83 to 0.93; high-certainty evidence). Nine trials reported mortality due to diarrhoea and showed a 12% overall reduction for VAS (RR 0.88, 95% CI 0.79 to 0.98; 1,098,538 children; high-certainty evidence). There was no evidence of a difference for VAS on mortality due to measles (RR 0.88, 95% CI 0.69 to 1.11; 6 studies, 1,088,261 children; low-certainty evidence), respiratory disease (RR 0.98, 95% CI 0.86 to 1.12; 9 studies, 1,098,538 children; low-certainty evidence), and meningitis. VAS reduced the incidence of diarrhoea (RR 0.85, 95% CI 0.82 to 0.87; 15 studies, 77,946 children; low-certainty evidence), measles (RR 0.50, 95% CI 0.37 to 0.67; 6 studies, 19,566 children; moderate-certainty evidence), Bitot's spots (RR 0.42, 95% CI 0.33 to 0.53; 5 studies, 1,063,278 children; moderate-certainty evidence), night blindness (RR 0.32, 95% CI 0.21 to 0.50; 2 studies, 22,972 children; moderate-certainty evidence), and VAD (RR 0.71, 95% CI 0.65 to 0.78; 4 studies, 2262 children, moderate-certainty evidence). However, there was no evidence of a difference on incidence of respiratory disease (RR 0.99, 95% CI 0.92 to 1.06; 11 studies, 27,540 children; low-certainty evidence) or hospitalisations due to diarrhoea or pneumonia. There was an increased risk of vomiting within the first 48 hours of VAS (RR 1.97, 95% CI 1.44 to 2.69; 4 studies, 10,541 children; moderate-certainty evidence). AUTHORS' CONCLUSIONS: This update identified no new eligible studies and the conclusions remain the same. VAS is associated with a clinically meaningful reduction in morbidity and mortality in children. Further placebo-controlled trials of VAS in children between six months and five years of age would not change the conclusions of this review, although studies that compare different doses and delivery mechanisms are needed. In populations with documented VAD, it would be unethical to conduct placebo-controlled trials.


Assuntos
Sarampo , Transtornos Respiratórios , Deficiência de Vitamina A , Criança , Pré-Escolar , Diarreia/induzido quimicamente , Suplementos Nutricionais , Feminino , Humanos , Masculino , Sarampo/induzido quimicamente , Sarampo/complicações , Morbidade , Vitamina A/uso terapêutico , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
9.
Compr Rev Food Sci Food Saf ; 21(3): 2772-2819, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35384290

RESUMO

Vitamin A is an essential micronutrient whose deficiency is still a major health concern in many regions of the world. It plays an essential role in human growth and development, immunity, and vision, but may also help prevent several other chronic diseases. The total amount of vitamin A in the human diet often falls below the recommended dietary allowance of approximately 900-1000 µ$ \umu $ g/day for a healthy adult. Moreover, a significant proportion of vitamin A may be degraded during food processing, storage, and distribution, thereby reducing its bioactivity. Finally, the vitamin A in some foods has a relatively low bioavailability, which further reduces its efficacy. The World Health Organization has recommended fortification of foods and beverages as a safe and cost-effective means of addressing vitamin A deficiency. However, there are several factors that must be overcome before effective fortified foods can be developed, including the low solubility, chemical stability, and bioavailability of this oil-soluble vitamin. Consequently, strategies are required to evenly disperse the vitamin throughout food matrices, to inhibit its chemical degradation, to avoid any adverse interactions with any other food components, to ensure the food is palatable, and to increase its bioavailability. In this review article, we discuss the chemical, physical, and nutritional attributes of vitamin A, its main dietary sources, the factors contributing to its current deficiency, and various strategies to address these deficiencies, including diet diversification, biofortification, and food fortification.


Assuntos
Deficiência de Vitamina A , Vitamina A , Adulto , Alimentos Fortificados , Humanos , Micronutrientes , Deficiência de Vitamina A/prevenção & controle , Vitaminas
10.
Matern Child Nutr ; 18 Suppl 1: e12954, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32108438

RESUMO

Nepal has a rich history of vitamin A research and a national, biannual preschool vitamin A supplementation (VAS) programme that has sustained high coverage for 25 years despite many challenges, including conflict. Key elements of programme success have included (a) evidence of a 26-30% reduction in child mortality from two, in-country randomized trials; (b) strong political and donor support; (c) positioning local female community health volunteers as key operatives; (d) nationwide community mobilization and demand creation for the programme; and (e) gradual expansion of the programme over a period of several years, conducting and integrating delivery research, and monitoring to allow new approaches to be tested and adapted to available resources. The VAS network has served as a platform for delivering other services, including anthelmintic treatment and screening for acute malnutrition. We estimate that VAS has saved over 45,000 young lives over the past 15 years of attained national coverage. Consumption of vitamin A- and carotenoid-rich foods by children and women nationally remains low, indicating that supplementation is still needed. Current challenges and opportunities to improving vitamin A status include lower VAS coverage among younger children (infants 6-11 months of age), finding ways to increase availability and access to dietary vitamin A sources, and ensuring local programme investments given the recent decentralization of the government.


Assuntos
Deficiência de Vitamina A , Vitamina A , Criança , Mortalidade da Criança , Pré-Escolar , Dieta , Feminino , Humanos , Lactente , Nepal/epidemiologia , Vitamina A/uso terapêutico , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
11.
Annu Rev Nutr ; 40: 1-23, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966182

RESUMO

My career as an accidental nutritionist began with my immersion in cholera control, a cyclone disaster, a smallpox epidemic, and formal training in ophthalmology and epidemiology. Interest in blindness prevention inexplicably led me to (re)pioneer the effects, treatment, and prevention of vitamin A deficiency, while faced with intense criticism by many leading scientists in the nutrition community. The resulting efforts by the World Health Organization and UNICEF in support of programs for the global control of vitamin A deficiency still face vocal opposition by some senior scientists, despite having been estimated to have saved tens of millions of children from unnecessary death and blindness. This entire journey was largely an accident!


Assuntos
Pesquisa Biomédica/história , Ciências da Nutrição/história , Nutricionistas/história , Criança , Fenômenos Fisiológicos da Nutrição Infantil , História do Século XX , Humanos , Indonésia , Deficiência de Vitamina A/história , Deficiência de Vitamina A/prevenção & controle , Xeroftalmia/etiologia , Xeroftalmia/história , Xeroftalmia/patologia
12.
BMC Public Health ; 21(1): 648, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33794858

RESUMO

BACKGROUND: Vitamin A deficiency (VAD) is a prominent and widespread public health problem in developing countries, including Bangladesh. About 2% of all deaths among under-five children are attributable to VAD. Evidence-based information is required to understand the influential factors to increase vitamin A supplementation (VAS) coverage and reduce VAD. We investigated the potential factors affecting VAS coverage and its significant predictors among Bangladeshi children aged 6 to 59 months using the VAS clustered data extracted from the latest Bangladesh Demographic and Health Survey 2014. METHODS: Data were analysed using mixed logistic regression (MLR) modelling approach in the generalised linear mixed model framework. The MLR model performs better than logistic regression for analysing the clustered data because of its minimum Akaike information criterion value. The likelihood ratio test showed that the variance component was significant. Therefore, the clustering effect among children was inevitable to use. RESULTS: VAS coverage among under-five children was 63.6%, which is not optimal and below the WHO's recommendation and the country's target of 90%. Children aged 25 to 36 months (AOR = 2.07, 95% CI: 1.711 to 2.513), who had higher educated mothers (AOR = 1.37, p = 0.033, 95% CI: 1.026-1.820) and fathers (AOR = 1.32, p = 0.027, 95% CI: 1.032-1.683), whose mothers had media exposure (AOR = 1.22, p = 0.006, 95% CI: 1.059-1.408) and NGO membership (AOR = 1.24, p = 0.002, 95% CI: 1.089-1.422) were more likely to consume VAS. CONCLUSION: The relevant authorities should create proactive awareness programs for highly vulnerable local communities, specifically targeted to educate the children's mothers about the necessity and benefits of childhood nutrition.


Assuntos
Deficiência de Vitamina A , Vitamina A , Bangladesh/epidemiologia , Criança , Pré-Escolar , Suplementos Nutricionais , Feminino , Humanos , Lactente , Fatores Socioeconômicos , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
13.
Matern Child Nutr ; 17(3): e13132, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33336556

RESUMO

Vitamin A supplementation (VAS), started as a short-term strategy pending dietary improvements, has been implemented in Ethiopia for the last 15 years. We aimed to describe the trends in VAS coverage and estimated the associated reductions in child mortality. VAS coverage data obtained from the District Health Information System and the Demographic and Health Surveys were linked to child mortality data from the United Nations Interagency Group for Child Mortality Estimation (UN IGME). The number of child deaths averted was modelled assuming 12% and 24% reductions in all-cause mortality. From 2006 to 2011, VAS was delivered through campaigns, and coverage was above 85%. However, from 2011 onwards, VAS delivery was integrated to the routine health system, and the coverage declined to <60% with significant disparities by wealth quintile and rural-urban residence. VAS has saved between 167,563 to 376,030 child lives (2005-2019), but additional lives (>42,000) could have been saved with a universal coverage (95%). Inconsistent supply of vitamin A capsules, but more importantly, low access to health care, and the limited contact opportunities for children after 24 months may have contributed to the declining VAS coverage. Any changes in target or scale-up should thus consider these spatial and socioeconomic variations. Increasing the coverage of VAS and closing the equity gap in access to nutrition services is critical. However, with alternative programmes like vitamin A fortification being set-up, the benefits and safety of VAS need to be closely monitored, particularly in areas where there will be overlap.


Assuntos
Deficiência de Vitamina A , Vitamina A , Criança , Mortalidade da Criança , Suplementos Nutricionais , Etiópia/epidemiologia , Humanos , Lactente , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
14.
J Nutr ; 150(4): 938-944, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923315

RESUMO

BACKGROUND: Micronutrient powders (MNP) can reduce iron deficiency and anemia in children. OBJECTIVE: We evaluated the impact of an integrated infant and young child feeding (IYCF)-MNP intervention on anemia and micronutrient status among children aged 12-23 mo in Eastern Uganda. The intervention focused on MNP distribution, IYCF education, and caregiver behavior change. METHODS: Population-based cross-sectional surveys representative of children aged 12-23 mo in Amuria (intervention) and Soroti (nonintervention) districts were collected in June/July 2015 at baseline (n = 1260) and 12 mo after implementation at endline in 2016 (n = 1490). From pooled capillary blood, we assessed hemoglobin, malaria, ferritin, retinol binding protein (RBP), C-reactive protein, and ɑ1-acid glycoprotein. Ferritin and RBP were regression-adjusted to correct for inflammation. Caregivers reported sociodemographic characteristics and MNP knowledge and practices. Linear regression estimated the difference-in-difference (DiD) effect of MNP on hemoglobin, ferritin, and RBP, and logistic regression estimated DiD effect of MNP on anemia (hemoglobin <11.0 g/dL), iron deficiency (ferritin <12.0 µg/L), iron deficiency anemia (hemoglobin <11.0 g/dL and ferritin <12.0 µg/L), and vitamin A deficiency (VAD; RBP equivalent to <0.70 µmol/L retinol: <0.79 µmol/L at baseline and RBP <0.67 µmol/L at endline). RESULTS: In Amuria, 96% of children had ever consumed MNP versus <1% of children in Soroti. Fifty-four percent of caregivers reported organoleptic changes when MNP were added to foods cooked with soda ash. Adjusting for age, sex, malaria, recent morbidity, and household-level factors, the intervention was associated with -0.83 g/dL lower hemoglobin (95% CI, -1.36, -0.30 g/dL; P = 0.003) but not with anemia, ferritin, iron deficiency, iron deficiency anemia, RBP, or VAD. CONCLUSIONS: Despite high program fidelity, the intervention was associated with reduced hemoglobin concentrations but not with change in anemia or micronutrient status among children aged 12-23 mo in Eastern Uganda. Contextual factors, such as cooking with soda ash, might explain the lack of effectiveness.


Assuntos
Anemia/prevenção & controle , Suplementos Nutricionais , Ferro/administração & dosagem , Micronutrientes/administração & dosagem , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Anemia/epidemiologia , Anemia Ferropriva/sangue , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Estado Nutricional , Projetos Piloto , Pós , Uganda/epidemiologia , Deficiência de Vitamina A/epidemiologia
15.
J Nutr ; 150(11): 3005-3012, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32939553

RESUMO

BACKGROUND: Vitamin A (VA) stores are low in early infancy and may impair development of the immune system. OBJECTIVE: This study determined if neonatal VA supplementation (VAS) affects the following: 1) development of regulatory T (Treg) cells; 2) chemokine receptor 9 (CCR9) expression, which directs mucosal targeting of immune cells; and 3) systemic endotoxin exposure as indicated by changed plasma concentrations of soluble CD14 (sCD14). Secondarily, VA status, growth, and systemic inflammation were investigated. METHODS: In total, 306 Bangladeshi infants were randomly assigned to receive 50,000 IU VA or placebo (PL) within 48 h of birth, and immune function was assessed at 6 wk, 15 wk, and 2 y. Primary outcomes included the following: 1) peripheral blood Treg cells; 2) percentage of Treg, T, and B cells expressing CCR9; and 3) plasma sCD14. Secondary outcomes included the following: 4) VA status measured using the modified relative dose-response (MRDR) test and plasma retinol; 5) infant growth; and 6) plasma C-reactive protein (CRP). Statistical analysis identified group differences and interactions with sex and birthweight. RESULTS: VAS increased (P = 0.004) the percentage of CCR9+ Treg cells (13.2 ± 1.37%) relative to PL (9.17 ± 1.15%) in children below the median birthweight but had the opposite effect (P = 0.04) in those with higher birthweight (VA, 9.13 ± 0.89; PL, 12.1 ± 1.31%) at 6 and 15 wk (values are combined mean ± SE). VAS decreased (P = 0.003) plasma sCD14 (1.56 ± 0.025 mg/L) relative to PL (1.67 ± 0.032 mg/L) and decreased (P = 0.034) the prevalence of VA deficiency (2.3%) relative to PL (9.2%) at 2 y. CONCLUSIONS: Neonatal VAS enhanced mucosal targeting of Treg cells in low-birthweight infants. The decreased systemic exposure to endotoxin and improved VA status at 2 y may have been due to VA-mediated improvements in gut development resulting in improved barrier function and nutrient absorption. This trial was registered at clinicaltrials.gov as NCT01583972 and NCT02027610.


Assuntos
Receptores CCR/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Bangladesh/epidemiologia , Peso ao Nascer , Pré-Escolar , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Humanos , Recém-Nascido , Receptores de Lipopolissacarídeos/genética , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Receptores CCR/genética , Linfócitos T Reguladores/metabolismo , Deficiência de Vitamina A/epidemiologia
16.
J Hum Nutr Diet ; 33(5): 678-685, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32424967

RESUMO

BACKGROUND: Vitamin A plays an important role in vision, cellular differentiation, embryonic development, reproduction, growth and the immune system. Women who live in developing countries face a risk of undernutrition during pregnancy as a result of poverty, poor diet quality and quantity, and a high fertility rate. This poor dietary problem could reflect the high risk of vitamin A deficiency in women. The present study aimed to determine the adequacy of vitamin A among pregnant women following antenatal care in health facilities of Dessie Town, Ethiopia, January 2017. METHODS: Health facility-based cross-sectional study was conducted among 390 women who attended antenatal care in Dessie Town. Food groups from the Food and Agriculture Organization based on 24-h dietary recall were used to measure dietary intake of vitamin A and dietary diversity of women. Adequacy of vitamin A was determined from the nutrient adequacy ratio after obtaining reports of nutrient intake from food composition tables version III and IV in terms of B carotene and retinol equivalent, respectively, based on the estimated average requirement recommendation of vitamin A, 370 retinol equivalent day-1 for pregnant women. Multivariable logistic regression analysis was performed to identify associated factors of vitamin A adequacy. RESULTS: Adequacy of vitamin A among pregnant women was 41.8%, with an average nutrient adequacy ratio of 0.9. The mean dietary intake of vitamin A was 290.1 µg day-1 . The predictors for adequacy of vitamin A were high and medium women diversity scores (adjusted odds ratio = 2.92; 95% confidence interval = 1.50-5.70) and (adjusted odds ratio = 1.87; 95% confidence interval = 1.11-3.16). CONCLUSIONS: In the present study, adequacy of vitamin A was low and was affected by the dietary diversity score. A focus on food-based approaches, especially regarding educating pregnant women to diversify their diet, is crucial for reducing the risk of vitamin A deficiency. Vitamin A is crucial micronutrient for the health of women and fetus, being essential for morphological, ocular and functional developments, as well as fetal organ and skeletal growth. Its requirement is greater during pregnancy and its deficiencies lead to maternal and child mortality and development. The dietary intake of vitamin A among pregnant women remains below the current recommendation. Inadequate intake of vitamin A Pregnant women Heath facility Dessie, Ethiopia.


Assuntos
Dieta Saudável/estatística & dados numéricos , Cuidado Pré-Natal/estatística & dados numéricos , Vitamina A/análise , Adulto , Estudos Transversais , Inquéritos sobre Dietas , Etiópia , Feminino , Instalações de Saúde/estatística & dados numéricos , Humanos , Razão de Chances , Gravidez , Complicações na Gravidez/prevenção & controle , Deficiência de Vitamina A/prevenção & controle
17.
Matern Child Nutr ; 16(3): e12931, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31845541

RESUMO

Previous research has demonstrated a virtual absence of vitamin A deficiency and adequacy of vitamin A intake through consumption of liver in preschool children of a community in the Northern Cape province of South Africa where sheep farming is common, and liver, an exceptionally rich source of vitamin A, is frequently eaten. Only 60-75 g of liver per month is needed to meet the vitamin A requirement of preschool children. Because this may have implications for routine vitamin A supplementation, and because liver consumption for the rest of the province is unknown, the study aim was to establish the prevalence and frequency of liver intake in a provincial-wide survey. An unquantified liver-specific food frequency questionnaire, covering a period of 1 month, complemented by a 1-year recall, was administered to mothers of 2- to 5-year-old children (n = 2,864) attending primary health care facilities in all five districts and 26 subdistricts. A total of 86% of children were reported to eat liver, which was eaten in all districts by at least 80% of children. The overall median frequency of liver intake was 1.0 [25th, 75th percentiles: 0.5, 3.0] times per month and ranged from 1.0 [0.3, 2.0] to 2.0 [1.0, 4.0] for the various districts. Based on a previously reported portion size of 66 g, these results suggest vitamin A dietary adequacy in all districts and possibly also vitamin A intake exceeding the Tolerable Upper Intake Level in some children. Routine vitamin A supplementation in this province may not be necessary and should be reconsidered.


Assuntos
Dieta/métodos , Carne , Inquéritos Nutricionais/estatística & dados numéricos , Estado Nutricional , Deficiência de Vitamina A/prevenção & controle , Vitamina A/sangue , Animais , Pré-Escolar , Feminino , Humanos , Fígado , Masculino , Inquéritos Nutricionais/métodos , Ovinos , África do Sul
18.
Ecol Food Nutr ; 59(6): 615-638, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32406767

RESUMO

The study assesses the psychosocial predictors of intention to integrate biofortified pro-vitamin A orange-fleshed sweet potato (OFSP) in proper complementary feeding (PCF) among women who received either verbal or verbal and visual demonstrations on OFSP-based foods. A total of 764 randomly selected women grouped into four categories, namely pregnant women, women with infants, women with young children, and potential mothers, participated in this study. Using a structural equation model of predicted intentions based on an extended Theory of Planned Behavior (TPB) the study found goal-setting, perceived behavior control, subjective norms, and attitudes had a significant influence on intention to integrate OFSP in PCF. Unexpectedly, knowledge of the various health benefits of OFSP did not positively influence intention. Probabilistic recursive regression was then used to estimate the relationship between the intention to provide PCF practices and its potential antecedents. The results then showed that the model structure and explanatory power was information-specific and also revealing outcome differences by category of women. These results have implications on how interventions targeting the improvement of PCF should be organized and delivered. They underscore the need to segment the audience during nutrition education.


Assuntos
Comportamento Alimentar , Alimentos Fortificados , Educação em Saúde/métodos , Fenômenos Fisiológicos da Nutrição do Lactente , Intenção , Ipomoea batatas , População Rural , Adolescente , Adulto , Saúde da Criança , Pré-Escolar , Cor , Feminino , Promoção da Saúde/métodos , Humanos , Lactente , Recém-Nascido , Quênia , Pessoa de Meia-Idade , Mães , Gravidez , Vitamina A , Deficiência de Vitamina A/prevenção & controle , Adulto Jovem
19.
Crit Rev Food Sci Nutr ; 59(21): 3498-3510, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29999424

RESUMO

Vitamin A deficiency (VAD) is one of the most prevalent micronutrient deficiencies that disproportionately affects low income populations in developing countries. Traditional breeding and modern biotechnology have significant potential to enhance micronutrient bioavailability in crops through biofortification. Bananas (Musa spp.) are economically important fruit crops grown throughout tropical and sub-tropical regions of the world where VAD is most prevalent. Some banana genotypes are rich in provitamin A carotenoids (pVACs), providing an opportunity to use bananas as a readily available vehicle for provitamin A delivery. This review summarizes the progress made in carotenoid research in bananas relative to banana diversity and the use of conventional breeding and transgenic approaches aimed at banana biofortification to address vitamin A deficiency. Existing reports on sampling strategies, pVAC retention and bioavailability are also evaluated as essential components for a successful banana biofortification effort. The wide variability of pVACs reported in banana cultivars coupled with recent advances in unraveling the diversity and genetic improvement of this globally important but often-neglected staple fruit crop underscores their importance in biofortification schemes.


Assuntos
Biofortificação , Musa , Deficiência de Vitamina A/prevenção & controle , Vitamina A , Humanos , Provitaminas
20.
Crit Rev Food Sci Nutr ; 59(8): 1284-1293, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29200311

RESUMO

Micronutrient deficiencies have been identified as major public health problems affecting a large part of the world's population. Biofortification of staple crops like maize has been proposed as one of the most cost effective and feasible approaches to combat micronutrient deficiencies. Studies have shown that provitamin A from biofortified crops is highly bioavailable and has the capacity to improve vitamin A status of vulnerable groups. Most people in sub-Saharan Africa subsist on maize and many people may benefit from consumption of provitamin A carotenoid biofortified maize, especially women and children. With the exception of transgenic golden rice, biofortified crops have received considerable acceptance by most communities. Negative perceptions associated with yellow maize do not affect orange maize, which is, for example, well-liked in rural Zambia. With proper policy frameworks and full commercialization, provitamin A maize can address the problem of vitamin A deficiencies among poor nations with maize-based diets.


Assuntos
Biofortificação , Carotenoides/metabolismo , Países em Desenvolvimento , Alimentos Fortificados , Provitaminas/metabolismo , Vitamina A/metabolismo , Zea mays/química , Criança , Feminino , Humanos , Oryza , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Deficiência de Vitamina A/prevenção & controle , Zea mays/genética
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