RESUMO
Biofortification is a promising strategy to combat micronutrient malnutrition by promoting the adoption of staple food crops bred to be dense sources of specific micronutrients. Research on biofortified orange-fleshed sweet potato (OFSP) has shown that the crop improves the vitamin A status of children who consume as little as 100 grams per day, and intensive promotion strategies improve dietary intakes of vitamin A in field experiments. However, little is known about OFSP adoption behavior, or about the role that nutrition information plays in promoting adoption and changing diet. We report evidence from similar randomized field experiments conducted in Mozambique and Uganda to promote OFSP. We further use causal mediation analysis to study impact pathways for adoption and dietary intakes. Despite different agronomic conditions and sweet potato cropping patterns across the two countries, the project had similar impacts, leading to adoption by 61% to 68% of farmers exposed to the project, and doubling vitamin A intakes in children. In both countries, two intervention models that differed in training intensity and cost had comparable impacts relative to the control group. The project increased the knowledge of key nutrition messages; however, added knowledge of nutrition messages appears to have minimally affected adoption, conditional on assumptions required for causal mediation analysis. Increased vitamin A intakes were largely explained by adoption and not by nutrition knowledge gained, though in Uganda a large share of impacts on vitamin A intakes cannot be explained by mediating variables. Similar impacts could likely have been achieved by reducing the scope of nutrition trainings. JEL codes: I15, O12, O13, Q12.
RESUMO
OBJECTIVE: To formulate age- and context-specific complementary feeding recommendations (CFR) for infants and young children (IYC) and to compare the potential of filling population-level nutrient gaps using common sets of CFR across age groups. DESIGN: Linear programming was used to develop CFR using locally available and acceptable foods based on livelihood- and age-group-specific dietary patterns observed through 24 h dietary recalls. Within each livelihood group, the nutrient potential of age-group-specific v. consolidated CFR across the three age groups was tested. SETTING: Three food-insecure counties in northern Kenya; namely, settled communities from Isiolo (n 300), pastoralist communities from Marsabit (n 283) and agro-pastoralist communities from Turkana (n 299). SUBJECTS: Breast-fed IYC aged 6-23 months (n 882). RESULTS: Age-specific CFR could achieve adequacy for seven to nine of eleven modelled micronutrients, except among 12-23-month-old children in agro-pastoralist communities. Contribution of Fe, Zn and niacin remained low for most groups, and thiamin, vitamin B6 and folate for some groups. Age-group-consolidated CFR could not reach the same level of nutrient adequacy as age-specific sets among the settled and pastoralist communities. CONCLUSIONS: Context- and age-specific CFR could ensure adequate levels of more modelled nutrients among settled and pastoralist IYC than among agro-pastoralist communities where use of nutrient-dense foods was limited. Adequacy of all eleven modelled micronutrients was not achievable and additional approaches to ensure adequate diets are required. Consolidated messages should be easier to implement as part of a behaviour change strategy; however, they would likely not achieve the same improvements in population-level dietary adequacy as age-specific CFR.
Assuntos
Aleitamento Materno , Dieta , Transtornos do Crescimento/epidemiologia , Fenômenos Fisiológicos da Nutrição do Lactente , Síndrome de Emaciação/epidemiologia , Estudos Transversais , Feminino , Qualidade dos Alimentos , Abastecimento de Alimentos , Transtornos do Crescimento/prevenção & controle , Humanos , Lactente , Quênia/epidemiologia , Fenômenos Fisiológicos da Nutrição Materna , Rememoração Mental , Micronutrientes/administração & dosagem , Micronutrientes/análise , Avaliação Nutricional , Necessidades Nutricionais , Tamanho da Porção , Inquéritos e Questionários , Síndrome de Emaciação/prevenção & controleRESUMO
OBJECTIVE: To determine the feasibility of distributing micronutrient powders (MNP) for home fortification during biannual Maternal, Neonatal and Child Health Week (MNCHW) events, as a strategy to improve young child nutrition. DESIGN: We evaluated the coverage, delivery, use and adherence of MNP, and associated behaviour change communication (BCC) materials and social mobilization, through cross-sectional surveys of caregivers attending health-service distribution events and health workers involved in MNP distribution, facility-based observations of MNP distribution activities and a repeated survey of caregivers in their homes who received MNP for their child. SETTING: Four Local Government Areas in Benue State, Nigeria. SUBJECTS: Caregivers of children 6-59 months of age attending health-service distribution events. RESULTS: The 8 million MNP delivered in this pilot during three distribution events were estimated to reach about one-third of eligible children in the area at each event. Programme fidelity was limited by shortages of MNP, BCC materials and inadequate social mobilization, with some limitations in health worker training and engagement. MNP use was consistent with the recommended two or three sachets per week among 51-69 % of caregivers surveyed at home. CONCLUSIONS: MNP coverage was low, but consistent with that typically achieved with other services delivered through MNCHW in Benue. Among caregivers who received MNP, acceptance and use among targeted children was high. While some weaknesses in knowledge and delivery of MNP by health workers were observed, health system strengthening and more extensive social mobilization would be key to achieving higher coverage with MNP and other health services provided through MNCHW.
Assuntos
Suplementos Nutricionais , Alimentos Fortificados , Micronutrientes/administração & dosagem , Saúde da Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Saúde do Lactente , Saúde Materna , Nigéria , PósRESUMO
BACKGROUND: Zinc deficiency is prevalent among children and women in Bangladesh and parboiled rice is the major staple food consumed. Parboiling offers an opportunity to increase the zinc and iron content of rice by adding fortificants to the soaking water. RESULTS: Rice zinc content increased with increasing amounts of zinc sulfate added to the parboil soaking water. Addition of 1300 mg zinc L(-1) increased raw polished rice zinc content from 16.6 to 44.9 mg kg(-1) and from 12.6 to 32.9 mg kg(-1) in the open and closed parboiling systems, equivalent to 170% and 161% increases, respectively. Retention of zinc after washing and cooking was 70-81% across all concentrations tested. Addition of iron-ethylenediaminetetraacetic acid and zinc sulfate together increased zinc, but not iron, content of polished rice. The simulated prevalence of inadequate zinc intake was reduced by more than half among children and nearly two-thirds among women if 50% of the population were to consume the 1300 mg zinc L(-1) parboiled fortified rice. CONCLUSION: Addition of zinc sulfate to soaking water during parboiling increases the zinc content of rice and, if found to be bioavailable, could substantially reduce the prevalence of inadequate zinc intake by children and women in Bangladesh.
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Deficiências Nutricionais/prevenção & controle , Manipulação de Alimentos , Alimentos Fortificados , Oryza , Oligoelementos/administração & dosagem , Água , Zinco/administração & dosagem , Bangladesh , Criança , Culinária , Dieta , Humanos , Ferro/administração & dosagem , Necessidades Nutricionais , Sementes , Oligoelementos/deficiência , Oligoelementos/uso terapêutico , Zinco/deficiência , Zinco/uso terapêutico , Sulfato de Zinco/administração & dosagem , Sulfato de Zinco/uso terapêuticoRESUMO
Poor quality infant and young child (IYC) diets contribute to chronic under-nutrition. To design effective IYC nutrition interventions, an understanding of the extent to which realistic food-based strategies can improve dietary adequacy is required. We collected 24-h dietary recalls from children 6-23 months of age (n = 401) in two rural agro-ecological zones of Kenya to assess the nutrient adequacy of their diets. Linear programming analysis (LPA) was used to identify realistic food-based recommendations (FBRs) and to determine the extent to which they could ensure intake adequacy for 12 nutrients. Mean nutrient densities of the IYC diets were below the desired level for four to nine of the 10 nutrients analysed, depending on the age group. Mean dietary diversity scores ranged from 2.1 ± 1.0 among children 6-8 months old in Kitui County to 3.7 ± 1.1 food groups among children 12-23 months old in Vihiga County. LPA confirmed that dietary adequacy for iron, zinc and calcium will be difficult to ensure using only local foods as consumed. FBRs for breastfed children that promote the daily consumption of cows'/goats' milk (added to porridges), fortified cereals, green leafy vegetables, legumes, and meat, fish or eggs, 3-5 times per week can ensure dietary adequacy for nine and seven of 12 nutrients for children 6-11 and 12-23 months old, respectively. For these rural Kenyan children, even though dietary adequacy could be improved via realistic changes in habitual food consumption practices, alternative interventions are needed to ensure dietary adequacy at the population level.
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Cálcio/deficiência , Dieta , Deficiências de Ferro , Desnutrição , População Rural , Zinco/deficiência , Animais , Cálcio da Dieta/administração & dosagem , Inquéritos sobre Dietas , Grão Comestível , Ovos , Feminino , Abastecimento de Alimentos , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Ferro da Dieta/administração & dosagem , Quênia/epidemiologia , Masculino , Desnutrição/epidemiologia , Carne , Leite , Necessidades Nutricionais , Verduras , Zinco/administração & dosagemRESUMO
The few available studies of programme effectiveness in nutrition find that programmes are less effective than would be predicted from the efficacy trials that are the basis for evidence-based programming. Some of these are due to gaps in utilisation within households. To a greater extent, these gaps can be attributed to problems in programme design and implementation. 'Implementation research in nutrition' is an emerging area of study aimed at addressing this problem, by building an evidence base and a sound theory to design and implement programmes that will effectively deliver nutrition interventions. The purpose of this supplement to Maternal & Child Nutrition is to contribute to this growing area of implementation research. The series of papers presented and the reflections for policymaking and programmes, combined with the reflections on the application of ethnography to this area of inquiry, illustrate the value of systematic research undertaken for the purpose of supporting the design of nutrition interventions that are appropriate for the specific populations in which they are undertaken.
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Prática Clínica Baseada em Evidências/métodos , Pesquisa sobre Serviços de Saúde , Desenvolvimento de Programas/métodos , Antropologia Cultural , Criança , Ciências da Nutrição Infantil , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Dieta , Feminino , Implementação de Plano de Saúde , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Quênia , Fenômenos Fisiológicos da Nutrição Materna , Política Nutricional , Avaliação de Programas e Projetos de SaúdeRESUMO
Several types of interventions can be used to improve nutrient intake adequacy in infant and young child (IYC) diets, including fortified foods, home fortification, nutrition education and behaviour change communication (BCC) in addition to agricultural and market-based strategies. However, the appropriate selection of interventions depends on the social, cultural, physical and economic context of the population. Derived from two rural Kenyan populations, this analysis combined information from: (1) a quantitative analysis to derive a set of food-based recommendations (FBRs) to fill nutrient intake gaps in IYC diets and identify 'problem nutrients' for which intake gaps require solutions beyond currently available foods and dietary patterns, and (2) an ethnographic qualitative analysis to identify contextual factors posing opportunities or constraints to implementing the FBRs, including perceptions of cost, convenience, accessibility and appropriateness of the recommended foods for IYC diets and other social or physical factors that determine accessibility of those foods. Opportunities identified included BCC to increase the acceptability and utilisation of green leafy vegetables (GLV) and small fish and agronomic interventions to increase the productivity of GLV and millet. Value chains for millet, beans, GLV, milk and small fish should be studied for opportunities to increase their accessibility in local markets. Processor-level interventions, such as partially cooked fortified dry porridge mixes or unfortified cereal mixes incorporating millet and beans, may increase the accessibility of foods that provide increased amounts of the problem nutrients. Multi-sectoral actors and community stakeholders should be engaged to assess the feasibility of implementing these locally appropriate strategies.
Assuntos
Agricultura/métodos , Alimentos , Fenômenos Fisiológicos da Nutrição do Lactente , Valor Nutritivo , População Rural , Adulto , Animais , Antropologia Cultural , Custos e Análise de Custo , Dieta , Inquéritos sobre Dietas , Grão Comestível , Fabaceae , Peixes , Alimentos/economia , Alimentos Fortificados , Educação em Saúde , Humanos , Lactente , Alimentos Infantis , Quênia , Leite , Milhetes , Política Nutricional , Necessidades Nutricionais , VerdurasRESUMO
Information is needed on zinc absorption from grain cultivars having higher zinc content. Total absorbed zinc (TAZ) from mixed diets containing high-zinc rice (HZnR), conventional rice (CR), or CR plus zinc fortificant (CR+Zn) was measured. Forty-two nonmalnourished preschool-aged children were enrolled in 1 of 2 groups. Using a crossover design, children in group A (n = 22) received for 1 d each a mixed diet containing 150 g CR or HZnR. Children in group B (n = 20) received HZnR on 1 d and CR+Zn on the other day. Fractional zinc absorption (FZA) was measured during each dietary period by using a dual-isotope tracer ratio technique; TAZ was calculated as the product of zinc intake [total dietary zinc (TDZ)] and FZA. TDZ was 3.83, 4.83, and 6.03 mg/d when the children were fed the CR, HZnR, and CR+Zn-containing diets, respectively. Mean FZA from the CR diet was greater than from the HZnR diet (25.1 vs. 20.1%, P < 0.001), and the mean FZA from the CR+Zn diet (18.8%) was less than from both the CR diet (P < 0.001) and the HZnR diet (P = 0.014). The mean TAZ was 0.96 ± 0.16, 0.97 ± 0.18, and 1.13 ± 0.20 mg/d from the CR, HZnR and CR +Zn diets, respectively. TAZ was not different for the CR and HZnR diets (P = 0.99) but was significantly greater from the CR+Zn diet compared with the other 2 diets (P < 0.001). Rice cultivars with higher zinc and/or lower phytate content are needed to increase TAZ by young children consuming this amount of rice.
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Alimentos Fortificados , Oryza/química , Zinco/farmacocinética , Bangladesh , Disponibilidade Biológica , Pré-Escolar , Estudos Cross-Over , Dieta , Feminino , Humanos , Masculino , Sementes/química , Zinco/administração & dosagem , Zinco/deficiência , Isótopos de Zinco/urinaRESUMO
Documentation of micronutrient intake inadequacies among developing country populations is important for planning interventions to control micronutrient deficiencies. The objective of this study was to quantify micronutrient intakes by young children and their primary female caregivers in rural Bangladesh. We measured 24-h dietary intakes on 2 nonconsecutive days in a representative sample of 480 children (ages 24-48 mo) and women in 2 subdistricts of northern Bangladesh by using 12-h weighed food records and subsequent 12-h recall in homes. We calculated the probability of adequacy (PA) of usual intakes of 11 micronutrients and an overall mean PA, and evaluated dietary diversity by counting the total number of 9 food groups consumed. The overall adequacy of micronutrient intakes was compared to dietary diversity scores using correlation and multivariate regression analyses. The overall mean prevalence of adequacy of micronutrient intakes for children was 43% and for women was 26%. For children, the prevalence of adequate intakes for each of the 11 micronutrients ranged from a mean of 0 for calcium to 95% for vitamin B-6 and was <50% for iron, calcium, riboflavin, folate, and vitamin B-12. For women, mean or median adequacy was <50% for all nutrients except vitamin B-6 and niacin and was <1% for calcium, vitamin A, riboflavin, folate, and vitamin B-12. The mean PA (MPA) was correlated with energy intake and dietary diversity, and multivariate models including these variables explained 71-76% of the variance in MPA. The degree of micronutrient inadequacy among young children and women in rural Bangladesh is alarming and is primarily explained by diets low in energy and little diversity of foods.
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Dieta/efeitos adversos , Abastecimento de Alimentos , Micronutrientes/administração & dosagem , Saúde da População Rural , Adulto , Bangladesh/epidemiologia , Cuidadores , Pré-Escolar , Estudos Transversais , Países em Desenvolvimento , Dieta/economia , Dieta/etnologia , Registros de Dieta , Feminino , Abastecimento de Alimentos/economia , Humanos , Masculino , Micronutrientes/deficiência , Micronutrientes/economia , Niacina/administração & dosagem , Niacina/deficiência , Niacina/economia , Inquéritos Nutricionais , Prevalência , Saúde da População Rural/economia , Saúde da População Rural/etnologia , Deficiência de Vitamina B 6/economia , Deficiência de Vitamina B 6/epidemiologia , Deficiência de Vitamina B 6/etnologia , Deficiência de Vitamina B 6/etiologia , Adulto JovemRESUMO
Vitamin A deficiency (VAD) persists in Uganda and the consumption of ß-carotene-rich orange sweet potato (OSP) may help to alleviate it. Two large-scale, 2-y intervention programs were implemented among Ugandan farmer households to promote the production and consumption of OSP. The programs differed in their inputs during year 2, with one being more intensive (IP) and the other being reduced (RP). A randomized, controlled effectiveness study compared the impact of the IP and RP with a control on OSP and vitamin A intakes among children aged 6-35 mo (n = 265) and 3-5 y (n = 578), and women (n = 573), and IP compared with control on vitamin A status of 3- to 5-y-old children (n = 891) and women (n = 939) with serum retinol <1.05 µmol/L at baseline. The net OSP intake increased in both the IP and RP groups (P < 0.01), accounting for 44-60% of vitamin A intake at follow-up. The prevalence of inadequate vitamin A intake was reduced in the IP and RP groups compared with controls among children 6-35 mo of age (>30 percentage points) and women (>25 percentage points) (P < 0.01), with no differences between the IP and RP groups of children (P = 0.75) or women (P = 0.17). There was a 9.5 percentage point reduction in prevalence of serum retinol <1.05 µmol/L for children with complete data on confounding factors (n = 396; P < 0.05). At follow-up, vitamin A intake from OSP was positively associated with vitamin A status (P < 0.05). Introduction of OSP to Ugandan farming households increased vitamin A intakes among children and women and was associated with improved vitamin A status among children.
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Ipomoea batatas/química , Deficiência de Vitamina A/epidemiologia , Vitamina A/administração & dosagem , beta Caroteno/administração & dosagem , Adulto , Antropometria , Pré-Escolar , Estudos Transversais , Características da Família , Feminino , Seguimentos , Humanos , Lactente , Masculino , Avaliação Nutricional , Estado Nutricional , Análise de Regressão , População Rural , Uganda/epidemiologia , Vitamina A/sangue , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/tratamento farmacológicoRESUMO
ß-Carotene-rich orange sweet potato (OSP) has been shown to improve vitamin A status of infants and young children in controlled efficacy trials and in a small-scale effectiveness study with intensive exposure to project inputs. However, the potential of this important food crop to reduce the risk of vitamin A deficiency in deficient populations will depend on the ability to distribute OSP vines and promote its household production and consumption on a large scale. In rural Mozambique, we conducted a randomised, controlled effectiveness study of a large-scale intervention to promote household-level OSP production and consumption using integrated agricultural, demand creation/behaviour change and marketing components. The following two intervention models were compared: a low-intensity (1 year) and a high-intensity (nearly 3 years) training model. The primary nutrition outcomes were OSP and vitamin A intakes by children 6-35 months and 3-5·5 years of age, and women. The intervention resulted in significant net increases in OSP intakes (model 1: 46, 48 and 97 g/d) and vitamin A intakes (model 1: 263, 254 and 492 µg retinol activity equivalents/d) among the younger children, older children and women, respectively. OSP accounted for 47-60 % of all sweet potato consumed and, among reference children, provided 80 % of total vitamin A intakes. A similar magnitude of impact was observed for both models, suggesting that group-level trainings in nutrition and agriculture could be limited to the first project year without compromising impact. Introduction of OSP to rural, sweet potato-producing communities in Mozambique is an effective way to improve vitamin A intakes.
Assuntos
Ipomoea batatas/química , Deficiência de Vitamina A/dietoterapia , Vitamina A/administração & dosagem , Adulto , Pré-Escolar , Cor , Produtos Agrícolas , Países em Desenvolvimento , Dieta , Inquéritos sobre Dietas , Comportamento Alimentar , Feminino , Humanos , Lactente , Masculino , Moçambique , Estado Nutricional , População Rural , Vitamina A/química , Vitamina A/farmacologia , Deficiência de Vitamina A/prevenção & controleRESUMO
OBJECTIVE: To determine the prevalence of vitamin A deficiency, infection and adequacy of vitamin A intakes among Zambian children, and the contribution of dietary vitamin A and infection to vitamin A status. DESIGN: A cross-sectional survey of vitamin A intakes by the 24 h recall method, vitamin A status by plasma retinol and the modified relative dose-response test, and infection by acute-phase proteins. SETTING: Rural communities in Central and Eastern Provinces of Zambia. SUBJECTS: Children 2-5 years of age. RESULTS: The prevalence of vitamin A deficiency was 56 % by plasma retinol, 48 % with infection-adjusted plasma retinol and 22 % by the modified relative dose-response test. The majority of children (61 %) had a current infection. Vitamin A intakes were relatively high (331 to 585 µg retinol activity equivalents/d in the harvest/early post-harvest and late post-harvest seasons, respectively) and the prevalence of inadequate intakes was <1 % when compared with the Estimated Average Requirement (210 and 275 µg retinol activity equivalents/d for children aged 1-3 and 4-8 years, respectively). Elevated α-1-acid glycoprotein was negatively associated with plasma retinol (P < 0·0 0 1) and vitamin A intake was positively associated with plasma retinol (P < 0·05), but only when estimated assuming a 26:1 retinol equivalence for provitamin A from green and yellow vegetables. CONCLUSIONS: Infection and vitamin A intakes were significant determinants of plasma retinol. We cannot conclude which indicator more accurately represents the true vitamin A status of the population. Reasons for the persistent high prevalence of vitamin A deficiency in the presence of adequate vitamin A intakes are unclear, but the high rates of infection may play a role.
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Deficiência de Vitamina A/epidemiologia , Vitamina A/administração & dosagem , Vitamina A/sangue , Proteínas de Fase Aguda/análise , Proteínas de Fase Aguda/metabolismo , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Estudos Transversais , Dieta , Feminino , Humanos , Infecções/sangue , Masculino , Orosomucoide/análise , Análise de Regressão , População Rural , Verduras , Deficiência de Vitamina A/sangue , Zâmbia/epidemiologiaRESUMO
BACKGROUND: Vitamin A deficiency is associated with poor health outcomes related to reproduction, growth, vision, and immunity. Biofortification of staple crops is a novel strategy for combating vitamin A deficiency in high-risk populations where staple food intakes are high. African populations are proposed beneficiaries of maize (Zea mays) biofortified with provitamin A carotenoids, often called "orange maize" because of its distinctive deep yellow-orange kernels. The color facilitates ready recognition but presents a cultural challenge to maize-consuming populations, including those in much of Africa, who traditionally eat white varieties. OBJECTIVE: This study explores the intake patterns of, as well as adaptation to, traditional foods made with provitamin A-biofortified maize compared with white maize in rural Zambian children 3 to 5 years of age (n = 189) during a 3-month feeding trial. METHODS: The subjects were fed a breakfast of maize porridge (sweet mush), a lunch of maize nshima (stiff mush) with various side dishes, and an afternoon snack based on a 6-day rotating menu. The trial was conducted in 2010. The orange maize used in the trial came from three different sources. O1 maize was from the 2009 harvest and was stored in a freezer until use in 2010. O2 maize was also from the 2009 harvest and was stored in a cold room until 2010. O3 ("fresh") maize was from the 2010 harvest and was fed immediately after harvest in week 9 of the study and then stored in a freezer until milling for the final four weeks. RESULTS: Consumption of menu items, except snacks, was influenced by week (p < .0084). The intakes of porridge and nshima made with orange maize equaled those of porridge and nshima made with white maize from week 2 onward. The intakes of porridge and nshima prepared from O1 and O2 did not differ, but intakes became significantly higher when meals made from O3 were introduced (p < .014 for porridge and p < or = .013 for nshima). CONCLUSIONS: These results demonstrate quick adaptation to orange maize, a preference for recently harvested maize, and an optimistic outlook for similar adaptation patterns in other biofortified-maize target countries.
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Carotenoides/metabolismo , Dieta , Preferências Alimentares , Alimentos Geneticamente Modificados , Pigmentos Biológicos/metabolismo , Sementes/metabolismo , Zea mays/metabolismo , Carotenoides/administração & dosagem , Comportamento Infantil/etnologia , Pré-Escolar , Serviços de Saúde Comunitária , Condimentos/análise , Dieta/etnologia , Grão Comestível/química , Fast Foods/análise , Manipulação de Alimentos , Preferências Alimentares/etnologia , Serviços de Alimentação , Promoção da Saúde , Humanos , Saúde da População Rural , Sementes/química , Deficiência de Vitamina A/prevenção & controle , Zâmbia , Zea mays/químicaRESUMO
BACKGROUND: The density of minerals and vitamins in food staples eaten widely by the poor may be increased either through conventional plant breeding or through the use of transgenic techniques, a process known as biofortification. OBJECTIVE: HarvestPlus seeks to develop and distribute varieties of food staples (rice, wheat, maize, cassava, pearl millet, beans, and sweet potato) that are high in iron, zinc, and provitamin A through an interdisciplinary, global alliance of scientific institutions and implementing agencies in developing and developed countries. METHODS: In broad terms, three things must happen for biofortification to be successful. First, the breeding must be successful--high nutrient density must be combined with high yields and high profitability. Second, efficacy must be demonstrated--the micronutrient status of human subjects must be shown to improve when they are consuming the biofortified varieties as normally eaten. Thus, sufficient nutrients must be retained in processing and cooking and these nutrients must be sufficiently bioavailable. Third, the biofortified crops must be adopted by farmers and consumed by those suffering from micronutrient malnutrition in significant numbers. RESULTS: Biofortified crops offer a rural-based intervention that, by design, initially reaches these more remote populations, which comprise a majority of the undernourished in many countries, and then penetrates to urban populations as production surpluses are marketed. In this way, biofortification complements fortification and supplementation programs, which work best in centralized urban areas and then reach into rural areas with good infrastructure. CONCLUSIONS: Initial investments in agricultural research at a central location can generate high recurrent benefits at low cost as adapted, biofortified varieties become available in country after country across time at low recurrent costs.
Assuntos
Produtos Agrícolas/química , Alimentos Fortificados/economia , Micronutrientes/deficiência , Sementes/química , Deficiência de Vitamina A/epidemiologia , Disponibilidade Biológica , Cruzamento , Análise Custo-Benefício , Produtos Agrícolas/economia , Produtos Agrícolas/genética , Países em Desenvolvimento , Variação Genética , Humanos , Ferro/farmacocinética , Deficiências de Ferro , Micronutrientes/administração & dosagem , Plantas Geneticamente Modificadas , Prevalência , População Rural , Sementes/genética , Zinco/deficiência , Zinco/farmacocinéticaRESUMO
Rural Bangladeshi populations have a high risk of zinc deficiency due to their consumption of a predominantly rice-based diet with few animal-source foods. Breeding rice for higher zinc content would offer a sustainable approach to increase the population's zinc intakes. The objectives of the study were to quantify usual rice and zinc intakes in young children and their adult female primary caregivers and to simulate the potential impact of zinc-biofortified rice on their zinc intakes. We measured dietary intake in a representative sample of 480 children (ages 24-48 mo) and their female caregivers residing in 2 rural districts of northern Bangladesh. Dietary intakes were estimated by 12-h weighed records and 12-h recall in homes on 2 nonconsecutive days. Serum zinc concentrations were determined in a subsample of children. The median (25th, 75th percentile) rice intakes of children and female caregivers were 134 (99, 172) and 420 (365, 476) g raw weight/d, respectively. The median zinc intakes were 2.5 (2.1, 2.9) and 5.4 (4.8, 6.1) mg/d in children and women, respectively. Twenty-four percent of children had low serum zinc concentrations ( < 9.9 micromol/L) after adjusting for elevated acute phase proteins. Rice was the main source of zinc intake, providing 49 and 69% of dietary zinc to children and women, respectively. The prevalence of inadequate zinc intakes was high in both the children (22%) and women (73-100%). Simulated increases in rice zinc content to levels currently achievable through selective breeding decreased the estimated prevalence of inadequacy to 9% in children and 20-85% in women, depending on the assumptions used to estimate absorption. Rural Bangladeshi children and women have inadequate intakes of zinc. Zinc biofortification of rice has the potential to markedly improve the zinc adequacy of their diets.
Assuntos
Deficiências Nutricionais/prevenção & controle , Alimentos Fortificados/análise , Oryza/química , Zinco/administração & dosagem , Zinco/deficiência , Adulto , Bangladesh/epidemiologia , Pré-Escolar , Estudos Transversais , Deficiências Nutricionais/epidemiologia , Dieta , Inquéritos sobre Dietas , Feminino , Habitação , Humanos , Masculino , Estado Nutricional , Prevalência , População Rural , Adulto Jovem , Zinco/sangueRESUMO
Biofortification of crops that provide major food staples to large, poor rural populations offers an appealing strategy for diminishing public health problems attributable to micronutrient deficiencies. The objective of this first-stage human study was to determine the increase in quantity of zinc (Zn) absorbed achieved by biofortifying wheat with Zn. Secondary objectives included evaluating the magnitude of the measured increases in Zn absorption as a function of dietary Zn and phytate. The biofortified and control wheats were extracted at high (95%) and moderate (80%) levels and Zn and phytate concentrations measured. Adult women with habitual diets high in phytate consumed 300 g of 95 or 80% extracted wheat as tortillas for 2 consecutive days using either biofortified (41 mg Zn/g) or control (24 mg Zn/g) wheat. All meals for the 2-d experiment were extrinsically labeled with Zn stable isotopes and fractional absorption of Zn determined by a dual isotope tracer ratio technique. Zn intake from the biofortified wheat diet was 5.7 mg/d (72%) higher at 95% extraction (P < 0.001) and 2.7 mg/d (68%) higher at 80% extraction compared with the corresponding control wheat (P = 0.007). Zn absorption from biofortified wheat meals was (mean +/- SD) 2.1 +/- 0.7 and 2.0 +/- 0.4 mg/d for 95 and 80% extraction, respectively, both of which were 0.5 mg/d higher than for the corresponding control wheat (P < 0.05). Results were consistent with those predicted by a trivariate model of Zn absorption as a function of dietary Zn and phytate. Potentially valuable increases in Zn absorption can be achieved from biofortification of wheat with Zn.
Assuntos
Farinha/análise , Alimentos Fortificados/análise , Triticum/química , Zinco/química , Zinco/metabolismo , Adolescente , Adulto , Estudos Transversais , Suplementos Nutricionais , Feminino , Humanos , México , Adulto Jovem , Zinco/urina , Isótopos de ZincoRESUMO
Biofortification is an agricultural strategy that aims to increase the content of select micronutrients, including zinc, in staple food crops such as rice, wheat, maize, pearl millet, and others. When consumed among zinc-deficient populations, zinc-biofortified staple foods should improve the adequacy of zinc intakes and hence reduce the risk of dietary zinc deficiency. Several conditioning factors will contribute to the potential for this strategy to meet its goal, including the additional amount of zinc that can be bred into the staple crop food, the amount of zinc that remains in the staple crop food following usual processing methods, and the bioavailability of zinc from the staple crop food in the context of the usual diet. Reduction of the phytate content of cereals with the use of agricultural techniques is a potential complementary strategy for improving the bioavailability of zinc. The feasibility of biofortification to result in a meaningful increase in the adequacy of population zinc intakes and to reduce the consequences of zinc deficiencies still needs to be determined through efficacy trials. At the program level, the ability to widely disseminate biofortified crop varieties and the willingness of farmers to adopt them will also affect the magnitude of the impact of this strategy.
Assuntos
Produtos Agrícolas , Alimentos Fortificados , Estado Nutricional , Oligoelementos/administração & dosagem , Zinco/administração & dosagem , Agricultura , Disponibilidade Biológica , Dieta , Manipulação de Alimentos , Humanos , Necessidades Nutricionais , Ácido Fítico/efeitos adversos , Oligoelementos/deficiência , Zinco/deficiênciaRESUMO
Zinc deficiency increases the risk and severity of a variety of infections, restricts physical growth, and affects specific outcomes of pregnancy. Global recognition of the importance of zinc nutrition in public health has expanded dramatically in recent years, and more experience has accumulated on the design and implementation of zinc intervention programs. Therefore, the Steering Committee of the International Zinc Nutrition Consultative Group (IZiNCG) completed a second IZiNCG technical document that reexamines the latest information on the intervention strategies that have been developed to enhance zinc nutrition and control zinc deficiency. In particular, the document reviews the current evidence regarding preventive zinc supplementation and the role of zinc as adjunctive therapy for selected infections, zinc fortification, and dietary diversification or modification strategies, including the promotion and protection of breastfeeding and biofortification. The purposes of this introductory paper are to summarize new guidelines on the assessment of population zinc status, as recommended by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF), the International Atomic Energy Agency (IAEA), and IZiNCG, and to provide an overview on several new advances in zinc metabolism. The following papers will then review the intervention strategies individually.
Assuntos
Avaliação Nutricional , Estado Nutricional , Oligoelementos/deficiência , Zinco/deficiência , Humanos , Guias de Prática Clínica como Assunto , Fatores de Risco , Oligoelementos/metabolismo , Zinco/metabolismoRESUMO
Semi-quantitative dietary assessment methods are frequently used in low income countries, and the use of photographic series for portion size estimation is gaining popularity. However, when adequate data on commonly consumed foods and portion sizes are not available to design these tools, alternative data sources are needed. This study aimed to develop and test methods to: (i) identify foods likely to be consumed in a study population in rural Uganda, and; (ii) to derive distributions of portion sizes for common foods and dishes. A process was designed to derive detailed food and recipe lists using guided group interviews with women from the survey population, including a score for the likelihood of foods being consumed. A rapid recall method for portion size distribution estimation (PSDE) using direct weight by a representative sample of the survey population was designed and implemented. Results were compared to data from a 24 hour dietary recall (24HR). Of the 82 food items reported in the 24HR survey, 87% were among those scored with a high or medium likelihood of being consumed and accounted for 95% of kilocalories. Of the most frequently reported foods in the 24HR, portion sizes for many (15/25), but not all foods did not differ significantly (p<0.05) from those in the portion size estimation method. The percent of portion sizes reported in the 24 hour recall falling between the 5th and 95th percentiles as determined by the PSDE method ranged from 18% up to 100%. In conclusion, a simple food listing and scoring method effectively identified foods most likely to occur in a dietary survey. A novel PSDE method produced similar estimates as for the 24HR, while the approach for others should be further considered and validated. These methods are an improvement on those in current use.
Assuntos
Peso Corporal , Inquéritos sobre Dietas , Avaliação Nutricional , Tamanho da Porção , Adulto , Feminino , Humanos , Masculino , UgandaRESUMO
Eight in ten female readymade garment (RMG) workers in Bangladesh suffer from anemia, a condition which damages both health and productivity. This study evaluated the effectiveness of a workplace nutrition program on anemia reduction in female RMG workers of Bangladesh. A quasi-experimental mixed method study was conducted on 1310 non-pregnant female RMG workers from four factories. Two types of intervention packages (A and C) were tested against their respective controls (B and D) over a 10-month period. Among factories that already provided lunch to workers with regular behavior change counseling (BCC), one intervention (A) and one control (B) factory were selected, and among factories that did not provide lunches to their workers but provided regular BCC, one intervention (C) and one control (D) factory were selected: (A) Lunch meal intervention package: daily nutritionally-enhanced (with fortified rice) hot lunch, once weekly iron-folic acid (IFA) supplement and monthly enhanced (with nutrition module) behavior change counseling (BCC) versus (B) Lunch meal control package: regular lunch and BCC; and (C) Non-meal intervention package: twice-weekly IFA and enhanced BCC versus (D) Non-meal control package: BCC alone. Body weight and capillary hemoglobin were measured. Changes in anemia prevalence were estimated by difference-in-difference (DID) method. Thematic analysis of qualitative in-depth interviews with RMG workers was performed and findings were triangulated. Anemia was reduced significantly in both lunch meal and non-meal intervention (A and C) group (DID: 32 and 12 percentage points, p: <0.001 and <0.05 respectively). The mean hemoglobin concentration also significantly increased by 1 gm/dL and 0.4 gm/dL in both A and C group (p: <0.001 respectively). Weight did not change in the intervention groups (A and C) but significantly increased by more than 1.5 kg in the comparison groups (B and D). The knowledge of different vitamin and mineral containing foods and their benefits was increased significantly among all participants. Workplace nutrition programs can reduce anemia in female RMG workers, with the greatest benefits observed when both nutritionally enhanced lunches and IFA supplements are provided.