Active clinical trials for "Vitamin A Deficiency"

The WHO recommended intermittent iron supplementation as a strategy for prevention of anemia and iron deficiency among school age children. Several aspects of cognitive development, co-supplementation with other micronutrients, severe adverse events especially in the context of malaria were missing. The investigators will evaluate the effectiveness of intermittent iron and vitamin A supplementation on cognitive development and anemia and iron status of Rural Ethiopian school children.

The purpose of this study is to evaluate the effect of maternal supplementation with 400,000 IU of oral retinol palmitate in the post-partum, the nutritional situation of the binomial mother-child, on growth and morbidity of children in breastfeeding in the first six months of life.

Vitamin A is an essential micronutrient for the normal functioning of the visual system, growth and development, immunity and reproduction. Its deficiency causes anemia, growth retardation and xerophthalmia. Vitamin A deficiency also increases the incidence and/or severity of infectious episodes and affects child survival. Reduced child survival is the most severe and potentially the most widespread consequence of Vitamin A deficiency. Improvement in vitamin A status is now regarded as one of the most cost effective preventive measures for the reduction of child mortality and morbidity. Over the past decade several studies have examined the effect of vitamin A on reducing mortality among children aged ≥6months at the time of intervention. Impact of vitamin A supplementation can significantly reduce total mortality but it is only established through supplementation programs in children age 6 months or older. It was assumed that breast milk protects infants from vitamin A deficiency, but recent evidence has challenged this. Infants born with low stores of vitamin A and if the mother breast milk has a low concentration of vitamin A, as found in developing countries, the infants might be unable to meet their daily requirements and improve body reserves. There is association between mortality and degree of vitamin A deficiency, greater the degree of deficiency, higher the mortality. The role of vitamin A in child survival is now well established and over 60 countries have vitamin A supplementation programs nationally. However, most are still using vitamin A supplements in the second half of infancy, even though over 75% of all under 5 deaths take place in the first 6 months of life. If neonatal vitamin A supplementation can be found to be effective and a service delivery mechanism also found, this will represent a major advance in reaching the MDG 4 targets. This is thus persuasive reason to explore this particular preventive strategy, especially in terms of packaging with other postnatal care activities. However, given that in some instances it has been difficult to disentangle the effect of vitamin A dosing from concomitant vaccinations such as BCG, the current evidence needs further evaluation in effectiveness settings. We propose to evaluate the effectiveness of early neonatal vitamin A administration (single dose 50,000 units) to the newborn to see its effect on infant mortality less than 6 months of age as part of postnatal package through National Program. Government has launched the National Program for Family Planning and Primary Health Care since April 1994. Primarily it is being implemented in the community through Lady Health Workers (LHWs) of the National Program. The LHWs are females, with a minimum of eight years of education, residents of the locality in which they are working. The Programme is being currently implemented in all the districts throughout the country and 93,000 LHWs are working covering primarily women and children of the rural population. These LHWs deliver services related to family planning, maternal and child health, immunization, nutrition and treatment of minor ailments to her average registered population of 100-150 households or ~1000 population. Over 3,000 Supervisors have been recruited and trained to supervise the work of LHWs.

Vitamin A supplementation at birth may increase survival of infants through one year of age by reducing mortality from infectious diseases, though current studies are not conclusive on this point. The goal of our study is to determine if supplementation of newborn infants with 50,000 IU of vitamin A improves aspects of immune function that may be impaired by vitamin A deficiency. Our underlying assumption is that supplementation may thus decrease risk of death by improving immune function and the ability to survive infections. This project will be limited to the examination of the impact of vitamin A on immune function and will not aim to determine the impact on morbidity or mortality, which would require larger sample sizes. The hypotheses addressed by this study are as follows: Provision of vitamin A supplements to newborns at risk of vitamin A deficiency will (1) improve functioning of the thymus (the source of T lymphocytes, cells of the immune system that are important in response to infection and immunization); (2) enhance T lymphocyte-mediated responses to standard vaccines given at birth and early in infancy; and (3) improve gut barrier function (i.e., ability to prevent bacterial infection across the epithelial barrier), relative to provision of a placebo.

The combination of infectious diseases and malnutrition is the most prevalent, preventable public health problem in the world, responsible for millions of deaths annually, particularly in infants and children. Approximately 13 million children die each year in developing countries from infectious diseases, with the majority of these deaths related to malnutrition. The relationship between infections and malnutrition is synergistic, each further compromising the outcome of the other. Malnutrition compromises natural immunity leading to increased susceptibility to infections, more frequent and prolonged disease episodes, and increased severity of disease. Likewise, infections can aggravate or precipitate malnutrition through decreased appetite and food intake, nutrient malabsorption, nutrient loss or increased metabolic needs. Another issue is that infections (as well as overweight and obesity status) affect nutritional biomarkers making it difficult to assess the real magnitude of some nutritional problems. This is the case of vitamin A. Vitamin A deficiency is defined to be of severe public health importance if 20% or more of a defined population has a serum retinol concentration of less than 0.7 µmol/L. However, circulating concentrations of serum retinol are reduced by infections and in such situations serum retinol concentration is not a good indicator of vitamin A status. Serum acute-phase proteins can indicate the severity and duration of an infection. Correcting vitamin A deficiency is addressed in Ethiopia through vitamin A supplementation of children, dietary diversity and using bio-fortified foods. However, assessing vitamin A status, and the effectiveness of government interventions, is challenging in settings where infectious diseases are endemic, as in most area of the country. Evaluation of vitamin A status is relatively insensitive when based on changes in serum retinol concentrations, which are homeostatically controlled and negatively affected by subclinical infections. Liver stores of vitamin A, the best indicator of vitamin A status, cannot be routinely evaluated. The isotope dilution technique is the preferred method for determining vitamin A status and assessing the efficacy and effectiveness of intervention programs aimed at improving vitamin A status. It is the only indirect assessment method that provides a quantitative estimate of vitamin A status across the continuum of deficient to excessive stores.

Our objectives will be to test the following hypotheses and to make the following determinations: (1) The absorption and bio-conversion of provitamin A carotenes taken by children are different between spinach, Golden Rice, and ß-C in oil capsules. (2) The absorption of provitamin A carotenes and their bioconversion to vitamin A are different in children with or without adequate vitamin A nutrition. (3) To define the vitamin A equivalence(s) of dietary spinach, Golden Rice, and a ß-C in oil dose by using an isotope reference method in children with or without adequate vitamin A nutrition and to compare those values with values derived from model based compartmental analysis. (4) To determine the number and time of blood samples needed for future studies in various field settings on the retinol equivalence of a large number of plant sources.

The purpose of this study is to determine the vitamin A equivalents in high-carotenoid varieties of cassava.

The goal of the research study is to determine the absorption, metabolism, and bioconversion of carotenoids such as beta-carotene to vitamin A from gari made with biofortified cassava compared to a mixture of red palm oil and gari made from typical white cassava.

Summary: Chronic intake of foods low in vitamin A (retinol) and provitamin A forming an unbalanced diet with little variety is common in young individuals in the United Kingdom (UK) population and can lead to subclinical micronutrient deficiency. Provitamin A sources such as β-carotene are cleaved centrally by the β-carotene 15,15'-monooxygenase (BCMO1) into retinal, the precursor of retinol. However, the amount of β-carotene and retinol produced after ingestion of β-carotene is highly variable between healthy individuals, with approximately 40% of the subjects being classified as low responders. Several stable isotope studies have shown a large disparity between the most efficient converters and the most inefficient converters of β-carotene with variations of up to 8-fold. It is possible that differences in β-carotene response may be due to single nucleotide polymorphisms (SNPs) in genes involved in aspects of β-carotene conversion. Previous work has shown that carriers of both, the 379V and 267S+379V BCMO1 variant alleles had a reduced ability to convert β-carotene. More importantly, 44% of the western population have the 379V haplotype. A high percentage of the Western population may therefore not be able to achieve adequate vitamin A intake if dietary β-carotene is a major source of their vitamin A intake. This is of particular relevance to vegetarians, to young individuals aged 19-24 years who have lower intakes of preformed retinol than any other age group, and to pregnant women. The aim of this study is to establish whether the maximum recommended dose for β-carotene of 7mg/day by the British Expert Committee on Vitamins and Minerals (EVM) can overcome the SNP effect in the BCMO1 enzyme. Hypothesis: The investigators hypothesize that the current maximum recommended intake of 7 mg of β-carotene per day cannot overcome the low convertor phenotype in BCMO1 to fulfill vitamin A requirements in these people.

Retinol and retinol binding protein were studied in the umbilical cord blood of 44 preterm infants with gestation age of < 30 weeks. Serum retinol and RBP levels were determined by enzyme-linked immunosorbent assay. The rate of transplacental retinol passage was calculated. The demographic data of mother and baby, vitamin use in the mother, antenatal steroid application and diseases diagnosed during pregnancy were recorded. An evaluation was made of the retinol, RBP and factors of the mother and baby affecting the transplacental retinol passage. The relationship between retinol and retinol binding protein levels and neonatal mortality and morbidity was investigated.