Research
Vitamin A
146 peer-reviewed studies curated from PubMed and Semantic Scholar.
Studies
Sorted by quality and recency
Integration of azithromycin mass administration to 1-11-month-old children into an existing health platform to reduce child mortality: a cluster-randomised trial in Burkina Faso.
Cluster-randomised trial in Burkina Faso assessing azithromycin mass drug administration to 1-11-month-old children integrated with vitamin A delivery. The trial found no significant difference in mortality rates between azithromycin and placebo groups, suggesting no effect of azithromycin distribution on infant mortality.
Interventions to Prevent Post-Discharge Mortality among Children in Sub-Saharan Africa: A Systematic Review.
Systematic review evaluating interventions to prevent post-discharge mortality among children in sub-Saharan Africa. Vitamin A supplementation for children with pneumonia showed a statistically significant reduction in post-discharge mortality. Other interventions included supplemental feeding, kangaroo mother care, and micronutrient supplementation, with varying effectiveness.
Different doses of vitamin A supplementation as adjuvant treatment for pneumonia in children: a network meta-analysis of randomized controlled trials.
Network meta-analysis of 25 trials involving 3116 children with pneumonia, assessing different doses of vitamin A supplementation. Medium-dose vitamin A was most effective in reducing fever and cough duration, with low-to-medium doses showing better clinical outcomes than high-dose regimens. Safety outcomes were limited and inconclusive.
Effects of neonatal Vitamin A supplementation on response to vaccinations in early infancy.
A randomized, placebo-controlled trial in 306 infants in Dhaka, Bangladesh evaluated the effect of neonatal Vitamin A supplementation on vaccine responses. Vitamin A increased the delayed-type hypersensitivity response to BCG in infants above the birthweight median but did not affect antibody responses to OPV, TT, and HBV. It affected CD4 T-cell function, with some effects being sex-specific.
Acute management of measles: A systematic review of therapeutic strategies.
This systematic review analyzes therapeutic strategies for acute measles management, highlighting vitamin A supplementation as a widely recommended therapy with strong evidence for reducing morbidity and mortality, especially in children with deficiency. Other treatments like ribavirin, interferon-α, and traditional Chinese medications show potential but require further validation.
Vitamin A supplementation coverage and its associated factors among children 6-59 months of age in Ethiopia: a systematic review and meta-analysis.
This systematic review and meta-analysis assessed vitamin A supplementation coverage and associated factors among children aged 6-59 months in Ethiopia. The pooled vitamin A supplementation coverage was found to be 54.88%, which is below the WHO's recommendation of 80%. Factors such as antenatal care, postnatal care, delivery at health facilities, media exposure, and parental education were associated with increased vitamin A supplementation.
Vitamin A supplementation coverage and associated factors among Ethiopian children under five years: a systematic review and meta-analysis.
This systematic review and meta-analysis assessed vitamin A supplementation coverage among Ethiopian children under five years, finding an overall coverage of 53.43%. Factors associated with coverage included family wealth, maternal antenatal care visits, access to vitamin A information, and maternal education. The study highlights the need for improved interventions to meet national and international supplementation targets.
Serum Vitamin A Is Associated with Variations in the Relationship between Plasma B6 Vitamers and Cardiovascular Disease Risk.
Cohort study of 4091 patients undergoing coronary angiography to explore the association of plasma B6 vitamers with AMI risk according to vitamin A levels. Low plasma PLP and high PA/PL ratio were linked to increased AMI risk, particularly in patients with high vitamin A concentrations.
Selected laboratory-based biomarkers for assessing vitamin A deficiency in at-risk individuals.
This meta-analysis evaluated the accuracy of various biomarkers for assessing vitamin A deficiency in at-risk individuals. The study found that methods to determine vitamin A deficiency had generally low sensitivity (0% to 54%) and high specificity (74% to 94%). The authors caution that no included studies were designed as diagnostic test accuracy studies.
Effects of primary or secondary prevention with vitamin A supplementation on clinically important outcomes: a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis.
This systematic review and meta-analysis evaluated the preventive effects of vitamin A supplements versus placebo or no intervention on clinically important outcomes. It included 120 randomised trials with 1,671,672 participants. Vitamin A did not reduce mortality in individually randomised trials but showed a reduction in mortality in cluster randomised trials, though with very low certainty. No serious adverse events or quality of life impacts were reported.
Oral vitamin A supplements to prevent acute upper respiratory tract infections in children up to seven years of age.
Meta-analysis of six studies with 27,351 participants assessing vitamin A supplementation for preventing acute upper respiratory tract infections (URTIs) in children up to seven years of age. The evidence is uncertain, with low-certainty findings suggesting no significant benefit of vitamin A supplementation in preventing acute URTIs.
Early postnatal high-dose fat-soluble enteral vitamin A supplementation for moderate or severe bronchopulmonary dysplasia or death in extremely low birthweight infants (NeoVitaA): a multicentre, randomised, parallel-group, double-blind, placebo-controlled, investigator-initiated phase 3 trial.
This multicentre, randomised, double-blind, placebo-controlled phase 3 trial assessed the effect of high-dose enteral vitamin A supplementation on moderate or severe bronchopulmonary dysplasia or death in extremely low birthweight infants. The study found that high-dose vitamin A supplementation was safe but did not change the rate of bronchopulmonary dysplasia or death compared to placebo.
Study on serum vitamin A level in patients with type 1 diabetes: A systematic review and meta-analysis.
Systematic review and meta-analysis of 8 case-control studies involving 689 participants to investigate serum vitamin A levels in type 1 diabetes mellitus patients. The analysis found a significant decrease in serum vitamin A levels in T1DM patients compared to controls.
Barriers and facilitators to the implementation of vitamin A supplementation programs in Africa: A systematic review.
This systematic review identifies barriers and facilitators to vitamin A supplementation programs in Africa, using the CFIR framework. It highlights issues like capsule stock-outs and limited resources as barriers, and Child Health Days and community health workers as facilitators, offering insights for improving VAS coverage.
Gut microbiota, vitamin A deficiency and autism spectrum disorder: an interconnected trio - a systematic review.
Systematic review investigating the connections among autism, gut microbiota alterations, and vitamin A deficiency. The review found significant alterations in the gut microbiota of individuals with autism and suggests vitamin A deficiency might play a role in autism onset. Vitamin A supplementation is highlighted as a potential therapeutic avenue for alleviating autism symptoms.
Prevalence of ocular manifestations of vitamin A deficiency in children: A systematic review.
Systematic review identifying the prevalence of ocular manifestations due to vitamin A deficiency in children. The review included 79 studies from 1972 to 2020, primarily from Asia and Africa, reporting xerophthalmia and night blindness as common manifestations.
The Relationship of Vitamin A and Neonatal Respiratory Diseases: A Meta-Analysis.
Meta-analysis of 24 articles examining the relationship between vitamin A and neonatal respiratory diseases. Vitamin A deficiency was associated with adverse outcomes in neonatal respiratory diseases, while supplementation was found to be an effective therapeutic measure.
Vitamin A deficiency among pregnant women in Ethiopia: a systematic review and meta-analysis.
Systematic review and meta-analysis of 15 studies involving 37,618 pregnant women in Ethiopia, finding a 29% prevalence of vitamin A deficiency. Socio-economic and sociodemographic factors were identified as affecting vitamin A deficiencies.
Comparative efficacy of oral drugs for chronic radiation proctitis - a systematic review.
Systematic review and meta-analysis of oral treatments for chronic radiation proctitis (CRP) including 10 RCTs and 1 retrospective study with 898 participants. Oral TCM drinks, retinyl palmitate, and a high-fiber diet showed significant improvement in CRP symptoms, while oral pentoxifylline and tocopherol did not show significant effects.
Natural history of retinitis pigmentosa based on genotype, vitamin A/E supplementation, and an electroretinogram biomarker.
A randomized clinical trial from 1984 to 1992 investigated the effects of vitamin A and vitamin E supplementation on retinitis pigmentosa (RP) progression. Vitamin A's beneficial effect was not detectable in the cohort as a whole, while vitamin E had a deleterious effect. Genetic subtype and electroretinogram implicit time were significant predictors of RP progression.
Vitamin A Nutritional Status and Clinical Outcomes in COVID-19: A Systematic Review.
Systematic review assessing the relationship between vitamin A nutritional status and clinical outcomes in COVID-19 patients. Seven observational studies were included, with some showing borderline or deficient retinol levels associated with worsened clinical outcomes, suggesting a possible association between retinol and COVID-19 outcomes.
Efficacy of different nutrients in age-related macular degeneration: A systematic review and network meta-analysis.
Systematic review and network meta-analysis of 13 studies with 85321 individuals assessing the efficacy of antioxidants on age-related macular degeneration (AMD). Carotenoids and zinc showed better improvement in visual acuity, while carotenoids (β-carotene) were most effective in delaying AMD progression. Multivitamin supplementation did not prevent late AMD development.
Prevalence of vitamin A deficiency in women of childbearing age in Brazil: a systematic review and meta-analysis.
Systematic review and meta-analysis assessing the prevalence of vitamin A deficiency in Brazilian women of childbearing age. The study included 32 studies with 12,577 women, finding a deficiency prevalence of 13%, higher in pregnant women, and increasing over the decades.
Vitamin A Concentration in Human Milk: A Meta-Analysis.
Meta-analysis of 76 studies involving 9171 samples to assess vitamin A concentration in human milk throughout lactation. Results showed a significant decrease in vitamin A concentration as lactation progressed, with specific concentrations reported for colostrum, transitional, early mature, and late mature stages. No significant differences were found between Chinese and non-Chinese samples.
Association of vitamin A and its organic compounds with stroke - a systematic review and meta-analysis.
Systematic review and meta-analysis evaluating the association between vitamin A, its organic compounds, and stroke risk and mortality. The pooled effect showed an inverse association, with retinol and beta-carotene being the most effective compounds in reducing stroke risk and mortality.
Vitamin A in children's pneumonia for a COVID-19 perspective: A systematic review and meta-analysis of 15 trials.
Systematic review and meta-analysis of 15 RCTs involving 3496 children with pneumonia, assessing vitamin A as an adjuvant therapy. Vitamin A combined with conventional therapy improved clinical efficacy, shortened the duration of symptoms, and hospitalization, but did not reduce mortality.
Oral vitamin A supplementation in preterm infants to improve health outcomes: A systematic review and meta-analysis.
Systematic review and meta-analysis of RCTs evaluating oral vitamin A supplementation in preterm infants. The study found no significant effect on mechanical ventilation duration, oxygen requirement at 36 weeks PMA, or moderate-to-severe BPD at 36 weeks PMA. However, a slight reduction in noninvasive ventilation duration was observed without adverse drug-related events.
Enteral Low-Dose Vitamin A Supplementation in Preterm or Low Birth Weight Infants to Prevent Morbidity and Mortality: a Systematic Review and Meta-analysis.
Systematic review and meta-analysis of enteral low-dose vitamin A supplementation in preterm or low birth weight infants. The study found increased serum retinol levels but little or no effect on mortality, sepsis, bronchopulmonary dysplasia, retinopathy of prematurity, or duration of hospitalization.
Influence of Vitamin A supplementation on inflammatory biomarkers in adults: a systematic review and meta-analysis of randomized clinical trials.
This systematic review and meta-analysis evaluated the effects of vitamin A supplementation on inflammatory biomarkers in adults. The analysis found that vitamin A supplementation significantly increased CRP concentrations, while it decreased TNF-α concentrations in chronic hepatitis B conditions. There was also an inverse association between vitamin A supplementation and IL-6 concentrations in various infection conditions.
Excessive Vitamin A Supplementation Increased the Incidence of Acute Respiratory Tract Infections: A Systematic Review and Meta-Analysis.
Systematic review and meta-analysis of 26 randomized trials involving 50,944 participants assessing the effects of vitamin A supplementation on acute respiratory tract infections in children. No significant association was found with the incidence of infections compared to placebo, but excessive supplementation increased the incidence in well-nourished children.
Biofortified and fortified maize consumption reduces prevalence of low milk retinol, but does not increase vitamin A stores of breastfeeding Zambian infants with adequate reserves: a randomized controlled trial.
RCT of 255 lactating women and their infants in Zambia, testing biofortified and fortified maize consumption. Both interventions improved milk retinol concentration but did not increase infant total body stores of vitamin A, likely due to adequate baseline levels.
Impact of Maternal Daily Oral Low-Dose Vitamin A Supplementation on the Mother-Infant Pair: A Randomised Placebo-Controlled Trial in China.
RCT in China evaluating daily oral low-dose vitamin A supplementation on lactating mothers and their infants. Maternal serum retinol concentrations increased in the supplementation group, while breast milk retinol concentrations decreased less than in the control group. No effect on infant health status was observed.
Vitamin A and Bone Fractures: Systematic Review and Meta-Analysis.
Systematic review and meta-analysis examining the association between vitamin A and fracture risk. High dietary intake of total vitamin A or retinol increased hip fracture risk, while high intake of some carotenoids reduced hip fracture risk. Total fracture risk was not associated with any vitamin A compound.
Which blood cutoff value should be used for vitamin A deficiency in children aged 3-10 years? A systematic review.
Systematic review and meta-analysis to identify blood retinol concentrations for determining severe vitamin A deficiency in children aged 3-10 years. The study found that blood retinol concentrations have low diagnostic accuracy for severe vitamin A deficiency in this age group, with unclear evidence about the preferable cutoff point.
Systematic Review and Meta-Analysis of the Relative Dose-Response Tests to Assess Vitamin A Status.
Systematic review and meta-analysis of the relative dose-response (RDR) and modified-RDR (MRDR) tests to assess vitamin A status. The review summarizes the sensitivity and specificity of these tests and their response to vitamin A intake in deficient populations. It also examines the impact of various physiological and pathological states on the tests.
Effectiveness of Interventions for Managing Acute Malnutrition in Children under Five Years of Age in Low-Income and Middle-Income Countries: A Systematic Review and Meta-Analysis.
Systematic review and meta-analysis of 42 studies on interventions for managing acute malnutrition in children under five in low- and middle-income countries. The review evaluates the effectiveness of RUTF, RUSF, prophylactic antibiotics, and vitamin A supplementation. Findings suggest mixed results for vitamin A supplementation on weight gain and mortality among children with SAM.
Prevalence of Vitamin A Deficiency among Preschool Children in Ethiopia: A Systematic Review and Meta-Analysis.
Systematic review and meta-analysis assessing the prevalence of vitamin A deficiency among preschool children in Ethiopia. The study found that both clinical and subclinical vitamin A deficiencies remain a public health problem, with a decrease in night blindness and Bitot's spot prevalence over time, but subclinical deficiency rates remain high.
Systematic review and meta-analysis approach on vitamin A fortified foods and its effect on retinol concentration in under 10 year children.
Systematic review and meta-analysis of trials assessing the effect of vitamin A fortified foods on serum vitamin A concentration in children under 10 years. The pooled effect size showed that vitamin A fortification increased retinol concentration, suggesting a reduction in vitamin A deficiency.
Early neonatal vitamin A supplementation and infant mortality: an individual participant data meta-analysis of randomised controlled trials.
Meta-analysis of 11 randomised placebo-controlled trials with 163,567 children assessing neonatal vitamin A supplementation (NVAS) on infant mortality. NVAS reduced 6-month mortality in Southern Asia and in contexts with moderate or severe vitamin A deficiency, but had no beneficial effect in Africa where vitamin A deficiency and early infant mortality are lower.
[Effect of vitamin A as an adjuvant therapy for pneumonia in children: a Meta analysis].
Meta-analysis of 15 RCTs with 3,021 children with pneumonia assessing vitamin A as an adjuvant therapy. Vitamin A supplementation did not reduce mortality but increased clinical response rate and shortened duration of symptoms and hospital stay without increasing adverse reactions.
Vitamin A supplementation for preventing morbidity and mortality in children from six months to five years of age.
Meta-analysis of 47 studies involving approximately 1,223,856 children assessing the effects of vitamin A supplementation on morbidity and mortality. Vitamin A supplementation was associated with a 12% reduction in all-cause mortality and reduced incidence of diarrhoea and measles, though it increased the risk of vomiting within the first 48 hours.
Mortality Benefits of Vitamin A Are Not Affected by Varying Frequency, Total Dose, or Duration of Supplementation.
Meta-analysis of 17 randomized controlled trials involving 1,180,718 children under 5 years old, assessing the impact of vitamin A supplementation on mortality. Vitamin A reduced mortality by 22%, with no modification of effect by dosing frequency, total dose, or duration of supplementation.
The Effect of Vitamin A on Fracture Risk: A Meta-Analysis of Cohort Studies.
This meta-analysis evaluated the influence of dietary intake and blood level of vitamin A (total vitamin A, retinol, or β-carotene) on total and hip fracture risk. Higher dietary intake of retinol and total vitamin A may slightly decrease total fracture risk but increase hip fracture risk. Lower blood level of retinol may slightly increase total and hip fracture risk. Higher β-carotene intake was weakly associated with increased total fracture risk.
Neonatal vitamin A supplementation for the prevention of mortality and morbidity in term neonates in low and middle income countries.
Meta-analysis of 12 trials involving 168,460 neonates to evaluate the effect of vitamin A supplementation on mortality and morbidity in term neonates in low and middle income countries. The analysis found no statistically significant effect on infant mortality at six or 12 months of age in the vitamin A group compared to the control group.
Vitamin A supplements for reducing mother-to-child HIV transmission.
Meta-analysis of five trials assessing vitamin A supplementation in HIV-positive women during pregnancy and postpartum. The supplementation likely has little or no effect on mother-to-child HIV transmission but may increase birthweight and reduce low birthweight incidence.
Vitamin A supplementation for postpartum women.
Meta-analysis of 14 trials with 25,758 women and infant pairs evaluating vitamin A supplementation for postpartum women. No evidence of benefit on maternal and infant mortality and morbidity was found, although maternal breast milk retinol concentrations improved with supplementation.
Vitamin A supplementation during pregnancy for maternal and newborn outcomes.
Meta-analysis of 19 trials with over 310,000 women evaluating vitamin A supplementation during pregnancy. Vitamin A supplementation does not affect maternal or perinatal mortality but reduces maternal night blindness, anaemia, and infection in areas with vitamin A deficiency or among HIV-positive women.
Association of Dietary Vitamin A and β-Carotene Intake with the Risk of Lung Cancer: A Meta-Analysis of 19 Publications.
Meta-analysis of 19 studies with 10,261 lung cancer cases assessing the association between dietary vitamin A and β-carotene intake and lung cancer risk. Higher intake of both was associated with reduced lung cancer risk, particularly in Asian and American populations.
The relationship between vitamin A and risk of fracture: meta-analysis of prospective studies.
Meta-analysis of prospective studies assessing the effects of vitamin A, retinol, and beta-carotene on fracture risk. High intake of vitamin A and retinol increased hip fracture risk, while beta-carotene did not. Both high and low blood retinol levels increased hip fracture risk, showing a U-shaped relationship. Total fracture risk was not significantly affected by vitamin A or retinol levels.
Effects of vitamin A and β-carotene supplementation on birth size and length of gestation in rural Bangladesh: a cluster-randomized trial.
Cluster-randomized, placebo-controlled trial in rural Bangladesh examining the effects of weekly antenatal vitamin A and β-carotene supplementation on birth weight, length, circumferential body measures, and length of gestation. The study found no differences in birth outcomes between supplementation and placebo groups.
Vitamin A supplements for preventing mortality, illness, and blindness in children aged under 5: systematic review and meta-analysis.
Systematic review and meta-analysis of 43 trials with about 215,633 children aged 6 months to 5 years. Vitamin A supplementation was associated with a 24% reduction in all-cause mortality, reduced incidence of diarrhoea and measles, and reduced prevalence of vision problems including night blindness and xerophthalmia. An increased risk of vomiting was reported within the first 48 hours of supplementation.
Neonatal vitamin A supplementation for the prevention of mortality and morbidity in term neonates in developing countries.
Meta-analysis of seven trials involving 51,446 neonates in developing countries to evaluate the effect of vitamin A supplementation on mortality and morbidity. The analysis showed a statistically significant reduction in infant mortality at six months in the vitamin A group compared to control, but no significant effect at 12 months. The findings suggest a potential beneficial effect of neonatal vitamin A supplementation on early infant mortality.
Vitamin A and risk of cervical cancer: a meta-analysis.
This meta-analysis evaluated the association of vitamin A intake and blood levels with cervical cancer risk, including 11 articles on dietary vitamin A and 4 on blood vitamin A, totaling 12,136 participants. The analysis found that both vitamin A intake and blood levels were inversely associated with cervical cancer risk.
Vitamin A supplementation for reducing the risk of mother-to-child transmission of HIV infection.
Meta-analysis of five RCTs involving 7,528 HIV-infected women in sub-Saharan Africa assessing the effect of vitamin A supplementation on mother-to-child transmission of HIV. The study found no evidence that vitamin A supplementation affects the risk of MTCT of HIV, but it significantly improved birth weight.
Maternal vitamin A and β-carotene supplementation and risk of bacterial vaginosis: a randomized controlled trial in rural Bangladesh.
Cluster-randomized, placebo-controlled trial in rural Bangladesh assessing the effect of weekly vitamin A or β-carotene supplementation on bacterial vaginosis (BV) risk during pregnancy and postpartum. Vitamin A supplementation reduced the prevalence and incidence of BV at 3 months postpartum compared to placebo.
Vitamin A supplementation to prevent mortality and short- and long-term morbidity in very low birthweight infants.
Meta-analysis of nine trials evaluating vitamin A supplementation in very low birthweight infants. Vitamin A supplementation reduced death or oxygen requirement at one month and at 36 weeks' postmenstrual age. No differences in neurodevelopmental outcomes were observed at 18 to 22 months of age.
Routine vitamin A supplementation for the prevention of blindness due to measles infection in children.
Meta-analysis of two RCTs involving 260 children with measles comparing vitamin A supplementation to placebo. The studies did not report blindness or ocular morbidities as endpoints. One trial showed a significant increase in serum retinol levels in the vitamin A group one week after supplementation, but not at six weeks. No significant differences in weight gain were observed.
Vitamin A and retinoid derivatives for lung cancer: a systematic review and meta analysis.
Systematic review and meta-analysis of 248 studies on vitamin A and retinoids for lung cancer treatment and prevention. Insufficient evidence supports their use, with some studies showing benefits and others indicating increased risk, particularly in smokers. Bexarotene showed promise in increasing survival in a subset of patients.
Vitamin A supplementation for the prevention of morbidity and mortality in infants six months of age or less.
Meta-analysis evaluating the effect of vitamin A supplementation in postpartum mothers and infants under six months in low and middle income countries. The study found no convincing evidence that vitamin A supplementation reduces infant mortality or morbidity, but noted an increased risk of bulging fontanelle in infants.
Vitamin A supplementation for preventing morbidity and mortality in children from 6 months to 5 years of age.
Meta-analysis of 43 trials involving 215,633 children aged 6 months to 5 years, evaluating the effect of vitamin A supplementation on morbidity and mortality. Vitamin A supplementation reduced all-cause mortality by 24% and diarrhoea mortality by 28%, but had no significant effect on mortality from measles, respiratory disease, or meningitis. It reduced the incidence of diarrhoea and measles morbidity, but increased the risk of vomiting within the first 48 hours.
Vitamin A supplementation for postpartum women.
Meta-analysis of 12 trials with 25,465 mother-baby pairs assessing postpartum maternal vitamin A supplementation. No significant impact on maternal or infant mortality and morbidity, except for fewer episodes of fever in one small trial. Vitamin A enhanced serum and breast milk retinol at three months, but improvements were not sustained.
Vitamin A supplementation and BCG vaccination at birth in low birthweight neonates: two by two factorial randomised controlled trial.
RCT in Bissau, Guinea-Bissau, with 1717 low birthweight neonates to assess the effect of vitamin A supplementation and BCG vaccination at birth on mortality. Vitamin A supplementation showed no significant overall effect on mortality, but a significant sex interaction was observed, with potential harm in girls.
Prevention of diarrhoea in children with HIV infection or exposure to maternal HIV infection.
Systematic review of RCTs and nonrandomised studies examining vitamin A, zinc, and cotrimoxazole for preventing diarrhoea in HIV-infected and -exposed children. Vitamin A reduced overall mortality in HIV-infected children. Zinc reduced physician visits for watery diarrhoea in one trial. Cotrimoxazole reduced mortality and hospitalisations.
Vitamin A for non-measles pneumonia in children.
Meta-analysis of five trials involving 1453 infants and children with non-measles pneumonia treated with adjunctive vitamin A. No significant reduction in mortality or hospital stay duration was found. Vitamin A was associated with a reduction in antibiotic firstline failure and recurrent bronchopneumonia, but disease severity was worse with high-dose vitamin A.
Vitamin A for acute respiratory infection in developing countries: a meta-analysis.
Meta-analysis of five double-blinded, randomized, controlled intervention studies with 2177 children to assess high-dose vitamin A's effect on acute lower respiratory tract infection. No significant differences were found in recovery measures or mortality between the vitamin A and placebo groups.
Effect of vitamin A supplementation on childhood morbidity and mortality.
Double-blind RCT of 1520 children in Chandigarh slums, randomized to vitamin A or placebo. Vitamin A supplementation significantly reduced vitamin A deficiency, incidence of diarrhoea and measles, and risk of death, but not acute respiratory infections.
Vitamin A or beta-carotene supplementation reduces symptoms of illness in pregnant and lactating Nepali women.
Cluster-randomized trial of 15,832 Nepali women assessing weekly vitamin A and beta-carotene supplementation on pregnancy and postpartum illness symptoms. Vitamin A reduced symptoms of nausea, faintness, night blindness, and shortened labor duration in late pregnancy. Both supplements reduced postpartum symptoms of loose stools and night blindness, with beta-carotene also reducing high fever symptoms.
Screening of Influencing Factors of Dry Eye Disease and the Exploration of New Diagnosis and Treatment Model Based on Community Health Management Combined with Tertiary Hospitals.
The study screened influencing factors of dry eye disease and evaluated a new diagnosis and treatment model combining tertiary hospitals with community health management. Vitamin A deficiency was identified as an influencing factor. The management group showed better disease cognition, improved tear film break-up time and Schirmer I test results, and lower OSDI scores compared to the control group.
Therapeutic effects of olfactory training and systemic vitamin A in patients with COVID-19-related olfactory dysfunction: a double-blinded randomized controlled clinical trial.
This double-blinded randomized controlled trial evaluated the therapeutic effect of olfactory training with and without oral vitamin A for COVID-19-related olfactory dysfunction in 90 patients. The study found that olfactory training significantly improved smell alteration, but adding daily oral vitamin A did not lead to better results.
A randomized phase 2 trial of oral vitamin A for graft-versus-host disease in children and young adults.
A randomized phase 2 trial of oral vitamin A in 80 recipients of hematopoietic stem cell transplantation (HSCT) to assess its effect on graft-versus-host disease (GVHD). The incidence of acute GVHD was lower in the vitamin A arm compared to placebo, with significant reductions in acute gastrointestinal GVHD and chronic GVHD. Vitamin A was associated with lower levels of inflammatory markers and a more favorable gut microbiome.
Interventions to prevent mother-to-child transmission in breastfeeding mothers with HIV: a systematic review and meta-analysis of randomized controlled trials.
Systematic review and meta-analysis of interventions to prevent mother-to-child transmission of HIV during breastfeeding. Seven studies were identified, with four focusing on antiretroviral therapy (ART) and one on high-dose vitamin A. ART significantly reduced postnatal HIV transmission risk, but the effectiveness of high-dose vitamin A remains unclear.
The Impact of Vitamin A Deficiency on Tuberculosis Progression.
Longitudinal cohort study nested within an RCT among HIV-infected patients in Haiti, examining the impact of vitamin A deficiency on TB progression. Vitamin A deficiency was associated with a higher likelihood of developing TB. Animal studies showed that vitamin A deficiency led to more severe TB pathology, which was mitigated by reintroducing vitamin A.
Evaluation and comparison of vitamin A supplementation with standard therapies in the treatment of patients with COVID-19.
Triple-blind controlled trial comparing vitamin A supplementation with standard COVID-19 treatment in 182 outpatients. The vitamin A group showed significantly greater decreases in clinical symptoms such as fever, body ache, weakness, and fatigue, as well as paraclinical symptoms, compared to the standard treatment alone.
Supplementation With Carotenoids, Omega-3 Fatty Acids, and Vitamin E Has a Positive Effect on the Symptoms and Progression of Alzheimer’s Disease
RCT of 77 patients with mild-moderate Alzheimer's disease comparing daily supplementation of fish oil, carotenoids, and vitamin E to placebo for 12 months. The active group showed significant improvements in blood and skin carotenoid levels, omega-3 fatty acids, and vitamin E concentrations, as well as better performance in memory and mood measures.
Vitamin A-fortified rice increases total body vitamin A stores in lactating Thai women measured by retinol isotope dilution: a double-blind, randomized, controlled trial.
A double-blind, randomized controlled trial assessed the efficacy of vitamin A-fortified rice on total body vitamin A stores in 70 lactating Thai women. The intervention group showed a significant increase in total body vitamin A stores compared to the control group, indicating improved vitamin A status.
Assessment of a combined strategy of seasonal malaria chemoprevention and supplementation with vitamin A, zinc and Plumpy'Doz™ to prevent malaria and malnutrition in children under 5 years old in Burkina Faso: a randomized open-label trial (SMC-NUT).
Randomized open-label trial assessing the combined strategy of seasonal malaria chemoprevention and supplementation with vitamin A, zinc, and Plumpy'Doz to prevent malaria and malnutrition in children under 5 years old in Burkina Faso. The primary outcome is the incidence of malaria, with secondary outcomes including anthropometric indicators and prevalence of molecular markers of antimalarial resistance.
Enteral Vitamin A for Reducing Severity of Bronchopulmonary Dysplasia: A Randomized Trial.
RCT comparing enteral water-soluble vitamin A supplementation to placebo in extremely preterm infants to reduce the severity of bronchopulmonary dysplasia (BPD). Vitamin A improved plasma retinol levels but did not reduce the severity of BPD.
Efect of vitamin A suplementation: a systematic review.
Systematic review evaluating the effect of vitamin A supplementation in postpartum women and infants on serum retinol levels and breast milk. Supplementation increased serum retinol and breast milk concentrations in the short term, particularly when maternal levels were initially low. No significant change was observed when maternal serum concentrations were adequate.
A systematic review and meta-analysis of the association between vitamin A intake, serum vitamin A, and risk of liver cancer.
This systematic review and meta-analysis examined the association between vitamin A intake, serum vitamin A, and liver cancer risk in adults. The meta-analysis of five studies showed no association between serum retinol and liver cancer. The systematic review found no association between intake and serum levels of α-carotene, β-cryptoxanthin, and liver cancer risk. Associations with retinol and β-carotene intake were inconclusive.
Effect of vitamin A supplementation on iron status in humans: A systematic review and meta-analysis.
Systematic review and meta-analysis assessing the effect of vitamin A supplementation on iron status and anemia in humans. The analysis of 23 studies found that vitamin A supplementation reduces the risk of anemia by 26% and raises hemoglobin levels, with significant increases in serum ferritin levels in pregnant and lactating women.
A systematic review and meta-analysis of randomized controlled trials to evaluating the trend of cytokines to vitamin A supplementation in autoimmune diseases.
Systematic review and meta-analysis of RCTs evaluating the effect of vitamin A on cytokine gene expression in autoimmune diseases. Vitamin A supplementation significantly altered gene expression of inflammatory and anti-inflammatory cytokines, suggesting potential effects on autoimmune disease symptoms.
Retinol-to-Fat Ratio and Retinol Concentration in Human Milk Show Similar Time Trends and Associations with Maternal Factors at the Population Level: A Systematic Review and Meta-Analysis.
Systematic review and meta-analysis of studies measuring retinol-to-fat ratio and retinol concentration in human milk. Retinol levels were highest in colostrum, declined in early lactation, and stabilized by 2-4 weeks. Retinol concentration was positively correlated with milk fat and maternal vitamin A intake, with postpartum vitamin A supplementation increasing breast-milk retinol levels.
Impact of Vitamin A Supplementation on Pregnant Women and on Women Who Have Just Given Birth: A Systematic Review.
Systematic review evaluating the impact of vitamin A supplementation on pregnant women and women who have just given birth. Supplementation increased liver stores of vitamin A, improved immune system function, and reduced gestational night blindness, but did not affect childbirth outcomes or mortality. Additional lung function improvements were noted in preschool-aged children.
The Prevalence of Vitamin A Deficiency in Chinese Children: A Systematic Review and Bayesian Meta-Analysis.
Systematic review and Bayesian meta-analysis of vitamin A deficiency (VAD) in Chinese children, analyzing 54 studies. The prevalence of VAD and marginal VAD (MVAD) decreased with age, with higher rates in rural areas. In 2015, VAD prevalence was 5.16% and MVAD was 24.29% among children aged 12 and under.
Double-blind cluster randomised controlled trial of wheat flour chapatti fortified with micronutrients on the status of vitamin A and iron in school-aged children in rural Bangladesh.
A double-blind cluster RCT in rural Bangladesh evaluated the impact of micronutrient-fortified wheat flour chapatti on vitamin A and iron status in school-aged children. The fortified chapatti significantly increased serum retinol concentration and reduced vitamin A deficiency, but showed no effect on iron status, haemoglobin levels, or anaemia.
Inflammation and Vitamin A.
The study investigates the relationship between low serum retinol concentrations and inflammation, despite no evidence of vitamin A deficiency. It categorizes participants into groups based on acute-phase protein levels and uses meta-analysis to calculate correction factors to adjust retinol concentrations for inflammation.
Association of vitamin A and β-carotene with risk for age-related cataract: a meta-analysis.
Meta-analysis of 22 articles examining the association of vitamin A and β-carotene with cataract risk. Higher intakes of vitamin A and β-carotene were inversely associated with cataract risk, suggesting a protective effect.
Association between vitamin A, retinol intake and blood retinol level and gastric cancer risk: A meta-analysis.
Meta-analysis of 31 studies assessing the association between vitamin A, retinol intake, and blood retinol level with gastric cancer risk. Vitamin A intake significantly reduced gastric cancer risk, while retinol intake and blood retinol level showed a marginally inverse association.
A Systematic Review of Nutritional Supplementation in HIV-Infected Children in Resource-Limited Settings.
Systematic review of nutritional supplementation in HIV-infected children in resource-limited settings. Vitamin A supplementation was associated with reduced mortality, while macronutrient supplementation improved anthropometrics. Multiple-micronutrient supplementation did not improve measured health outcomes.
[Effects of vitamin A, vitamin A plus iron and multiple micronutrient-fortified seasoning powder on iron metabolic homeostasis].
This randomized controlled trial evaluated the effects of vitamin A, vitamin A plus iron, and a multiple micronutrient-fortified seasoning powder on iron metabolic homeostasis in 226 preschool children. The study found that vitamin A intervention significantly affected iron storage and mobilization, while the combination of vitamin A and other micronutrients improved iron deficiency.
Effect of vitamin A, vitamin A plus iron and multiple micronutrient-fortified seasoning powder on infectious morbidity of preschool children.
RCT of 226 preschool children in Chongqing, China, comparing diets fortified with vitamin A, vitamin A plus iron, and multiple micronutrients over 6 months. Group III, fortified with multiple micronutrients, showed a lower incidence of respiratory and diarrhea-related illnesses compared to groups I and II.
Vitamin A supplementation during pregnancy for maternal and newborn outcomes.
Meta-analysis of 16 trials evaluating vitamin A supplementation during pregnancy on maternal and newborn outcomes. Vitamin A supplementation does not significantly affect maternal or perinatal mortality but reduces maternal night blindness, anaemia, and clinical infection in vitamin A deficient populations and HIV-positive women.
Effectiveness of measles vaccination and vitamin A treatment.
Systematic review and meta-analysis of RCTs and quasi-experimental studies assessing the effectiveness of measles vaccine and vitamin A treatment. The meta-analysis found that vitamin A treatment with at least two doses reduced measles mortality by 62%.
Vitamin A for preventing acute lower respiratory tract infections in children up to seven years of age.
Meta-analysis assessing the effectiveness and safety of vitamin A for preventing acute lower respiratory tract infections (LRTIs) in children up to seven years of age. Most studies found no significant effect, with some reporting increased incidence of LRTIs and symptoms in normal children, but a reduction in children with poor nutritional status.
Randomized controlled safety and efficacy trial of 2 vitamin A supplementation schedules in Tanzanian infants.
RCT in Tanzanian infants and their mothers to evaluate the safety and efficacy of vitamin A supplementation at the same time as routine vaccination. High-dose vitamin A was well tolerated but did not significantly reduce morbidity or enhance vitamin A status at 6 months.
Effect of vitamin A supplementation with BCG vaccine at birth on vitamin A status at 6 wk and 4 mo of age.
RCT studying the effect of 50,000 IU vitamin A supplementation with BCG vaccine at birth on vitamin A status in children. VAS did not improve vitamin A status overall but showed a temporary improvement in children of noneducated mothers. Subsequent DTP vaccines negatively affected vitamin A status in recipients.
Vitamin A supplementation to prevent mortality and short and long-term morbidity in very low birthweight infants.
Meta-analysis of eight trials assessing vitamin A supplementation in very low birthweight infants. Supplementation was associated with a reduction in death or oxygen requirement at one month of age and oxygen requirement among survivors at 36 weeks postmenstrual age. No differences in neurodevelopmental outcomes were observed at 18 to 22 months corrected age.
Effects of moderate doses of vitamin A as an adjunct to the treatment of pneumonia in underweight and normal-weight children: a randomized, double-blind, placebo-controlled trial.
RCT evaluating the effect of moderate doses of vitamin A as an adjunct to standard antimicrobial treatment on pneumonia in children. No overall differences were observed in the duration of pneumonia signs between the vitamin A and placebo groups, but a beneficial effect was noted in children with high basal serum retinol concentrations.
Vitamin A for treating measles in children.
Meta-analysis of randomized controlled trials assessing vitamin A therapy in children with measles. Two doses of vitamin A were associated with reduced mortality and pneumonia-specific mortality in children under two years, but no overall significant reduction in mortality was found.
Effects of subclinical infection on plasma retinol concentrations and assessment of prevalence of vitamin A deficiency: meta-analysis.
Meta-analysis of 15 studies assessing the impact of subclinical infection on plasma retinol concentrations to estimate vitamin A deficiency more accurately. Findings show that retinol values are higher in individuals with normal acute-phase protein concentrations compared to those with raised concentrations. The study recommends including measurements of serum C-reactive protein and alpha1-acid-glycoprotein in surveys to estimate vitamin A deficiency.