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Food and Nutrition Bulletin Jun 2015In recent decades, the general socioeconomic situation in Latin America and the Caribbean countries has improved, and many vitamin A programs have been implemented in an... (Review)
Review
BACKGROUND
In recent decades, the general socioeconomic situation in Latin America and the Caribbean countries has improved, and many vitamin A programs have been implemented in an attempt to reduce vitamin A deficiency in the region.
OBJECTIVE
To examine vitamin A status in Latin America and the Caribbean based on serum retinol concentrations and to contrast available data published before and after 1998.
METHODS
A systematic review was performed. National surveys or representative studies that reported vitamin A status were selected.
RESULTS
Ten national surveys and six representative studies were identified. Data for children under 6 years of age indicate that Guatemala and Nicaragua have practically eradicated vitamin A deficiency (less than 2% prevalence of serum retinol < 20 μg/dL). In Costa Rica, Cuba, El Salvador, and Panama, the prevalence of vitamin A deficiency ranged from 2.8% to 9.4%. In Peru, Honduras, Argentina, Ecuador, and Brazil, vitamin A deficiency is a moderate public health problem (prevalence from 14.0% to 17.4%), while in Colombia, Mexico, and Haiti it is a severe public health problem (prevalence from 24.3% to 32.0%). Disadvantaged groups (indigenous people and those of Afro-Colombian descent) have the highest rates of deficiency. The prevalence of vitamin A deficiency is under 20% in school-children and adult women. When data published before and after 1998 for children under 6 years of age were compared, most Central American countries had a reduction in the prevalence of vitamin A deficiency (p < .05), whereas in South American countries, the prevalence of vitamin A deficiency increased over time (p < .05).
CONCLUSIONS
The prevalence of vitamin A deficiency in children under 6 years of age has decreased in many Central American countries, but vitamin A deficiency still remains a public health problem in numerous Latin America and Caribbean countries, especially among disadvantaged and vulnerable groups. Because of issues with the accuracy of the serum retinol biomarker reflecting body stores, these results must be interpreted with caution.
Topics: Adult; Argentina; Brazil; Caribbean Region; Central America; Child; Child, Preschool; Colombia; Ecuador; Female; Guatemala; Haiti; Humans; Infant; Latin America; Mexico; Nicaragua; Nutritional Status; Panama; Peru; Vitamin A; Vitamin A Deficiency
PubMed: 26125200
DOI: 10.1177/0379572115585743 -
International Journal of Molecular... Oct 2023Bisphenols such as bisphenol A (BPA), S (BPS), C (BPC), F (BPF), AF (BPAF), tetrabromobisphenol, nonylphenol, and octylphenol are plasticizers used worldwide to... (Meta-Analysis)
Meta-Analysis Review
Bisphenols such as bisphenol A (BPA), S (BPS), C (BPC), F (BPF), AF (BPAF), tetrabromobisphenol, nonylphenol, and octylphenol are plasticizers used worldwide to manufacture daily-use articles. Exposure to these compounds is related to many pathologies of public health importance, such as infertility. Using a protector compound against the reproductive toxicological effects of bisphenols is of scientific interest. Melatonin and vitamins have been tested, but the results are not conclusive. To this end, this systematic review and meta-analysis compared the response of reproductive variables to melatonin and vitamin administration as protectors against damage caused by bisphenols. We search for controlled studies of male rats exposed to bisphenols to induce alterations in reproduction, with at least one intervention group receiving melatonin or vitamins (B, C, or E). Also, molecular docking simulations were performed between the androgen (AR) and estrogen receptors (ER), melatonin, and vitamins. About 1234 records were initially found; finally, 13 studies were qualified for review and meta-analysis. Melatonin plus bisphenol improves sperm concentration and viability of sperm and increases testosterone serum levels compared with control groups; however, groups receiving vitamins plus bisphenols had lower sperm concentration, total testis weight, and testosterone serum levels than the control. In the docking analysis, vitamin E had the highest negative MolDock score, representing the best binding affinity with AR and ER, compared with other vitamins and melatonin in the docking. Our findings suggest that vitamins could act as an endocrine disruptor, and melatonin is most effective in protecting against the toxic effects of bisphenols.
Topics: Male; Rats; Animals; Melatonin; Vitamins; Molecular Docking Simulation; Semen; Benzhydryl Compounds; Reproduction; Receptors, Estrogen; Vitamin A; Vitamin K; Testosterone; Endocrine Disruptors
PubMed: 37834378
DOI: 10.3390/ijms241914930 -
Gynecologic Oncology Feb 2012To conduct a systematic review with meta-analysis of studies assessing the association of vitamin A (retinol, carotene and other carotenoids) intake or blood (serum or... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To conduct a systematic review with meta-analysis of studies assessing the association of vitamin A (retinol, carotene and other carotenoids) intake or blood (serum or plasma) levels of vitamin A (retinol and carotene) with risk of cervical cancer.
METHODS
We evaluated the studies published in English and Chinese on diet or blood vitamin A for the risk of cervical cancer. We also reviewed reference lists from retrieved articles. Meta-analysis was applied to calculate the combined effect values and their 95% confidence intervals. The risk of bias was assessed by the Egger regression asymmetry test.
RESULTS
As many as 11 articles on dietary vitamin A and 4 articles on blood vitamin A were selected according to the eligibility criteria and were included in the meta-analysis, for a total of 12,136 participants. The pooled odds ratios (ORs) of cervical cancer were 0.59 (95% CI, 0.49-0.72) for total vitamin A intake and 0.60 (95% CI, 0.41-0.89) for blood vitamin A levels. The combined ORs of cervical cancer were 0.80 (95% CI, 0.64-1.00), 0.51 (95% CI, 0.35-0.73) and 0.60 (95% CI, 0.43-0.84) for retinol, carotene and other carotenoid intake, and 1.14 (95% CI, 0.83-1.56) and 0.48 (95% CI, 0.30-0.77) for blood retinol and carotene.
CONCLUSIONS
Vitamin A intake and blood vitamin A levels were inversely associated with the risk of cervical cancer in this meta-analysis.
Topics: Female; Humans; Risk Factors; Uterine Cervical Neoplasms; Vitamin A
PubMed: 22005522
DOI: 10.1016/j.ygyno.2011.10.012 -
Advances in Nutrition (Bethesda, Md.) May 2018Vitamin A in human milk is critical for meeting infant requirements and building liver stores needed after weaning. A number of studies have measured milk retinol, but... (Meta-Analysis)
Meta-Analysis
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.
Vitamin A in human milk is critical for meeting infant requirements and building liver stores needed after weaning. A number of studies have measured milk retinol, but only a subset have corrected for fat, which serves as the retinol carrier in breast milk. The purpose of the present work was to review and analyze studies in which human-milk retinol concentrations were reported in relation to milk fat and to compare these results with unadjusted breast-milk retinol concentrations in terms of time trends over the course of lactation, influences of maternal nutritional and constitutional factors, and effects of maternal vitamin A supplementation. A systematic approach was used to search the available literature by using the US National Library of Medicine's MEDLINE/PubMed bibliographic search engine. Observational and intervention studies were included if the research was original and the retinol-to-fat ratio (retinol:fat) in human milk was measured at ≥1 time point during the first 12 mo of lactation. Retinol:fat and retinol were highest in colostrum, declined rapidly in early lactation, and achieved statistical stability by 2 and 4 wk lactation, respectively. In mature milk, retinol concentration was positively correlated with milk fat (r = 0.61, P = 0.008). Breast-milk retinol:fat and retinol were positively associated with maternal vitamin A intake but were associated with plasma retinol only when dietary intake was inadequate. Postpartum supplementation with high-dose vitamin A (200,000-400,000 IU) resulted in significantly higher breast-milk retinol:fat for 3 mo and retinol for 6 mo (P < 0.05). In populations, the 2 indexes show similar trends and associations with maternal factors. Future studies should monitor how the uptake of retinol into the mammary gland affects maternal vitamin reserves, particularly in women who are at risk of vitamin A deficiency.
Topics: Adult; Breast Feeding; Colostrum; Diet; Dietary Supplements; Female; Humans; Infant; Infant Nutritional Physiological Phenomena; Infant, Newborn; Lactation; Lipids; Maternal Nutritional Physiological Phenomena; Milk, Human; Nutritional Requirements; Nutritional Status; Postpartum Period; Vitamin A; Vitamin A Deficiency; Vitamins
PubMed: 29846525
DOI: 10.1093/advances/nmy021 -
Journal of Personalized Medicine Oct 2023Micronutrients are vital for general and oral health, and their potential anti-cancer properties are documented. We explore beneficial vitamins for oral potentially... (Review)
Review
BACKGROUND
Micronutrients are vital for general and oral health, and their potential anti-cancer properties are documented. We explore beneficial vitamins for oral potentially malignant disorders (OPMDs) and oral cancer (OC), assessing the therapeutic impacts of essential vitamin supplementation.
METHODS
We systematically review evidence on vitamin supplementation's therapeutic effects for OPMDs and OC. Relevant studies were identified through comprehensive searches of MEDLINE, Evidence-Based Medicine, and Web of Science until 16 May 2023. All studies underwent risk of bias using criteria modified from the Office of Health Assessment and Translation (OHAT) tool.
RESULTS
We analysed 80 papers. Vitamin K, studied in vitro, shows promising therapeutic potential. Vitamin C, investigated in vivo (animals and humans), demonstrated mixed animal results and generally positive human trial effects. Vitamin A's efficacy varied, with positive monotherapy or adjunct effects. Vitamins B and D showed therapeutic benefits. Oral cancer research was extensive, with a focus on oral lichen planus and oral leukoplakia among the 11 OPMDs. All bias levels were reported in 'selective reporting' and 'performance', except for "definitely high" in the 'selection', 'detection', and 'attrition/exclusion' domains.
CONCLUSIONS
Evidence of vitamin interventions for OPMDs and OC ranges from mixed to promising. Standardizing the study design and outcomes would enhance future research.
PubMed: 37888131
DOI: 10.3390/jpm13101520 -
Nutrients Dec 2023This systematic review aims to assess whether edible vegetable oils and fats fortified with vitamin A and/or D are effective and safe in improving vitamin intake and... (Meta-Analysis)
Meta-Analysis Review
Benefits and Harms of Edible Vegetable Oils and Fats Fortified with Vitamins A and D as a Public Health Intervention in the General Population: A Systematic Review of Interventions.
This systematic review aims to assess whether edible vegetable oils and fats fortified with vitamin A and/or D are effective and safe in improving vitamin intake and ameliorating deficiency states in the general population. In November 2022, we systematically searched MEDLINE, Cochrane CENTRAL, Scopus, Global Index Medicus, ClinicalTrials.gov, and WHO ICTRP (International Clinical Trials Registry Platform) for randomized controlled trials (RCT) and non-randomized studies of interventions (NRSI) investigating the fortification of edible vegetable oils and fats with either vitamin A or vitamin D or both as compared to the same vegetable oils and/or fats without vitamin A and D fortification or no interventions, in the general population, without age restriction. We assessed the methodological quality of included RCTs using Cochrane's risk of bias tool 2.0 and of NRSIs using ROBINS-I tool. We performed random-effects meta-analysis and assessed certainty of evidence using GRADE. We included eight studies. Available evidence showed no significant effect of fortification with vitamin A on serum retinol levels (RCTs: MD 0.35 µmol/L, 95% CI -0.43 to 1.12; two trials; 514 participants; low-certainty evidence; CCTs: MD 0.31 µmol/L, 95% CI -0.18 to 0.80; two trials; 205 participants; very low-certainty evidence) and on subclinical vitamin A deficiency. Low-certainty evidence showed no effect of vitamin D fortification on serum 25-hydroxy vitamin D concentration (MD 6.59 nmol/L, 95% CI -6.89 to 20.07; one trial; 62 participants). In conclusion, vitamin A-fortified vegetable oils and fats may result in little to no difference in serum retinol levels in general populations. The dose of vitamin A used in the trials may be safe but may not be sufficient to reduce subclinical vitamin A deficiency. Further, the evidence suggests that vitamin D fortification results in little to no difference in serum 25-hydroxy vitamin D concentration. Several aspects of providing fortified oils and fats to the general population as a public health intervention should be further investigated, including optimal fortification dose, effects on vitamin D deficiency and its clinical symptoms and potential adverse effects.
Topics: Humans; Vitamins; Vitamin A; Vitamin A Deficiency; Vegetables; Public Health; Plant Oils; Food, Fortified; Vitamin K; Vitamin D
PubMed: 38140394
DOI: 10.3390/nu15245135 -
Nutrients Jul 2023Nutritional deficiencies during pregnancy can have serious consequences for the health of the (unborn) child. This systematic review provides an updated overview of the... (Review)
Review
Nutritional deficiencies during pregnancy can have serious consequences for the health of the (unborn) child. This systematic review provides an updated overview of the available food and nutrient intake data for pregnant women in The Netherlands and an evaluation based on the current recommendations. Embase, MEDLINE, and national institute databases were used. Articles were selected if they had been published since 2008 and contained data on food consumption, nutrient intake, or the status of healthy pregnant women. A qualitative comparison was made with the 2021 Dutch Health Council recommendations and reference values. A total of 218 reports were included, representing 54 individual studies. Dietary assessments were primarily performed via food frequency questionnaires. Protein, vitamin A, thiamin, riboflavin, vitamin B, folate, vitamin B, vitamin C, iron, calcium, and magnesium intakes seemed to be adequate. For folate and vitamin D, supplements were needed to reach the recommended intake. The reasons for concern are the low intakes of fruits, vegetables, and (fatty) fish, and the intakes of alcohol, sugary drinks, and salt. For several foods and nutrients, no or limited intake data were found. High-quality, representative, and recent data are needed to evaluate the nutrient intake of pregnant women in order to make accurate assessments and evaluations, supporting scientific-based advice and national nutritional policies.
Topics: Animals; Female; Pregnancy; Humans; Pregnant Women; Netherlands; Energy Intake; Eating; Vitamins; Folic Acid; Diet
PubMed: 37447397
DOI: 10.3390/nu15133071 -
Annals of the New York Academy of... Apr 2017Adolescence is a critical stage in the life cycle, and adequate nutrition is necessary for the proper growth and development of individuals and their offspring. Here, we... (Meta-Analysis)
Meta-Analysis Review
Adolescence is a critical stage in the life cycle, and adequate nutrition is necessary for the proper growth and development of individuals and their offspring. Here, we comprehensively review all published systematic reviews (through October 2016) on adolescents (10-19 years) and women of reproductive age, including pregnant women, which targeted interventions related to nutrition. For interventions where there was no existing systematic review on adolescents, we reviewed primary studies/trials. We included interventions on micronutrient supplementation (iron, folic acid, iron-folic acid (IFA), calcium, vitamin D, vitamin A, zinc, iodine, and multiple micronutrients), food/protein energy supplementation, nutrition education for pregnant adolescents, obesity prevention and management, and management of gestational diabetes. We identified a total of 35 systematic reviews, of which only five were conducted on adolescents, and 107 primary studies on adolescents. Our review suggests that iron alone, IFA, zinc, and multiple micronutrient supplementation in adolescents can significantly improve serum hemoglobin concentration. While zinc supplementation in pregnant adolescents showed improvements in preterm birth and low birth weight, we found a paucity of trials on calcium, vitamin D, vitamin A, and iodine supplementation. We found limited evidence on food/protein energy supplementation in adolescents. Interventions to prevent and manage obesity showed a nonsignificant impact on reducing body mass index. This review underscores the importance of adolescent nutrition interventions. It is imperative that countries design nutritional interventions, particularly for adolescents.
Topics: Adolescent; Adolescent Nutritional Physiological Phenomena; Diabetes, Gestational; Dietary Supplements; Early Intervention, Educational; Early Medical Intervention; Evidence-Based Medicine; Female; Humans; Micronutrients; Nutritional Requirements; Obesity; Pregnancy
PubMed: 28436101
DOI: 10.1111/nyas.13335 -
Neuroepidemiology 2014Vitamin A and carotenoids are involved in signalling pathways regulating gene expression in many organs, including the brain. The dopaminergic system is a target of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Vitamin A and carotenoids are involved in signalling pathways regulating gene expression in many organs, including the brain. The dopaminergic system is a target of retinoic acid action in the central nervous system. The aim of this review is to assess the epidemiological evidence on the association between blood levels or dietary intakes of vitamin A and carotenoids and risk of Parkinson's disease (PD).
METHODS
PubMed and ISI Web of Science were searched for relevant papers from 1990 to April 2013. Data reported in epidemiological studies assessing the association between vitamin A and/or carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, zeaxanthin and canthaxanthin) and PD were extracted for a narrative synthesis and meta-analysis.
RESULTS
Thirteen papers were included out of a total of 362 potentially relevant; of these, eight contributed to the meta-analysis. No statistically significant pooled estimate between micronutrient and PD was detected. Forest plots suggest possible non-significant inverse pooled estimates of α-carotene and β-carotene and risk of PD. A significant association between lutein intake and PD risk was detected in case-control studies only.
CONCLUSIONS
Data published to date are insufficient for drawing definite conclusions about the epidemiological evidence on the association between blood levels or dietary intakes of vitamin A and carotenoids and the risk of PD. Results should be interpreted particularly cautiously given the limitation of the present meta-analysis and the potential publication bias. Authors are urged to follow more closely the recommendations for reporting epidemiological studies in order to enhance the capacity for synthesising the evidence.
Topics: Animals; Carotenoids; Case-Control Studies; Humans; Parkinson Disease; Risk Factors; Vitamin A; beta Carotene
PubMed: 24356061
DOI: 10.1159/000355849 -
Nutrients Mar 2018The aim of is to determine the association of vitamins with glaucoma by performing a systematic review and meta-analyses. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The aim of is to determine the association of vitamins with glaucoma by performing a systematic review and meta-analyses.
METHODS
Studies on the relation of vitamins and glaucoma published up to December 2017 were identified in the PubMed and Embase database. Data on vitamins (method of assessment), glaucoma (type and method of assessment), study characteristics and quality were recorded. In case of multiple studies for one nutrient a meta-analysis was performed.
RESULTS
A total of 629 articles were identified of which 36 were included in the systematic review. The meta-analysis included five of them (940 open-angle glaucoma (OAG) cases and 123,697 controls in total) and resulted in an odds ratio [95% confidence interval] (OR [95% CI]) of 0.58 [0.37-0.91] for dietary vitamin A, though heterogeneity was high (I² = 51%). After omitting studies that contributed significantly to the heterogeneity, the pooled OR [95% CI] was 0.45 [0.30-0.68] for dietary vitamin A on OAG (I² = 0%). For vitamin B1, C and E no significant association with OAG was found (OR [95% CI]: 0.84 [0.47-1.51]; 0.68 [0.38-1.22]; 0.95 [0.75-1.19]; respectively). However, after addressing heterogeneity, vitamin C showed a protective effect as well. Especially, foods high in these vitamins (e.g., dark green vegetables) were protective for OAG.
CONCLUSIONS
Dietary intake of vitamin A and C showed a beneficial association with OAG; however, findings on blood levels of vitamins do not show a clear relation with OAG.
Topics: Adult; Aged; Ascorbic Acid; Chi-Square Distribution; Diet; Glaucoma, Open-Angle; Humans; Middle Aged; Odds Ratio; Prevalence; Prognosis; Protective Factors; Risk Factors; Vitamin A
PubMed: 29547516
DOI: 10.3390/nu10030359