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Advances in Nutrition (Bethesda, Md.) Nov 2023Vitamin A deficiency (VAD) increases risk for morbidity and mortality. Food-based approaches offer one strategy to improve vitamin A status. This systematic review... (Review)
Review
Vitamin A deficiency (VAD) increases risk for morbidity and mortality. Food-based approaches offer one strategy to improve vitamin A status. This systematic review assessed evidence of the effects of food-based approaches on the vitamin A status of women and children under 5 y. VAD was defined as clinical ocular symptoms, such as loss of vision, and/or retinol plasma or serum concentration <0.70 μmol/L. Searches on food-based approaches to improve vitamin A status were conducted for the period 2011-2022 on PubMed, CINHAL, Web of Science, and Google Scholar using PRISMA guidelines. English-language publications were included. Case studies, unpublished dissertations, and non-peer-reviewed studies were excluded. This review comprises 24 of 27,322 identified studies; 23 included studies focused on provitamin A carotenoids. There were 17,214 participants across the 24 studies with sample sizes ranging from 8 to 3571 individuals. Intervention studies spanned from 3 wk to 2 y. Fifteen (63%) studies were randomized control trials, 7 were cross-sectional, and 2 were longitudinal studies. Most studies (N = 21) used biochemical measurements, for example, serum retinol, to assess vitamin A status; other studies used clinical symptoms (for example, xerophtalmia) or dietary intake. Thirteen (54%) studies reported a statistically significant effect of food-based interventions (N = 8) or an association of diet (N = 5) on vitamin A status. This systematic review indicated that some food-based interventions improved vitamin A status, thus offering a safe and effective delivery mechanism for vitamin A. There appeared to be significant association between vitamin A status and consumption of foods with high concentrations of preformed vitamin A and provitamin A carotenoids. Differences across studies in regard to the period of evaluation, food approaches used, and statistical power may explain the lack of effectiveness of food-based approaches on vitamin A status in some studies.
Topics: Child; Humans; Female; Vitamin A; Provitamins; Vitamin A Deficiency; Diet; Carotenoids
PubMed: 37634852
DOI: 10.1016/j.advnut.2023.08.009 -
The British Journal of Nutrition Jan 2023Inflammation and infections such as malaria affect estimates of micronutrient status. Medline, Embase, Web of Science, Scopus and the Cochrane library were searched to... (Meta-Analysis)
Meta-Analysis Review
Inflammation and infections such as malaria affect estimates of micronutrient status. Medline, Embase, Web of Science, Scopus and the Cochrane library were searched to identify studies reporting mean concentrations of ferritin, hepcidin, retinol or retinol binding protein in individuals with asymptomatic or clinical malaria and healthy controls. Study quality was assessed using the US National Institute of Health tool. Random effects meta-analyses were used to generate summary mean differences. In total, forty-four studies were included. Mean ferritin concentrations were elevated by: 28·2 µg/l (95 % CI 15·6, 40·9) in children with asymptomatic malaria; 28·5 µg/l (95 % CI 8·1, 48·8) in adults with asymptomatic malaria; and 366 µg/l (95 % CI 162, 570) in children with clinical malaria compared with individuals without malaria infection. Mean hepcidin concentrations were elevated by 1·52 nmol/l (95 % CI 0·92, 2·11) in children with asymptomatic malaria. Mean retinol concentrations were reduced by: 0·11 µmol/l (95 % CI -0·22, -0·01) in children with asymptomatic malaria; 0·43 µmol/l (95 % CI -0·71, -0·16) in children with clinical malaria and 0·73 µmol/l (95 % CI -1·11, -0·36) in adults with clinical malaria. Most of these results were stable in sensitivity analyses. In children with clinical malaria and pregnant women, difference in ferritin concentrations were greater in areas with higher transmission intensity. We conclude that biomarkers of iron and vitamin A status should be statistically adjusted for malaria and the severity of infection. Several studies analysing asymptomatic infections reported elevated ferritin concentrations without noticeable elevation of inflammation markers, indicating a need to adjust for malaria status in addition to inflammation adjustments.
Topics: Child; Adult; Humans; Female; Pregnancy; Iron; Vitamin A; Hepcidins; Vitamin A Deficiency; Nutritional Status; Malaria; Ferritins; Anemia, Iron-Deficiency; Inflammation
PubMed: 35260210
DOI: 10.1017/S0007114522000757 -
The Cochrane Database of Systematic... Mar 2020This is the second update of this Cochrane Review. Some studies have suggested a protective effect of antioxidant nutrients and higher dietary levels of fruits and... (Meta-Analysis)
Meta-Analysis
BACKGROUND
This is the second update of this Cochrane Review. Some studies have suggested a protective effect of antioxidant nutrients and higher dietary levels of fruits and vegetables on lung cancer.
OBJECTIVES
To determine whether vitamins and minerals and other potential agents, alone or in combination, reduce lung cancer incidence and lung cancer mortality in healthy populations.
SEARCH METHODS
We searched CENTRAL, MEDLINE and Embase from 1974 to May 2019 and screened references included in published studies and reviews.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) comparing vitamins or mineral supplements with placebo, administered to healthy people with the aim of preventing lung cancer.
DATA COLLECTION AND ANALYSIS
Four review authors independently selected the trials to be included in the review, assessed their methodological quality and extracted data. For dichotomous outcomes we calculated risk ratios (RRs) and 95% confidence intervals (CIs) and pooled results using the random-effects model. We assessed the risk of bias using Cochrane's 'Risk of bias' assessment tool and certainty of evidence using the GRADE approach.
MAIN RESULTS
In this update, we identified three new trials for a total of 12 studies. Six analysed vitamin A, three vitamin C, three combined vitamin D3 + calcium, four vitamin E combined with other products, one selenium supplements and nine studied combinations of two or more products. Four studies included only men and five only women. Vitamin A results in little to no difference in lung cancer incidence (RR 1.09, 95% CI 1.00 to 1.19; 5 RCTs, 212314 participants; high-certainty evidence) and lung cancer mortality (RR 1.06, 95% CI 0.81 to 1.38; 3 RCTs, 190118 participants; high-certainty evidence). But in smokers or asbestos workers vitamin A increases the risk of lung cancer incidence (RR 1.10, 95% CI 1.01 to 1.20; 3 RCTs, 43995 participants; high-certainty evidence), lung cancer mortality (RR 1.18, 95% CI 1.01 to 1.38; 2 RCTs, 29426 participants; high-certainty evidence) and all-cause mortality (RR 1.09, 95% CI 1.05 to 1.13; 2 RCTs, 32883 participants; high-certainty evidence). Vitamin A increases the risk of minor side effects, such as yellowing of the skin and minor gastrointestinal symptoms (high-certainty evidence). Vitamin C likely results in little to no difference in lung cancer incidence (RR 1.29, 95% CI 0.67 to 2.49; 2 RCTs, 14953 participants; moderate-certainty evidence). In women, vitamin C increases the risk of lung cancer incidence (RR 1.84, 95% CI 1.14 to 2.95; 1 RCT, 7627 participants; high-certainty evidence). In men, vitamin C results in little to no difference in mortality for lung cancer (RR 0.81, 95% CI 0.53 to 1.23; 1 RCT, 7326 participants; high-certainty evidence). Vitamin D + calcium may result in little to no difference in lung cancer incidence in postmenopausal women (RR 0.90, 95% CI 0.39 to 2.08; 3 RCTs, 37601 women; low-certainty evidence). Vitamin E results in little to no difference in lung cancer incidence (RR 1.01, 95% CI 0.90 to 1.14; 3 RCTs, 36841 participants; high-certainty evidence) or to lung cancer mortality (RR 0.96, 95% CI 0.77 to 1.18; 2 RCTs, 29214 participants; high-certainty evidence), but increases the risk of haemorrhagic strokes (hazard ratio (HR), 1.74, 95% CI 1.04 to 2.91; 1 RCT, 14641 participants; high-certainty evidence). Calcium results in little to no difference in lung cancer incidence in postmenopausal women (RR 0.65, 95% CI 0.13 to 3.18; 1 RCT, 733 participants) or in risk of renal calculi (RR 1.94, 95% CI 0.20 to 18.57; 1 RCT, 733 participants; low-certainty evidence). Selenium in men results in little to no difference in lung cancer incidence (RR 1.11, 95% CI 0.80 to 1.54; 1 RCT, 17448 participants; high-certainty evidence) and lung cancer mortality (RR 1.09, 95% CI 0.72 to 1.66; 1 RCT, 17448 participants; high-certainty evidence) and increases the risk for grade 1 to 2 dermatitis (RR 1.16, 95% CI 1.04 to 1.31; 1 RCT, 17448 participants; high-certainty evidence) and for alopecia (RR 1.28, 95% CI 1.07 to 1.53; 1 RCT, 17448 participants; high-certainty evidence). The combination of vitamins A, C, E + selenium + zinc results in little to no difference in lung cancer incidence (RR 0.64, 95% CI 0.28 to 1.48; 1 RCT, 12741 participants; high-certainty evidence).
AUTHORS' CONCLUSIONS
Well-designed RCTs have shown no beneficial effect of supplements for the prevention of lung cancer and lung cancer mortality in healthy people. Vitamin A supplements increase lung cancer incidence and mortality in smokers or persons exposed to asbestos. Vitamin C increases lung cancer incidence in women. Vitamin E increases the risk of haemorrhagic strokes.
Topics: Ascorbic Acid; Calcium, Dietary; Cholecalciferol; Confidence Intervals; Dietary Supplements; Female; Health Status; Humans; Incidence; Lung Neoplasms; Male; Minerals; Randomized Controlled Trials as Topic; Selenium; Selenium Compounds; Sex Factors; Vitamin A; Vitamin E; Vitamins; alpha-Tocopherol; beta Carotene
PubMed: 32130738
DOI: 10.1002/14651858.CD002141.pub3 -
Food Chemistry Aug 2022Considering that antioxidant activities are directly related to carotenoid functionalities, it is necessary to use techniques that promote the stability of these natural... (Review)
Review
Considering that antioxidant activities are directly related to carotenoid functionalities, it is necessary to use techniques that promote the stability of these natural pigments. This systematic review aimed to gather evidence on the effect of encapsulation techniques on the maintenance and/or enhancement of the antioxidant activity of carotenoids. The study was registered in PROSPERO (CRD42020142065). Searches were performed in PubMed, Embase, Virtual Health Library, Scopus, ScienceDirect, and Web of Science databases. Assessment of methodological quality was performed using OHAT. A total of 1577 articles were selected, resulting in 20 eligible studies. Overall, results showed that the mechanisms involved are related to the emergence of new chemical interactions, increased surface area, and the controlled release of carotenoids. Thus, evidence proved that encapsulation could preserve and/or enhance bioactivities of carotenoids, allowing the use in foods to promote benefits on population health.
Topics: Antioxidants; Carotenoids; Food
PubMed: 35276479
DOI: 10.1016/j.foodchem.2022.132593 -
Nutrients Oct 2023Bread is among the most common foods for the world's population. Therefore, it can be fortified to eliminate deficiencies of nutrients or be a carrier of other... (Review)
Review
Bread is among the most common foods for the world's population. Therefore, it can be fortified to eliminate deficiencies of nutrients or be a carrier of other substances with a nutritional or physiological effect, bringing health benefits to its consumers, thus impacting sustainable health. This systematic review aimed to analyze clinical studies on the effects of bread fortification on human health. The study followed the PRISMA guidelines for transparency and utilized databases Scopus, Embase, PubMed, and Web of Science to search clinical trials focused on the effects of bread fortification on human health over the entire last decade. The methodological quality of selected studies was assessed using the Jadad scale. As a result, twenty-six studies meet the inclusion criteria. Clinical trials have shown health benefits from consuming bread fortified with vitamins (B, C, D, D), minerals (K, P, Ca, Mg, Fe, Zn, Cr, Se), fiber, proteins, and polyphenolic compounds. Conclusions reveal that mandatory fortification aligns with the sustainable development goals. Thus, collaborative partnerships are essential for successful implementation and accessibility, fostering public health advances and progress developing into sustainable health.
Topics: Humans; Bread; Food, Fortified; Vitamins; Minerals; Vitamin A
PubMed: 37892534
DOI: 10.3390/nu15204459 -
Nutrients Mar 2020Suboptimal nutritional status of a newborn is a risk factor for short- and long-term morbidity and mortality. The objectives of this review were to assess the efficacy... (Meta-Analysis)
Meta-Analysis
Effect of Synthetic Vitamin A and Probiotics Supplementation for Prevention of Morbidity and Mortality during the Neonatal Period. A Systematic Review and Meta-Analysis of Studies from Low- and Middle-Income Countries.
Suboptimal nutritional status of a newborn is a risk factor for short- and long-term morbidity and mortality. The objectives of this review were to assess the efficacy and effectiveness of neonatal synthetic vitamin A supplementation, dextrose gel and probiotic supplementation for prevention of morbidity and mortality during infancy in low and middle-income countries. We included randomized trials. Primary outcome was all-cause mortality. We conducted electronic searches on multiple databases. Data were meta-analyzed to obtain relative risk (RR) and 95% confidence interval (CI). Studies for vitamin A and Probiotics were analyzed separately. No studies were found for dextrose gel supplementation during neonatal period. The overall rating of evidence was determined by Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Sixteen studies assessed the effect of vitamin A supplementation during the neonatal period. Based on pooled data from community-based studies only, there was no significant effect of vitamin A on all-cause mortality at age 1 month (RR 0.99, 95% CI 0.90, 1.08), 6 months (RR 0.98; 95% CI 0.89-1.08) and 12 months (RR 1.04, 95% CI 0.94, 1.14) but increased risk of bulging fontanelle (RR 1.53, 95% CI 1.12, 2.09). The overall quality of evidence was high for the above outcomes. Thirty-three studies assessed the effect of probiotic supplementation during the neonatal period and were mostly conducted in the hospital setting. Probiotics reduced the risk of all-cause mortality (RR 0.80, 95% CI 0.66, 0.96), necrotizing enterocolitis (RR 0.46, 95% CI 0.35, 0.59) and neonatal sepsis (RR 0.78, 95% CI 0.70, 0.86). The grade ratings for the above three outcomes were high. Vitamin A supplementation during the neonatal period does not reduce all-cause neonatal or infant mortality in low and middle-income countries in the community setting. Probiotic supplementation during the neonatal period seems to reduce all-cause mortality, NEC, and sepsis in babies born low birth weight and/or preterm in the hospital setting.
Topics: Developing Countries; Enterocolitis, Necrotizing; Humans; Infant; Infant Mortality; Infant, Newborn; Nutritional Status; Probiotics; Randomized Controlled Trials as Topic; Sepsis; Vitamin A
PubMed: 32192165
DOI: 10.3390/nu12030791 -
Advances in Nutrition (Bethesda, Md.) May 2020Some evidence indicates that carotenoids may reduce the risk of bladder cancer (BC), but the association is unclear. We conducted a systematic review and meta-analysis... (Meta-Analysis)
Meta-Analysis
Some evidence indicates that carotenoids may reduce the risk of bladder cancer (BC), but the association is unclear. We conducted a systematic review and meta-analysis of case-control and cohort studies investigating the relation between carotenoid intake or circulating carotenoid concentrations and BC risk in men and women. All relevant epidemiologic studies were identified by a search of PubMed and Scopus databases, and the Cochrane Library from inception to April 2019 with no restrictions. A random-effects model was used to calculate pooled RRs and their 95% CIs across studies for high compared with low categories of intake or circulating concentrations. We also performed a dose-response meta-analysis using the Greenland and Longnecker method and random-effects models. A total of 22 studies involving 516,740 adults were included in the meta-analysis. The pooled RRs of BC for the highest compared with the lowest category of carotenoid intake and circulating carotenoid concentrations were 0.88 (95% CI: 0.76, 1.03) and 0.36 (95% CI: 0.12, 1.07), respectively. The pooled RR of BC for the highest compared with lowest circulating lutein and zeaxanthin concentrations was 0.53 (95% CI: 0.33, 0.84). Dose-response analysis showed that BC risk decreased by 42% for every 1 mg increase in daily dietary β-cryptoxanthin intake (RR: 0.58; 95% CI: 0.36, 0.94); by 76% for every 1 μmol/L increase in circulating concentration of α-carotene (RR: 0.24; 95% CI: 0.08, 0.67); by 27% for every 1 μmol/L increase in circulating concentration of β-carotene (RR: 0.73; 95% CI: 0.57, 0.94); and by 56% for every 1 μmol/L increase in circulating concentrations of lutein and zeaxanthin (RR: 0.44; 95% CI: 0.28, 0.67). Dietary β-cryptoxanthin intake and circulating concentrations of α-carotene, β-carotene, and lutein and zeaxanthin were inversely associated with BC risk. The protocol was registered at PROSPERO as CRD42019133240.
Topics: Adult; Carotenoids; Female; Humans; Lutein; Male; Urinary Bladder Neoplasms; Zeaxanthins; beta Carotene
PubMed: 31800007
DOI: 10.1093/advances/nmz120 -
European Journal of Trauma and... Dec 2022High clinical success rates have been reported with the Masquelet technique in the treatment of traumatic bone loss. An increasing number of studies suggest that various... (Review)
Review
PURPOSE
High clinical success rates have been reported with the Masquelet technique in the treatment of traumatic bone loss. An increasing number of studies suggest that various factors can influence the properties of induced membranes. Goal of this systematic review is to answer the following questions: (1) which are the ideal spacer properties (material, surface topography, antibiotic supplementation) to booster the quality and osteogenic potential of induced membranes? (2) what is the ideal time to perform the second-stage operation?
METHODS
A systematic search using the keywords "((Masquelet) OR (Induced Periosteum)) AND ((Spacer) OR (Time))" was performed in PubMed, Embase and Cochrane Library according to PRISMA guidelines. Studies published up to the 23rd of February 2022 were included and assessed independently by two reviewers.
RESULTS
Thirteen animal and 1 clinical studies were identified to address the above questions. Spacer materials used were PMMA, silicone, titanium, polypropylene, PVA, PCL and calcium sulfate. With the exception of PVA sponges, all solid materials could induce membranes. Low union rates have been reported with titanium and rough surfaced spacers. Scraping of the inner surface of the IM also increased bony union rates. In terms of the ideal timing to perform the second-stage evidence suggests that membranes older than 8 weeks continue to have regenerative capacities similar to younger ones.
CONCLUSION
Membranes induced by smooth PMMA spacers loaded with low concentrations of antibiotics showed powerful osteogenic properties. Other materials such as Polypropylene or Calcium sulfate can also be used with good results. Despite current recommendation to perform the second stage operation in 4-8 weeks, membranes older than 8 weeks seem to have similar regenerative capacities to younger ones.
Topics: Animals; Polymethyl Methacrylate; Titanium; Calcium Sulfate; Polypropylenes
PubMed: 35726029
DOI: 10.1007/s00068-022-02005-x -
Nutrients Jun 2021Primary open-angle glaucoma (POAG) remains a leading cause of irreversible blindness globally. Recent evidence further substantiates sustained oxidative stress, and...
Primary open-angle glaucoma (POAG) remains a leading cause of irreversible blindness globally. Recent evidence further substantiates sustained oxidative stress, and compromised antioxidant defenses are key drivers in the onset of glaucomatous neurodegeneration. Overwhelming oxidative injury is likely attributed to compounding mitochondrial dysfunction that worsens with age-related processes, causing aberrant formation of free radical species. Thus, a compromised systemic antioxidant capacity exacerbates further oxidative insult in glaucoma, leading to apoptosis, neuroinflammation, and subsequent tissue injury. The purpose of this systematic review is to investigate the neuroprotective benefits of the macular carotenoids lutein, zeaxanthin, and -zeaxanthin on glaucomatous neurodegeneration for the purpose of adjunctive nutraceutical treatment in glaucoma. A comprehensive literature search was conducted in three databases (PubMed, Cochrane Library, and Web of Science) and 20 records were identified for screening. Lutein demonstrated enhanced neuroprotection on retinal ganglion cell survival and preserved synaptic activity. In clinical studies, a protective trend was seen with greater dietary consumption of carotenoids and risk of glaucoma, while greater carotenoid levels in macular pigment were largely associated with improved visual performance in glaucomatous eyes. The data suggest that carotenoid vitamin therapy exerts synergic neuroprotective benefits and has the capacity to serve adjunctive therapy in the management of glaucoma.
Topics: Antioxidants; Carotenoids; Dietary Supplements; Glaucoma, Open-Angle; Humans; Lutein; Macular Pigment; Oxidative Stress; Visual Acuity; Zeaxanthins
PubMed: 34204051
DOI: 10.3390/nu13061949 -
BMJ Open May 2024This systematic review with meta-analyses of randomised trials evaluated the preventive effects of vitamin A supplements versus placebo or no intervention on clinically... (Meta-Analysis)
Meta-Analysis
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.
OBJECTIVES
This systematic review with meta-analyses of randomised trials evaluated the preventive effects of vitamin A supplements versus placebo or no intervention on clinically important outcomes, in people of any age.
METHODS
We searched different electronic databases and other resources for randomised clinical trials that had compared vitamin A supplements versus placebo or no intervention (last search 16 April 2024). We used Cochrane methodology. We used the random-effects model to calculate risk ratios (RRs), with 95% CIs. We analysed individually and cluster randomised trials separately. Our primary outcomes were mortality, adverse events and quality of life. We assessed risks of bias in the trials and used Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) to assess the certainty of the evidence.
RESULTS
We included 120 randomised trials (1 671 672 participants); 105 trials allocated individuals and 15 allocated clusters. 92 trials included children (78 individually; 14 cluster randomised) and 28 adults (27 individually; 1 cluster randomised). 14/105 individually randomised trials (13%) and none of the cluster randomised trials were at overall low risk of bias. Vitamin A did not reduce mortality in individually randomised trials (RR 0.99, 95% CI 0.93 to 1.05; I=32%; p=0.19; 105 trials; moderate certainty), and this effect was not affected by the risk of bias. In individually randomised trials, vitamin A had no effect on mortality in children (RR 0.96, 95% CI 0.88 to 1.04; I=24%; p=0.28; 78 trials, 178 094 participants) nor in adults (RR 1.04, 95% CI 0.97 to 1.13; I=24%; p=0.27; 27 trials, 61 880 participants). Vitamin A reduced mortality in the cluster randomised trials (0.84, 95% CI 0.76 to 0.93; I=66%; p=0.0008; 15 trials, 14 in children and 1 in adults; 364 343 participants; very low certainty). No trial reported serious adverse events or quality of life. Vitamin A slightly increased bulging fontanelle of neonates and infants. We are uncertain whether vitamin A influences blindness under the conditions examined.
CONCLUSIONS
Based on moderate certainty of evidence, vitamin A had no effect on mortality in the individually randomised trials. Very low certainty evidence obtained from cluster randomised trials suggested a beneficial effect of vitamin A on mortality. If preventive vitamin A programmes are to be continued, supporting evidence should come from randomised trials allocating individuals and assessing patient-meaningful outcomes.
PROSPERO REGISTRATION NUMBER
CRD42018104347.
Topics: Humans; Vitamin A; Randomized Controlled Trials as Topic; Dietary Supplements; Primary Prevention; Secondary Prevention; Quality of Life; Vitamins
PubMed: 38816049
DOI: 10.1136/bmjopen-2023-078053