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Hepatology (Baltimore, Md.) Mar 2024The association between fiber or whole grain intakes and the risk of liver cancer remains unclear. We assessed the associations between fiber or whole grain intakes and...
BACKGROUND AND AIMS
The association between fiber or whole grain intakes and the risk of liver cancer remains unclear. We assessed the associations between fiber or whole grain intakes and liver cancer risk among 2 prospective studies, and systematically reviewed and meta-analyzed these results with published prospective studies.
APPROACH AND RESULTS
A total of 111,396 participants from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) and 26,085 men from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study were included. Intakes of total fiber and whole grains were estimated from validated food frequency questionnaires. Study-specific HRs and 95% CI with liver cancer risk were estimated using multivariable-adjusted Cox regression. We systematically reviewed existing literature, and studies were combined in a dose-response meta-analysis. A total of 277 (median follow-up = 15.6 y) and 165 (median follow-up = 16.0 y) cases of liver cancer were observed in Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial and Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, respectively. Dietary fiber was inversely associated with liver cancer risk in Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (HR 10g/day : 0.69; 95% CI: 0.55-0.86). No significant associations were observed between whole grain intakes and liver cancer risk in either study. Our meta-analysis included 2383 incident liver cancer cases (7 prospective cohorts) for fiber intake and 1523 cases (5 prospective cohorts) for whole grain intake; combined HRs for liver cancer risk were 0.83 (0.76-0.91) per 10 g/day of fiber and 0.92 (0.85-0.99) per 16 g/day (1 serving) of whole grains.
CONCLUSIONS
Dietary fiber and whole grains were inversely associated with liver cancer risk. Further research exploring potential mechanisms and different fiber types is needed.
PubMed: 38441973
DOI: 10.1097/HEP.0000000000000819 -
International Journal For Vitamin and... Dec 2015The purpose of this study is to systematically review the published literature reporting vitamin E intake levels and serum concentrations in order to obtain a global...
The purpose of this study is to systematically review the published literature reporting vitamin E intake levels and serum concentrations in order to obtain a global overview of α-tocopherol status. Articles published between 2000 and 2012 were considered; 176 articles referring to 132 single studies were included. Applying an RDA (recommended daily allowance) of 15 mg/day and EAR (estimated average requirement) of 12 mg/day to all populations with a minimum age of 14 years, 82 and 61 % of mean and median data points were below the RDA and the EAR, respectively. Regarding serum concentrations, globally 13 % of the included data points were below the functional deficiency threshold concentration of 12 µmol/L, mostly for newborns and children. Several prospective observational studies suggest that a serum α-tocopherol concentration of ≥30 µmol/L has beneficial effects on human health. Of the reported study populations and subpopulations, only 21 % reached this threshold globally. This systematic review suggests that the α-tocopherol status is inadequate in a substantial part of the studied populations.
PubMed: 27414419
DOI: 10.1024/0300-9831/a000281 -
Surgery For Obesity and Related... Apr 2021Vitamin E, a fat-soluble vitamin with antioxidant properties, is thought to modulate enzymes involved in signal transduction, affect gene expression, and have... (Review)
Review
Vitamin E, a fat-soluble vitamin with antioxidant properties, is thought to modulate enzymes involved in signal transduction, affect gene expression, and have immunomodulatory capabilities. Severe vitamin E deficiency is associated with neuronal disorders, impaired immune response, hemolytic anemia, and oxidative-based disorders. Patients who undergo bariatric surgery (BS), especially malabsorptive procedures, are at greater risk of developing fat-soluble vitamin deficiencies. Current data on vitamin E statuses among BS patients are limited. Therefore, this systematic review has summarized the scientific literature on vitamin E and examined its status among patients following different types of BS. Searches of the MEDLINE and Embase databases were performed, followed by hand-searching of reference lists from all relevant papers. Of the 671 initially identified articles, 24 met the inclusion criteria: 1 study on adjustable gastric banding patients (n = 21), 4 studies on sleeve gastrectomy patients (n = 173), 12 studies on Roux-en-Y gastric bypass patients (n = 689) and 12 studies on biliopancreatic diversion with or without duodenal switch (n = 799) or single anastomosis duodeno-ileal bypass with sleeve gastrectomy patients (n = 163). Results suggest that patients who undergo malabsorptive procedures are at higher risk of developing vitamin E deficiency, although clinical manifestations of vitamin E deficits following BS are rarely documented. The optimal dose of vitamin E supplementation required for prevention of deficiency or for treatment following BS has yet to be established. Future observational and intervention studies are needed to bridge the gaps in existing knowledge.
Topics: Bariatric Surgery; Biliopancreatic Diversion; Gastrectomy; Gastric Bypass; Humans; Obesity, Morbid; Vitamin E
PubMed: 33323330
DOI: 10.1016/j.soard.2020.10.029 -
Nutrients Feb 2023The increasing burden of nonalcoholic fatty liver disease (NAFLD) requires innovative management strategies, but an effective pharmacological agent has yet to be found.... (Review)
Review
The increasing burden of nonalcoholic fatty liver disease (NAFLD) requires innovative management strategies, but an effective pharmacological agent has yet to be found. Apart from weight loss and lifestyle adjustments, one isomer of the vitamin E family-alpha-tocopherol-is currently recommended for nondiabetic steatohepatitis patients. Another member of the vitamin E family, tocotrienol (T3), has anti-inflammatory and antioxidant properties that reach beyond those of alpha-tocopherol, making it a potential agent for use in NAFLD management. This systematic review aimed to provide an overview of the effects of T3 supplementation on NAFLD from both clinical and preclinical perspectives. A literature search was performed in October 2022 using PubMed, Scopus and Web of Science. Original research articles reporting NAFLD outcomes were included in this review. The search located 12 articles (8 animal studies and 4 human studies). The literature reports state that T3 isomers or natural mixtures (derived from palm or annatto) improved NAFLD outcomes (liver histology, ultrasound or liver profile). However, the improvement depended on the severity of NAFLD, study period and type of intervention (isomers/mixture of different compositions). Mechanistically, T3 improved lipid metabolism and prevented liver steatosis, and reduced mitochondrial and endoplasmic reticulum stress, inflammation and ultimately liver fibrosis. In summary, T3 could be a potential agent for use in managing NAFLD, pending more comprehensive preclinical and human studies.
Topics: Animals; Humans; Non-alcoholic Fatty Liver Disease; Tocotrienols; alpha-Tocopherol; Liver; Vitamin E
PubMed: 36839192
DOI: 10.3390/nu15040834 -
Atherosclerosis Dec 2015Vitamin E is one of the most important natural antioxidants, and its plasma levels are inversely associated with the progression of atherosclerosis. There have been... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Vitamin E is one of the most important natural antioxidants, and its plasma levels are inversely associated with the progression of atherosclerosis. There have been reports suggesting a potential negative effect of statin therapy on plasma vitamin E levels. The aim of this meta-analysis was to determine the impact of statin therapy on plasma vitamin E concentrations.
METHODS
PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases were searched to identify randomized placebo-controlled trials evaluating the impact of statins on plasma vitamin E concentrations from inception to February 27, 2015. A systematic assessment of bias in the included studies was performed using the Cochrane criteria. A random-effects model (using DerSimonian-Laird method) and the generic inverse variance method were used to examine the effect of statins on plasma vitamin E concentrations. Heterogeneity was quantitatively assessed using the I(2) index. Sensitivity analysis was conducted using the leave-one-out method.
RESULTS
A meta-analysis of data from 8 randomized treatment arms including 504 participants indicated a significant reduction in plasma vitamin E concentrations following statin treatment (WMD: -16.30%, 95% CI: -16.93, -15.98, p < 0.001). However, cholesterol-adjusted vitamin E concentrations (defined as vitamin E:total cholesterol ratio) were found to be improved by statin therapy (WMD: 29.35%, 95% CI: 24.98, 33.72, p < 0.001). Statin therapy was not associated with any significant alteration in LDL vitamin E content (SMD: 0.003, 95% CI: -0.90, 0.90, p = 0.995).
CONCLUSION
Findings of the present study suggest that statin therapy has no negative impact on plasma vitamin E concentrations or LDL vitamin E content.
Topics: Antioxidants; Atherosclerosis; Biomarkers; Dyslipidemias; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Lipids; Randomized Controlled Trials as Topic; Treatment Outcome; Vitamin E
PubMed: 26539697
DOI: 10.1016/j.atherosclerosis.2015.09.028 -
Clinical Nutrition ESPEN Dec 2021Cardiovascular diseases (CVDs) are the number one cause of mortality worldwide. Apolipoprotein B (ApoB), apolipoprotein A1 (ApoA1), and ApoB/ApoA1 ratio are considered... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND AIM
Cardiovascular diseases (CVDs) are the number one cause of mortality worldwide. Apolipoprotein B (ApoB), apolipoprotein A1 (ApoA1), and ApoB/ApoA1 ratio are considered as predictors of CVD alongside with lipid profile. Evidence suggest that nutrients with antioxidant properties, especially vitamin E, are essential for a healthy cardiovascular system. The aim of present meta-analysis was to determine the effect alpha-tocopherol on ApoA1 and ApoB levels.
METHODS
PubMed-Medline and SCOPUS databases and Google Scholar were searched up to July 2021. Random-effects model was employed to perform meta-analysis. In order to find heterogeneity sources, subgroup analysis was performed. Trim and fill analysis was performed in case of presence of publication bias. Quality assessment was performed using Cochrane Collaboration's tool.
RESULTS
Seven eligible studies, involving 1284 individuals were included. Mean age of participants ranged between 25.4 and 59 years. There was no significant effect of vitamin E supplementation on Apo A1 (SMD = 0.22 IU/d; 95% CI: -0.38, 0.28; P = 0.481) and Apo B levels (SMD = -0.62 IU/d; 95% CI: -1.94, 0.70; P = 0.360).
CONCLUSION
No remarkable effect of vitamin E supplementation was observed on ApoA1 and ApoB levels in adults. Additional studies investigating the influence of vitamin E on apolipoproteins as primary outcome with larger sample size are suggested.
Topics: Adult; Antioxidants; Apolipoprotein A-I; Apolipoproteins; Dietary Supplements; Humans; Middle Aged; Vitamin E
PubMed: 34857183
DOI: 10.1016/j.clnesp.2021.09.013 -
Sao Paulo Medical Journal = Revista... 2021Despite the several options available for supplements containing vitamins C and E, evidence regarding the prevalence of deficiency or insufficiency of these vitamins is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Despite the several options available for supplements containing vitamins C and E, evidence regarding the prevalence of deficiency or insufficiency of these vitamins is weak.
OBJECTIVES
To estimate the prevalence of deficiency or insufficiency of vitamins C and E and associated factors among women of childbearing age, in Brazil.
DESIGN AND SETTING
Systematic review and meta-analysis conducted at a Brazilian public university.
METHODS
A search from index inception until May 2020 was conducted. Meta-analyses were performed using inverse variance for fixed models, with summary proportions calculation using Freeman-Tukey double arcsine (base case). Reporting and methodological quality were assessed using the Joanna Briggs Institute tool for prevalence studies.
RESULTS
Our review identified 12 studies, comprising 1,316 participants, especially breastfeeding women. There was at least one quality weakness in all studies, mainly regarding sampling method (i.e. convenience sampling) and small sample size. The prevalence of vitamin C deficiency ranged from 0% to 40%. Only vitamin E deficiency was synthetized in meta-analyses, with mean prevalences of 6% regardless of the alpha-tocopherol cutoff in plasma, and 5% and 16% for cutoffs of < 1.6-12.0 mmol/l and < 16.2 mmol/l, respectively. The cumulative meta-analysis suggested that a trend to lower prevalence of vitamin E deficiency occurred in recent studies.
CONCLUSIONS
Although the studies identified in this systematic review had poor methodological and reporting quality, mild-moderate vitamin C and E deficiencies were identified, especially in breastfeeding women. Thus, designing and implementing policies does not seem to be a priority, because the need has not been properly dimensioned among women of childbearing age in Brazil.
REGISTRATION NUMBER IN PROSPERO
CRD42020221605.
Topics: Ascorbic Acid; Brazil; Dietary Supplements; Female; Humans; Prevalence; Vitamins
PubMed: 34586287
DOI: 10.1590/1516-3180.2020.0799.R1.0904221 -
Frontiers in Nutrition 2022This study systematized information about vitamin E concentration in healthy breast milk during different stages of lactation in order to support the strategies of...
OBJECTIVE
This study systematized information about vitamin E concentration in healthy breast milk during different stages of lactation in order to support the strategies of protecting postpartum women and infants.
METHODS
Studies published before April 30th, 2021, which detected vitamin E concentration in breast milk of healthy women by High Performance Liquid Chromatography (HPLC) or Ultra High Performance Liquid Chromatographic (UHPLC), were evaluated. The databases of CNKI (Chinese), WanFang Data (Chinese), VIP (Chinese), PubMed, Cochrane Library, Web of Science and Embase were searched. The random effect models were used to conduct meta-analysis by the statistical software package Stata 14.0.
RESULTS
In all 4,791 searched publications, 53 with full text were selected, which included 46 descriptive studies, 1 case-control study, 1 non-randomized controlled trial, and 5 randomized controlled trials. The pooled mean of vitamin E concentration was 10.57 mg α-TE/L (95%CI 8.94-12.20) in colostrum, 4.03 mg α-TE/L (95%CI 3.29-4.77) in transitional milk and 3.29 mg α-TE/L (95%CI 2.95-3.64) in mature milk. Subgroup analysis showed that vitamin E concentration of colostrum in Asian countries was lower than that in Western countries in colostrum and transitional milk.
CONCLUSIONS
Vitamin E concentration in breast milk decreased during lactation until the mature milk was produced. The vitamin E concentration of colostrum in Asian countries was evidently lower than that in Western countries. The vitamin E concentration in mature milk is similar in different regions. The concentration of vitamin E in breast milk started to be stable from about 2 to 3 weeks postpartum until 4 or 6 months postpartum, but it needs additional evidence to support.
PubMed: 36438759
DOI: 10.3389/fnut.2022.1050011 -
Could Vitamin E Prevent Contrast-Induced Acute Kidney Injury? A Systematic Review and Meta-Analysis.Journal of Korean Medical Science Sep 2017Several clinical studies have proposed a protective role for vitamin E (α-tocopherol) against contrast-induced acute kidney injury (CIAKI). The aim of study was to... (Meta-Analysis)
Meta-Analysis Review
Several clinical studies have proposed a protective role for vitamin E (α-tocopherol) against contrast-induced acute kidney injury (CIAKI). The aim of study was to assess the effects of vitamin E for the prevention of CIAKI. A systematic review and meta-analysis was conducted using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. Randomized controlled trials (RCTs) reporting the effects of vitamin E on CIAKI development and measurements of renal function were included. Four trials including 623 participants were analyzed in the meta-analysis. All participants received intravenous hydration in addition to vitamin E or placebo. The incidence of the vitamin E group (5.8%) was lower than that of the control group (15.4%). Compared with the control, vitamin E significantly reduced the risk ratio (RR) of CIAKI by 62% (0.38; 95% confidence interval [CI], 0.22, 0.63; P < 0.010). In addition, vitamin E reduced serum creatinine (SCr) increase after contrast administration (standardized mean difference [SMD], -0.27; 95% CI, -0.49, -0.06; P = 0.010). However, changes in glomerular filtration rate (GFR) after contrast administration were not significantly different between vitamin E and the control group (SMD, 0.21; 95% CI, -0.01, 0.43; P = 0.060). Heterogeneity within the available trials was not observed. Our meta-analysis provides evidence that vitamin E plus hydration significantly reduced the risk of CIAKI in patients with renal impairment compared with hydration alone.
Topics: Acute Kidney Injury; Administration, Intravenous; Contrast Media; Creatinine; Databases, Factual; Glomerular Filtration Rate; Humans; Risk; Vitamin E
PubMed: 28776342
DOI: 10.3346/jkms.2017.32.9.1468 -
JPMA. the Journal of the Pakistan... Jun 2024To compare the efficacy of tocotrienol and tocopherol in the management of patients with atherosclerotic cardiovascular diseases. (Comparative Study)
Comparative Study
OBJECTIVE
To compare the efficacy of tocotrienol and tocopherol in the management of patients with atherosclerotic cardiovascular diseases.
METHODS
The systematic review was conducted in line with Preferred Reporting Items for Systematic Reviews and Meta- Analyses guidelines 2020, and comprised literature search from 2002 till January 5, 2023, on PubMed, Google Scholar, Cochrane Library, Google, Wiley-Inter Science Library, Medline, SpringerLink, Taylor and Francis databases. The search was conducted using key words, such as: "tocopherol", "tocotrienol", "vitamin E", "dyslipidaemia", "cardiovascular diseases" "cardioprotective", "hypercholesterolemia" and "atherosclerosis" along with Boolean operators. Human clinical studies regarding the use of tocotrienol or tocopherol or comparison of its efficacy in patients having atherosclerosis, dyslipidaemia leading to cardiovascular diseases, and studies including details of efficacy of any of the four alpha, beta, gamma, delta isomers of tocopherol or tocotrienol were included. Pertinent data from the eligible studies was retrieved and reviewed.
RESULTS
Of the 516 articles identified, 26 (5%) articles met eligibility criteria. Of them 5(19%) were subjected to detailed analysis. Tocotrienol showed significant anti-oxidant efficacy at (250 mg/d) by decreasing cholesterol and serum inflammatory biomarkers i.e C-reactive protein (40%), malondialdehyde (34%), gamma-glutamyl transferase (22%) (p<0.001). Total anti-oxidant status (TAS) levels raised 22% (p<0.001) and Inflammatory cytokines i.e resistin, interleukin (IL)-1, IL-12, Interferon-gamma were decreased 15-17% (p<0.05-0.01) respectively by tocotrienol. Several microRNA (miRNA-133a, miRNA-223, miRNA-214, miRNA-155) were modulated by δ-tocotrienol. Whereas, tocopherol showed heterogeneity of results by either decreasing or increasing the risk of mortality in atherosclerotic cardiovascular diseases.
CONCLUSION
Compared to tocopherol, tocotrienol was found to be safe and potential candidate for improving cardiovascular health in the management of atherosclerotic cardiovascular diseases.
Topics: Humans; Tocotrienols; Atherosclerosis; Tocopherols; Antioxidants; Cardiovascular Diseases; Dyslipidemias; Cholesterol
PubMed: 38948984
DOI: 10.47391/JPMA.9227