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Frontiers in Endocrinology 2023The aim was to conduct a systematic review and meta-analysis for assessing the effectiveness and safety of dietary polyphenol curcumin supplement on metabolic,... (Meta-Analysis)
Meta-Analysis Review
Effects of dietary polyphenol curcumin supplementation on metabolic, inflammatory, and oxidative stress indices in patients with metabolic syndrome: a systematic review and meta-analysis of randomized controlled trials.
OBJECTIVE
The aim was to conduct a systematic review and meta-analysis for assessing the effectiveness and safety of dietary polyphenol curcumin supplement on metabolic, inflammatory, and oxidative stress indices in patients with metabolic syndrome (MetS).
METHODS
A comprehensive search for clinical trials was conducted in the following scientific databases: PubMed, SCOPUS, Cochrane Library, EMBASE, Web of Science, and China Biological Medicine. Randomized controlled trials (RCTs) evaluating the efficacy and safety of curcumin supplement for MetS were identified. A random-effects meta-analysis was performed using inverse variance, and efficacy was expressed as mean difference (MD) with 95% confidence interval (CI). The metabolic syndrome markers that were evaluated in the present study included waist circumference (WC), fasting blood sugar (FBS), systolic blood pressure (SBP), diastolic blood pressure (DBP), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), tumor necrosis factor-a (TNF-a), interleukin 6 (IL-6), C-reactive protein (CRP), ultrasensitive c-reactive protein (hsCRP), and malondialdehyde (MDA). By employing the Cochrane tool, RCTs were assessed for bias risk.
RESULTS
A total of 785 participants from 13 RCTs were included, with intervention durations ranging from 4 to 12 weeks. Compared with the control group, the curcumin group had positive effects on WC (MD = -2.16, 95% CI: -3.78 to -0.54, = 0.009, seven studies), FBS (MD = -8.6, 95% CI: -15.45 to -1.75, = 0.01, nine studies), DBP (MD = -2.8, 95% CI: -4.53 to - 1.06, = 0.002, five studies), HDL-C (MD = 4.98, 95% CI: 2.58 to 7.38, < 0.0001, eight studies), TNF-a (MD = -12.97, 95% CI: -18.37 to -7.57, < 0.00001, two studies), CRP (MD = - 1.24, 95% CI: -1.71 to -0.77, < 0.00001, two studies), and MDA (MD = -2.35, 95% CI: -4.47 to -0.24, = 0.03, three studies). These improvements were statistically significant. Meanwhile, there was no significant improvement in SBP (MD = -4.82, 95% CI: -9.98 to 0.35, = 0.07, six studies), TG (MD = 1.28, 95% CI: -3.75 to 6.30, = 0.62, eight studies), IL-6 (MD = -1.5, 95% CI: -3.97 to 0.97, = 0.23, two studies), or hsCRP (MD = -1.10, 95% CI: -4.35 to 2.16, < 0.51, two studies). FBS, SBP, HDL-C, IL-6, CRP, hsCRP, and MDA had a relatively high heterogeneity.
CONCLUSION
Curcumin exhibited promising potential in enhancing markers associated with metabolic syndrome, including inflammation. However, additional studies are required to confirm such findings since the included evidence is limited and has a relatively high heterogeneity.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero, identifier CRD42022362553.
Topics: Randomized Controlled Trials as Topic; Curcumin; Dietary Supplements; Metabolic Syndrome; Oxidative Stress; Polyphenols; Inflammation; Humans; Curcuma
PubMed: 37522129
DOI: 10.3389/fendo.2023.1216708 -
Foods (Basel, Switzerland) Nov 2020This systematic review aimed to collect data and analyze the possible use of grape pomace, a winemaking industry byproduct, in the production of fortified foods. The... (Review)
Review
This systematic review aimed to collect data and analyze the possible use of grape pomace, a winemaking industry byproduct, in the production of fortified foods. The English articles found in Web of Science, Scopus, and Google Scholar, from January 2006 until May 2020, were used for the conduction of overview tables and meta-analysis. The systematic review emphasized the two main issues concerning grape pomace application to other food products: (i) grape pomace contains high amounts of health promoting compounds; and (ii) the use of grape pomace is influencing the waste management. The grape pomace has been used in the fortification of plant origin food, meat, fish, and dairy products, mainly due to higher polyphenols and dietary fiber contents. The fortification was declared as successful in all studied food types. The change of color, caused by polyphenolic compounds, was mainly observed as an adverse effect of the fortification. Higher levels of fortification also caused notable undesirable changes in texture. The most valuable influence of the grape pomace addition according to included papers and meta-analysis is certainly a higher nutritional quality and oxidative stability of fortified products, reflected as higher polyphenol and total dietary fiber content.
PubMed: 33171832
DOI: 10.3390/foods9111627 -
International Journal of Clinical... Oct 2021Curcumin is a natural polyphenol and the main compound from the rhizome of Turmeric (Curcuma longa) and other Curcuma species. It has been widely used for different... (Review)
Review
BACKGROUND
Curcumin is a natural polyphenol and the main compound from the rhizome of Turmeric (Curcuma longa) and other Curcuma species. It has been widely used for different medical purposes, such as improvement of pain and inflammatory conditions in various diseases.
PURPOSE
This systematic review was aimed to assess all studies regarding the efficacy of the pure form of curcumin (unformulated curcumin) on rheumatoid arthritis (RA).
METHODS
The comprehensive search of the literature was done until September 2020 on the MEDLINE, Embase, Scopus and Web of Knowledge databases. Out of 2079 initial records, 51 articles (13 in vitro and 37 animal and one human) were met our inclusion criteria.
RESULTS
Most studies have shown the curative effects of curcumin on clinical and inflammatory parameters of RA and reported different mechanisms; inhibition of mitogen-activated protein kinase family, extracellular signal-regulated protein kinase, activator protein-1 and nuclear factor kappa B are the main mechanisms associated with the anti-inflammatory function of curcumin in RA. The results of the only human study showed that curcumin significantly improved morning stiffness, walking time and joint swelling.
CONCLUSION
In conclusion, curcumin seems to be useful, and it is recommended that more human studies be performed to approve the cellular and animal results and determine the effective and optimal doses of curcumin on RA patients.
Topics: Animals; Anti-Inflammatory Agents; Arthritis, Rheumatoid; Curcumin; Humans; NF-kappa B
PubMed: 33914984
DOI: 10.1111/ijcp.14280 -
Current Hypertension Reports Jul 2023Accumulating data on the consumption of plant-based diets and their impact on blood pressure indicate a consensus that plant-based diets are linked to reduced blood... (Review)
Review
PURPOSE OF REVIEW
Accumulating data on the consumption of plant-based diets and their impact on blood pressure indicate a consensus that plant-based diets are linked to reduced blood pressure. The suggested mechanisms of action are manifold, and, in this systematic review, we provide a summary of the most recent findings on plant-based diets and their impact on blood pressure, along with an analysis of the molecules accountable for the observed effects.
RECENT FINDINGS
The overwhelming majority of intervention studies demonstrate that plant-based diets result in lower blood pressure readings when compared to diets that are based on animal products. The various mechanisms of action are being clarified. The data discussed in this systematic review allow us to conclude that plant-based diets are associated with lower blood pressure and overall better health outcomes (namely, on the cardiovascular system) when compared to animal-based diets. The mechanisms of action are being actively investigated and involve many macro- and micronutrients plentiful in plants and the dishes prepared with them.
Topics: Animals; Humans; Blood Pressure; Hypertension; Diet; Cardiovascular System; Diet, Vegetarian
PubMed: 37178356
DOI: 10.1007/s11906-023-01243-7 -
Advances in Nutrition (Bethesda, Md.) Jan 2024The high concentration of omega-3 polyunsaturated fats, dietary fibers, vitamins, minerals, and polyphenols found in nuts suggest their regular consumption may be a... (Meta-Analysis)
Meta-Analysis Review
The high concentration of omega-3 polyunsaturated fats, dietary fibers, vitamins, minerals, and polyphenols found in nuts suggest their regular consumption may be a simple strategy for improving reproductive health. This systematic review and meta-analysis aimed to present up-to-date evidence regarding the association between nut intake and fertility outcomes in males and females. Ovid MEDLINE, Embase, CINAHL, and Scopus were searched from inception to 30 June 2023. Eligible articles were interventional or observational studies in human subjects of reproductive age (18-49 y) that assessed the effects (or association) of dietary nut consumption (for a minimum of 3 mo) on fertility-related outcomes. Random-effects meta-analyses were completed to produce a pooled effect estimate of nut consumption on sperm total motility, vitality, morphology, and concentration in healthy males. Four studies involving 875 participants (646 males, 229 females) were included in this review. Meta-analysis of 2 RCTs involving 223 healthy males indicated consumption of ≥ 60g nuts/d increased sperm motility, vitality, and morphology in comparison to controls but had no effect on sperm concentration. Nonrandomized studies reported no association between dietary nut intake and conventional sperm parameters in males, embryo implantation, clinical pregnancy or live birth in males and females undergoing ART. Our meta-analysis shows that including at least 2 servings of nuts daily as part of a Western-style diet in healthy males improves sperm parameters, which are predictors of male fertility. Due to their nutritional profile, nuts were found to have potential to promote successful reproductive outcomes. This trial was registered at PROSPERO (CRD42020204586).
Topics: Female; Humans; Male; Pregnancy; Diet, Western; Fertility; Nuts; Seeds; Sperm Motility; Adolescent; Young Adult; Adult; Middle Aged
PubMed: 37977328
DOI: 10.1016/j.advnut.2023.100153 -
Medicina (Kaunas, Lithuania) Sep 2021Coffee is rich in phenolic acids, such as caffeic acid and chlorogenic acid (CGA). Polyphenol-rich diets were shown to reduce the risk of metabolic syndrome (MeTS). :... (Meta-Analysis)
Meta-Analysis Review
Effects of Caffeinated and Decaffeinated Coffee Consumption on Metabolic Syndrome Parameters: A Systematic Review and Meta-Analysis of Data from Randomised Controlled Trials.
Coffee is rich in phenolic acids, such as caffeic acid and chlorogenic acid (CGA). Polyphenol-rich diets were shown to reduce the risk of metabolic syndrome (MeTS). : This systematic review and meta-analysis discusses the effects of coffee consumption and its dose-response on MeTS parameters. : PubMed and Scopus were searched for relevant articles published between 2015 and 2020. This review focused on randomised controlled trials (RCTs) investigating the effect of coffee consumption on anthropometric measurements, glycaemic indices, lipid profiles, and blood pressure. Data from relevant studies were extracted and analysed using random, fixed, or pooled effects models with 95% confidence intervals (CIs). : Green coffee extract (GCE) supplementation (180 to 376 mg) was found to reduce waist circumference (weighted mean difference (WMD) = -0.39; 95% CI: -0.68, -0.10), triglyceride levels (WMD = -0.27; 95% CI: -0.43, -0.10), high-density lipoprotein-cholesterol levels (WMD = 0.62; 95% CI: 0.34, 0.90), systolic blood pressure (WMD = -0.44; 95% CI: -0.57, -0.32), and diastolic blood pressure (WMD = -0.83; 95% CI: -1.40, -0.26). Decaffeinated coffee (510.6 mg) reduced fasting blood glucose levels (WMD = -0.81; 95% CI: -1.65, 0.03). The meta-analysis showed that the intake of GCE containing 180 to 376 mg of CGA (administered in a capsule) and liquid decaffeinated coffee containing 510.6 mg of CGA improved the MeTS outcomes in study participants. : The findings of the review suggested that the effect of coffee on MeTS parameters varies depending on the types and doses of coffee administered. A more detailed RCT on specific coffee doses (with adjustment for energy and polyphenol intake) and physical activity is needed to further confirm the observed outcomes.
Topics: Coffee; Humans; Lipids; Metabolic Syndrome; Plant Extracts; Randomized Controlled Trials as Topic; Waist Circumference
PubMed: 34577880
DOI: 10.3390/medicina57090957 -
Antioxidants (Basel, Switzerland) May 2019Dietary polyphenols, including flavonoids, have been the focus of major recent attentions due to their wide content in a variety of foods commonly consumed and the... (Review)
Review
BACKGROUND
Dietary polyphenols, including flavonoids, have been the focus of major recent attentions due to their wide content in a variety of foods commonly consumed and the findings from numerous studies showing evidence of an association with positive outcomes on human health.
METHODS
A systematic search using electronic databases PubMed and EMBASE was performed to retrieve English language studies published from the earliest indexing year of each database to April 2019, reporting on the association between dietary flavonoids intake and hypertension.
RESULTS
The search strategy resulted in the final selection of 20 studies including 15 cross-sectional investigations and 7 prospective cohorts (1 study reported on 3 prospective cohorts). 5 prospective cohorts, comprising 200,256 individuals and 45,732 cases of hypertension were included in the quantitative analysis. Analysis by extreme quantiles of intake of flavonoid showed a non-significant association with decreased risk of hypertension (RR (risk ratio): 0.96, 95% CI (confidence interval): 0.89, 1.03). Taking into consideration individual flavonoid subclasses, dietary anthocyanins intake was associated with 8% reduction in risk of hypertension, when comparing highest vs. lowest exposure (RR: 0.92, 95% CI: 0.88, 0.97).
CONCLUSIONS
Further studies are needed to strengthen the retrieved association between anthocyanins consumption and decreased risk of hypertension and clarify whether total flavonoids or rather individual subclasses may exert beneficial effects on blood pressure.
PubMed: 31159186
DOI: 10.3390/antiox8060152 -
European Journal of Clinical Nutrition May 2019Animal studies have demonstrated anti-diabetic properties of several food-derived polyphenols, but data in humans remains unclear. This study aimed to review and... (Meta-Analysis)
Meta-Analysis
Animal studies have demonstrated anti-diabetic properties of several food-derived polyphenols, but data in humans remains unclear. This study aimed to review and meta-analyse evidence concerning the effect of the intake of several polyphenol-rich foods on gestational diabetes (GDM) risk. A systematic literature search was conducted in PubMed, Web of Science and Embase databases for observational studies on the association between dietary intake of foods/diets rich in polyphenols and GDM risk. Inclusion criteria were original research articles with full texts published in peer-reviewed English language journals, which investigated foods within the top 100 richest dietary sources of polyphenols and reported odds ratio/relative risk with their corresponding 95% confidence intervals. The quality of included studies was assessed using the Newcastle-Ottawa Scale. The intake of polyphenol-rich foods and dietary patterns in relation to GDM were pooled with fixed- and random-effects models. In total, 12 (10 cohort, 1 cross-sectional and 1 case-control) studies were included for the final systematic review, comprising 124,959 participants and including 5,786 women with GDM. Five studies found a significant, inverse association between the intake of polyphenol-rich foods or Mediterranean diet and GDM, whereas five studies reported no association and two exhibited a positive association. Meta-analyses further showed that the risk of GDM was about halved amongst women with the highest score of Mediterranean diet compared to those with the lowest score. The results suggest that dietary patterns rich in polyphenols may reduce the risk of GDM despite inconclusive evidence for polyphenol-rich food groups.
Topics: Diabetes, Gestational; Diet, Mediterranean; Female; Food; Humans; Observational Studies as Topic; Polyphenols; Pregnancy; Risk Factors
PubMed: 29941912
DOI: 10.1038/s41430-018-0218-7 -
Critical Reviews in Food Science and... 2022This study aimed to review the literature on studies that evaluated resveratrol's effects supplementation on parameters of diabetes in humans. We conducted an online... (Meta-Analysis)
Meta-Analysis
This study aimed to review the literature on studies that evaluated resveratrol's effects supplementation on parameters of diabetes in humans. We conducted an online search in the following databases: Pubmed, Lilacs, Scielo, Scopus, Web of Science, Embase, and Cochrane. It included experimental studies that investigated the effects of resveratrol supplementation for diabetes treatment or prevention and its relationship with fasting blood glucose, insulin resistance, and glycated hemoglobin. Observational, non-human studies and non-randomized clinical trials were excluded. We conducted a meta-analysis to evaluate the effects of resveratrol supplementation on fasting blood glucose, insulin resistance, and glycated hemoglobin. Thirty studies were included in the review. Almost 60% demonstrated at least one significant effect of the resveratrol supplementation related to diabetes. In the meta-analysis, there was a significant effect on the reduction of insulin resistance [SMD: -0.34; CI 95%: -0.64, -0.04; = 0.01; I = 70%] and glycated hemoglobin [SMD: -0.64; CI 95%: -1.22, -0.07; = 0.01; I = 90%]. For fasting blood glucose, the results were significant only for individuals with diabetes [SMD: -0.85; CI 95%: -1.49, -0.21; = 0.01; I = 90%]. This systematic review with meta-analysis demonstrated that resveratrol supplementation has protective effects on diabetes parameters.
Topics: Blood Glucose; Diabetes Mellitus, Type 2; Dietary Supplements; Glycated Hemoglobin; Humans; Insulin Resistance; Resveratrol
PubMed: 33480264
DOI: 10.1080/10408398.2021.1875980 -
Molecules (Basel, Switzerland) Apr 2023This review article describes studies published over the past five years on the combination of polyphenols, which are the most studied in the field of anticancer effects... (Review)
Review
This review article describes studies published over the past five years on the combination of polyphenols, which are the most studied in the field of anticancer effects (curcumin, quercetin, resveratrol, epigallocatechin gallate, and apigenin) and chemotherapeutics such as cisplatin, 5-fluorouracil, oxaliplatin, paclitaxel, etc. According to WHO data, research has been limited to five cancers with the highest morbidity rate (lung, colorectal, liver, gastric, and breast cancer). A systematic review of articles published in the past five years (from January 2018 to January 2023) was carried out with the help of all Web of Science databases and the available base of clinical studies. Based on the preclinical studies presented in this review, polyphenols can enhance drug efficacy and reduce chemoresistance through different molecular mechanisms. Considering the large number of studies, curcumin could be a molecule in future chemotherapy cocktails. One of the main problems in clinical research is related to the limited bioavailability of most polyphenols. The design of a new co-delivery system for drugs and polyphenols is essential for future clinical research. Some polyphenols work in synergy with chemotherapeutic drugs, but some polyphenols can act antagonistically, so caution is always required.
Topics: Polyphenols; Curcumin; Resveratrol; Antioxidants; Drug Therapy, Combination
PubMed: 37175156
DOI: 10.3390/molecules28093746