Policosanol supplementation significantly improves blood pressure among adults: A systematic review and meta-analysis of randomized controlled trials

Background and AimsPolicosanol contains a mixture of concentrated primary aliphatic alcohols extracted from sugar cane wax and is recognized as a cholesterol-lowering drug but previous studies reported that it could be helpful for reducing blood pressure as well. We aimed to systematically review all randomized control trials (RCTs) evaluating the efficacy of policosanol supplementation for lowering high blood pressure.Methods and ResultsThe following databases were searched up to March 2019: PubMed, Scopus, ISI Web of Science and the Cochrane library. Eligible RCTs were included if they investigate the effects of policosanol supplementation on systolic (SBP) and diastolic (DBP) blood pressure. Pooled effect size was measured using random effect model (DerSimmonon method). A total of nineteen studies with twenty-four arms were considered. Pooled effect size showed that SBP (WMD: −3.423 mmHg, 95% CI: −5.315, −1.531; p < 0.001) and DBP (WMD: −1.468 mmHg 95% CI: −2.632, −0.304, p = 0.013). decrease significantly after policosanol supplementation with significant heterogeneity among included studies (I² = 78.5% and 78.9% for SBP and DBP respectively). All subgroups showed a significant effect of policosanol supplementation except patients with mixed dyslipidemia for SBP and DBP and overweight subjects for DBP.ConclusionPolicosanol could lower SBP and DBP significantly; future long term studies are required to confirm these findings in the general population.     

Effects of chromium supplementation on blood pressure,body mass index,liver function enzymes and malondialdehyde in patients with type 2 diabetes: A systematic review and dose-response meta-analysis of randomized controlled trials

BackgroundSeveral studies reported beneficial effects of chromium supplementation for management of type 2 diabetes mellitus (T2DM). The present study aimed to provide a systematic review and meta-analysis of randomized controlled trials (RCTs) examining the effects of chromium supplementation on blood pressure, body mass index (BMI), liver function enzymes and malondialdehyde (MDA) in patients with T2DM.MethodsPubMed, Scopus, and Embase were searched up to 15 November 2020 with no language and time restriction. RCTs that reported the effects of chromium supplementation on blood pressure, BMI, liver function enzymes and MDA in patients with T2DM were included. A random-effects model was used to compute weighted mean differences (WMDs) with 95 % confidence intervals (CIs). Between-study heterogeneity was assessed by Cochran's Q test and quantified by I² statistic.ResultsOf 3586 publications, 15 RCTs were included for the meta-analysis. Pooled effect sizes indicated that chromium significantly reduced diastolic blood pressure (DBP) (WMD): -2.36 mmHg, 95 % CI: −4.14, −0.60; P = 0.008), and MDA (WMD: −0.55 umol/l, 95 % CI: −0.96, −0.14; P = 0.008). However, chromium supplementation did not significantly affect BMI, systolic blood pressure (SBP), alanine aminotransferase (ALT), aspartate aminotransferase (AST). Meta-regression analysis did not show significant linear relationship between dose of chromium and change in BMI (p = 0.412), SBP (p = 0. 319), DBP (p = 0.102), ALT (p = 0.923), AST (p = 0.986) and MDA (p = 0.055).ConclusionThe present systematic review and meta-analysis shows that supplementation with chromium at dose of 200–1000 μg/day may reduce DBP and MDA in T2DM patients.     

Effects of Cynara scolymus L. on glycemic indices:A systematic review and meta-analysis of randomized clinical trials

ObjectivesCynara scolymus L. (common artichoke) and its products have been considered as potential phytotherapeutic agents for various conditions, such as cardiovascular, hepatic and gastric diseases, among others. Until now, the effects of artichoke and artichoke products administration on glycemic indices have not been sufficiently appraised. The present study evaluated the effects of artichoke and artichoke products administration on the glycemic indices.MethodsClinical trials were identified in the Cochrane Library, PubMed, Embase and Scopus databases; to infinity until 15 March 2020. Weighted mean differences (WMD) were pooled using a random-effects model. Heterogeneity, sensitivity analysis and publication bias were reported using standard methods.ResultsPooled analysis of nine Randomized controlled trials (RCTs), demonstrated that the administration of artichoke and artichoke products led to a significant reduced fasting blood sugar (FBS) (WMD: −5.28 mg/dl, 95 % CI: −8.95, −1.61; p = 0.005). However, other glycemic indeces including fasting insulin (WMD: −0.45 μIU/dL, 95 % CI: −1.14, 0.25; p = 0.20), HOMA-IR (MD: −0.25, 95 % CI: −0.57, 0.07; p = 0.12) or Hemoglobin A1c (HbA1c) (WMD: −0.09, 95 % CI: −0.20, 0.02; p = 0.09) did not alter after the administration of artichoke and artichoke products. A subgroup analysis comparing the kind of intervention, revealed that just the supplementation of artichoke and artichoke products, in a noco-supplementation form, was efficacy for the reduction of Homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: −0.52, 95 % CI: −0.85, −0.19; p = 0.002).ConclusionsThe supplementation of artichoke and artichoke products can significantly reduce the FBS concentrations in humans. Moreover, these outcomes suggested that just the supplementation of artichoke and artichoke products is more effective in the reduction of HOMA-IR levels than the co-supplementation form. However, additional clinical trials with longer study periods are necessitated to obtain a robust conclusion for producing new guidelines as part of a healthy diet.     

The effect of ginger supplementation on metabolic profiles in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials

BackgroundThere is some evidence regarding the positive effects of ginger supplementation on metabolic profile in patients with type 2 diabetes (T2DM). However, they are conflicting. The present systematic review and meta-analysis aimed to summarize earlier findings for the effect of ginger supplementation on metabolic profile in patients with T2DM.MethodsScopus, PubMed and Google Scholar databases were systematically searched up until September 2021 to collect all randomized clinical trials that evaluated the effect of ginger supplementation on FBS, HbA₁c, TC, TG, LDL, HDL, SBP and DBP in patients with T2DM. We conducted our study according to the 2020 PRISMA guidelines. We included only English language publications. Pooled effect sizes were measured using a random-effects model and were reported as the weighted mean difference (WMD) and 95% CI. In addition, the Cochrane Collaboration's risk of bias tool was used to evaluate quality of the trials.ResultsIn overall, 10 articles were included in this systematic review and meta-analysis. Our pooled meta-analysis indicated a significant reduction in FBS following ginger supplementation by polling 8 effect sizes [weighted mean difference (WMD): − 18.81; 95% CI: − 28.70, − 8.92), I² = 77.4%] and in HbA₁C through 7 effect sizes (WMD: −0.57; 95% CI: −0.93, −0.20, I² =88.6%). Pooling 5 effect sizes, we found a significant reduction in SBP (WMD: −4.20; 95% CI: −7.64, −0.77, I2 =97%) and DBP [WMD: − 1.61; 95% CI: − 3.04, − 0.18), I2 = 93.2%] after supplementation with ginger. However, our pooled meta-analysis indicated that ginger supplementation had no significant influence on lipid profile involving TG, TC, LDL and HDL.ConclusionsWe found significant reductions in FBS, HbA₁C, SBP and DBP after supplementation with ginger in patients with T2DM compared to control group, with no significant changes in serum lipids. Further large RCTs are required to shed light on this issue.     

The Effect of Lactobacillus Consumption on Human Blood Pressure: a Systematic Review and Meta-Analysis of Randomized Controlled Trials

ObjectivesPrevious clinical studies have shown controversial results regarding the effect of Lactobacillus supplementation on blood pressure (BP). The purpose of this systematic review and meta-analysis is to examine the effect of Lactobacillus consumption on BP.MethodsEligible randomized controlled trials (RCTs) were searched from five electronic databases until May 2020. In total, 18 studies were included in our meta-analysis. Quality of the selected studies was assessed, and a random-effects model was used to calculate the overall effect sizes of weighted mean differences (WMD). This systematic review was registered in PROSPERO with the number: CRD42019139294.ResultsLactobacillus consumption significantly reduced systolic blood pressure (SBP) by −2.74 mmHg (95% confidence interval, −4.96 to −0.51) and diastolic blood pressure (DBP) by −1.50 mmHg (95% confidence interval, −2.44 to −0.56) when comparing with the control group. Subgroup analysis showed that type 2 diabetes mellitus (T2DM) patients, Asian individuals, or borderline hypertension participants were more sensitive to daily consumption of Lactobacillus. And the effect of Lactobacillus on BP-reduction was more significant in capsule form, with the dose was above 5 × 10⁹ colony-forming unit (CFU)/day or lasted for more than 8 weeks.ConclusionsOur present study suggests that Lactobacillus consumption in capsule form when the daily dose is above 5 × 10⁹ CFU for more than 8 weeks can decrease SBP or DBP in T2DM patients, borderline hypertension participants or Asian individuals.     

The effects of supplementation with Cynara scolymus L. on anthropometric indices: А systematic review and dose-response meta-analysis of clinical trials

BackgroundStudies on the efficacy of artichoke administration on anthropometric indices gave different outcomes. Hence, a systematic review and dose-response meta-analysis were accomplished to understand the effects of artichoke administration on anthropometric indices.MethodsRelated clinical trials were found by searching in PubMed, Embase, the Cochrane Library and Scopus databases up to 29 February 2020. Weighted Mean Differences (WMD) were analyzed using a random-effects model. Heterogeneity, publication bias and sensitivity analysis were assessed for anthropometric indices.ResultsPooled analysis of 10 randomized controlled trials (RCTs) suggested that the artichoke administration has effect on waist circumference (WMD: -1.11 cm, 95 % CI: -2.08 to - 0.14), as opposed to the other anthropometric indices including weight (WMD: -0.62 kg, 95 % CI: -1.86 to 0.61) or BMI (WMD: -0.12, 95 % CI: -0.43 to 0.20). However, the analysis of the subgroups according to the health status showed that artichoke supplementation in hypertensive patients significantly reduced weight (WMD: -2.34 kg, 95 % CI: -3.11 to -1.57) but not the other indicators (WMD: -0.06 kg, 95 % CI: 0.78 to 0.67).ConclusionsThe artichoke supplementation has effect on the waist circumference, but not on the other anthropometric indices. For establishment of more accurate conclusion more studies with longer administration duration are need to be done.     

Soy intake is associated with lowering blood pressure in adults: A systematic review and meta-analysis of randomized double-blind placebo-controlled trials

BackgroundSoy has several beneficial effects on cardiovascular disease (CVD); however, results of clinical trial studies are equivocal. Thus, the present study sought to discern the efficacy of soy intake on blood pressure.MethodsThe search process was conducted in PubMed, Scopus, Web of Science, and Cochrane Library, to ascertain studies investigating the efficacy of soy intake on blood pressure in adults, published up to June 2020. A random-effects model was applied to pool mean difference and 95 % confidence interval (CI). Begg’s and Egger’s methods were conducted to assess publication bias.ResultsPooled effects from 17 effect sizes revealed a significant improvement in systolic blood pressure (SBP) (−1.70; −3.34 to −0.06 mmHg; I² = 45.4 %) and diastolic blood pressure (DBP) (−1.27; −2.36 to −0.19 mmHg, I² = 43.9 %) following soy consumption, in comparison with controls. Subgroup analysis demonstrated a reduction in both SBP and DBP in younger participants with lower baseline DBP and intervention durations of <16 weeks.ConclusionOur results suggest that soy intake is associated with an ameliorating effect on blood pressure in adults.     

The effects of regular consumption of green or black tea beverage on blood pressure in those with elevated blood pressure or hypertension: A systematic review and meta-analysis

ObjectiveAs a popular beverage, there has been much interest in studying the effects of tea intake on hypertension (HTN), a particular risk factor for cardiovascular disorders (CVDs). We have thus aimed to isolate the randomized controlled trials investigating the efficacy of black or green tea as a beverage in subjects with elevated blood pressure (BP), or HTN.MethodsPubMed, Scopus, Web of Science, and ProQuest dissertations and theses databases were searched from February 1, 1995, up to July 20, 2019, to identify relevant studies.ResultsThe search strategy generated 1119 trials, of which finally five trials fulfilled the criteria for being included in the current study. Three out of 5 articles showed a low risk of bias. According to nine measurements derived from 5 trials on 408 individuals, it was found that regular tea intake resulted in the reduction in SBP (weighted mean difference (WMD): −4.81 mmHg, 95 %CI: −8.40 to −1.58, P = .004) and DBP (WMD:-1.98 mmHg, 95 %CI: −3.77 to −0.20, P = .029); however, excluding the most heterogeneous trials showed that regular tea intake might reduce SBP and DBP by about −3.53 and −0.99 mmHg, respectively. Based on meta-regression findings, we found the longer the duration of tea intake (≥3months), the higher the decrease in both SBP and DBP. Categorized studies, according to the tea type, revealed that the hypotensive effects of green tea were more pronounced compared to black tea. None of the studies reported any side effects.ConclusionThese results suggest the positive effects of regular tea intake on BP in subjects with elevated BP or HTN. Hence, it may be applicable to physicians, health care providers, and particularly HTN patients.     

The effects of carnitine supplementation on clinical characteristics of patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis of randomized controlled trials

ObjectiveThe beneficial effects of carnitine supplementation on nonalcoholic fatty liver disease are unclear. We conducted a systematic review and meta-analysis to evaluate the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance in patients with nonalcoholic fatty liver disease.MethodsA comprehensive search of PubMed, Web of Science, Scopus, Cochrane Library, and Google Scholar databases were performed. Only randomized placebo-controlled human studies that examined the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance up to September 2019 were included. Fixed effects or random-effects models were applied to compute the pooled effect size. Heterogeneity assessments were performed using Cochran’s Q test and I-squared statistics. The quality of the studies was assessed using the Jaded scale.ResultsA total of 5 articles were selected, including 334 individuals (167 in control and 167 in intervention groups). The results demonstrated that carnitine supplementation significantly reduced homeostasis model assessment of insulin resistance (HOMA-IR) (WMD: −0.91; 95 % CI: −1.11, −0.72; p < 0.001, I² = 0.0 %) and the levels of aspartate aminotransferase (AST) (WMD: −16.62; 95 % CI: −28.11, −5.14; IU/l; p = 0.005, I² = 93.5 %), alanine aminotransferase (ALT) (WMD: -33.39; 95 % CI: −45.13, −21.66; IU/l; p < 0.001, I² = 93.4 %), and triglycerides (TG) (WMD: −22.13; 95 % CI: −38.91, −5.34; mg/dl; p = 0.01; I² = 0.0 %). However, the results of the pooled effect size did not show any significant effect of carnitine supplementation on body mass index (BMI) (WMD: 0.07; 95 % CI: −0.15, 0.29; p = 0.55; I² = 0.0 %), body weight (WMD: −0.28; 95 % CI: −2.23, 1.68; p = 0.78; I² = 45.7 %), the levels of gamma-glutamyl transferase (γGT) (WMD: −11.31; 95 % CI: −24.35, 1.73; IU/l; p = 0.09, I² = 61.1 %), cholesterol (WMD: −13.58; 95 % CI: −46.77, 19.60; mg/dl; p = 0.42; I² = 94.9 %), high-density lipoprotein-cholesterol (HDL-C) (WMD: 1.36; 95 % CI: −0.96, 3.68; mg/dl; p = 0.25; I² = 64.7 %), and low density lipoprotein-cholesterol (LDL-C) (WMD: −14.85; 95 % CI: −45.43, 15.73; mg/dl; p = 0.34; I² = 96.4 %).ConclusionsThis analysis shows that carnitine supplementation for patients with nonalcoholic fatty liver disease demonstrates a reduction in AST, ALT, TG levels and HOMA-IR. However, no significant effect of carnitine supplementation was observed on BMI, body weight, the levels of γGT, TC, HDL-cholesterol and LDL-cholesterol.     

The effect of almond intake on blood pressure: A systematic review and meta-analysis of randomized controlled trials

ObjectiveThe present systematic review and meta-analysis aimed determine the efficacy of almond intake on blood pressure (BP).MethodsPubMed, Scopus, ISI Web of Science, Cochrane library and Google Scholar were comprehensively searched to infinity until December 2019. Randomized clinical trials (RCTs) reporting effects of almond intake on aortic and brachial BP were included. Weighted mean differences (WMDs) were pooled using a random-effects model. Standard methods were used for assessment of heterogeneity, sensitivity analysis, and publication bias.ResultsA total of 16 RCTs (1128 participants) were included in the meta-analysis. Pooled analysis suggested that almond intake can reduced diastolic BP (DBP) (WMD = -1.30 mmHg; 95 % CI: -2.31,-0.30, p = 0.01, I² = 0.0 %). However, there was not any impact of almond intake on systolic BP (SBP) (WMD = -0.83 mmHg; 95 % CI: -2.55, 0.89, p = 0.34, I² = 58.9 %). Subgroup analysis revealed a significant reduction in SBP levels in subjects with lower SBP and lower dose of almonds.ConclusionWe found that almonds might have a considerable favorite effect in BP and especially in DBP, and it could be encouraged as part of a healthy diet; however due to the high calorie content, the intake should be part of healthy diet.     

The effect of barberry (Berberis vulgaris L.) supplementation on blood pressure: A systematic review and meta-analysis of the randomized controlled trials

ObjectiveWe identified and quantified the results of randomized clinical trials by examining the effect of barberry supplementation on blood pressure.MethodsWe conducted a comprehensive search in the medical bibliographic database up to May 2020 on randomized clinical trials investigating the effect of barberry supplementation on adult blood pressure. Intensive literature searches and data extraction according to a prefixed scheme was performed independently by two investigators.ResultsThrough 5 randomized clinical trial studies, 350 subjects with 175 cases for the intervention group and 175 cases for control group were included in our study. The intervention period ranged from 4 to 12 weeks. In general, barberry supplementation did not have a significant effect on systolic blood pressure (WMD: -4.15 mmHg; 95 % CI: -10.3, 1.99, P = 0.185) and diastolic blood pressure (WMD: -1.22 mmHg; 95 % CI: -6.26, 3.82, P = 0.635). Our study was heterogeneous and subgroup analysis did not eliminate heterogeneity.ConclusionTotally, based on this study, we cannot conclude that barberry supplementation has beneficial effects on blood pressure. Also, all included studies had limitations such as different in geographical situations, Dietary of participants, health conditions, and pharmacological forms of berberis. Therefore, further study in this area is recommended.     

The effect of Saffron supplementation on waist circumference,HA1C,and glucose metabolism: A systematic review and meta-analysis of randomized clinical trials

ObjectiveCarotenoids (including zeaxanthin and lycopene) and phytosterols reportedly confer beneficial effects on metabolic profile and function, which is of clinical importance. Thus, we sought to review the saffron effects on waist circumstance (WC), fasting plasma glucose (FPG), and HA1C concentrations reported in Randomized Control Trials (RCTs).MethodA comprehensive systematic electronic search was performed in PubMed/MEDLINE, Embase, Google Scholar, Cochrane, Web of sciences, and SCOPUS to identify RCTs up to February 2019 without any language restrictions. The pooled weighted mean difference (WMD) calculated with DerSimonian-Laird random. PRISMA guidelines adhered to for this meta-analysis.ResultNine articles with 12 arms containing 595 participants were included in this study. Our study found WC was significantly reduced (WMD: −2.18 cm, 95 % CI: −4.05, −0.32) and FPG (WMD: −6.54 mg/dl, 95 % CI: −10.22, −2.85) following saffron intervention. Subgroup analysis highlighted that FPG levels (WMD: −10.24 mg/dl, 95 % CI: −15.76, −4.72) reduced significantly when intervention duration was longer than twelve weeks. There was no significant effect on HA1C levels (WMD: −0.13 mg/dl, 95 % CI: −0.31, 0.04) following saffron intervention.ConclusionIn conclusion, the present study indicates beneficial effects on WC and FPG, following saffron supplementation.     

The effects of pomegranate supplementation on biomarkers of inflammation and endothelial dysfunction: A meta-analysis and systematic review

ObjectsCardiovascular disease (CVD) is one of the leading causes of death worldwide. CVD is associated with increased levels of reactive oxygen species which are pro-inflammatory and can damage the endothelium. The pomegranate fruit is a rich source of phytochemicals with a high antioxidant and anti-inflammatory activity, possessing thus health benefits. This systematic review and meta-analysis aims to evaluate the effect of pomegranate juice on the biomarkers of inflammation and vascular dysfunction.MethodsStudies were identified using the PubMed/Medline and SCOPUS databases. Screening of relevant articles and references was carried out from inception until May 2019. This systematic review and meta-analysis was performed using the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines.ResultsOverall, 16 randomized controlled trials (RCTs) involving 572 subjects were included in this study. Combining effect sizes from 16 studies, we recorded that pomegranate supplementation significantly reduced hs-CRP, IL-6 and TNF-α (Weighted Mean Diff ;erences (WMD): −6.57 mg/L, 95 % CI: −10.04 to −3.10, P = 0.000; WMD: −1.68 pg/mL, 95 % CI: −3.52, 0.157, P = 0.000; WMD: −2.37 pg/mL, 95 % CI: −3.67, −1.07, P = 0.00, respectively) levels, when compared to placebo. No significant reduction was found in CRP (WMD: 2.19 mg/dL, 95 % CI: −3.28, 7.67, P = 0.61), E-selectin (WMD: 8.42 ng/mL, 95 % CI: −22.9, 39.8, P = 0.599), ICAM (WMD= −17.38 ng/mL, 95 % CI: −53.43, 18.66, P = 0.107), VCAM (WMD: −69.32 ng/mL, 95 % CI: −229.26, 90.61, P = 0.396) or MDA (WMD: 0.031 μmol/L, 95 % CI: −1.56, 0.218, P = 0.746) comparing pomegranate supplementation to placebo.ConclusionWe found a significant effect of pomegranate supplementation on hs-CRP, IL-6 and TNF-α in adults. However, the effects of pomegranate supplementation on CRP, E-selectin, ICAM, VCAM or MDA were not significant in this meta-analysis.     

Effects of curcumin/turmeric supplementation on lipid profile: A GRADE-assessed systematic review and dose–response meta-analysis of randomized controlled trials

IntroductionNumerous approaches have been assigned to treat dyslipidemia (DLP). Turmeric/curcumin have been widely investigated with this regard. In the current study, we explored the effect of curcumin/turmeric supplementation on lipid profile.MethodsOnline databases were searched up to October 2022. The outcomes included triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), apolipoprotein B (Apo-B), and apolipoprotein A (Apo-A). We used the Cochrane quality assessment tool to evaluate the risk of bias. The effect sizes were estimated as weighted mean difference (WMD) and 95% confidence intervals (CIs).ResultsOut of 4182 articles retrieved from the initial search, 64 randomized clinical trials (RCTs) were included in the study. Between-study heterogeneity was significant. Meta-analysis showed that turmeric/curcumin supplementation exerts statistically significant improvements on blood levels of TC (WMD = −3.99 mg/dL; 95% CI = −5.33, −2.65), TG (WMD = −6.69 mg/dL; 95% CI = −7.93, −5.45), LDL-c (WMD = −4.89 mg/dL; 95% CI = −5.92, −3.87), and HDL-c (WMD = 1.80 mg/dL; 95% CI = 1.43, 2.17). However, turmeric/curcumin supplementation was not associated with improvements in blood levels of Apo-A or Apo-B. The studies did not thoroughly address the issues of potency, purity, or consumption with other foods.ConclusionTurmeric/curcumin supplementation seems to be effective in improving blood levels of TC, TG, LDL-c, and HDL-c; but may not be capable of improving their pertinent apolipoproteins. Since the evidence was assessed to be low and very low concerning the outcomes, these findings should be dealt with caution.     

Impact of Cinnamon Supplementation on cardiometabolic Biomarkers of Inflammation and Oxidative Stress: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background & objectiveTo date, cinnamon supplementation has been investigated due to its antioxidant and anti-inflammatory properties. Several studies have confirmed the effects of cinnamon supplementation on several markers of cardiometabolic health. However, the effects of cinnamon supplementation on inflammation and oxidative stress levels warrant further investigation. Hence, the current meta-analysis was conducted to elucidate the impact of cinnamon supplementation on biomarkers of inflammation and oxidative stress.MethodsTo perform this systematic review and meta-analysis, we employed the Preferred Reporting Items of Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The systematic search of available clinical trials was performed using the following databases: PubMed/MEDLINE, Scopus, Cochrane Library, Web of Science, Embase, and Google Scholar, up to January 2020.ResultsAfter removing the duplicates, 1145 studies were eligible for analysis and 12 of them were included in the meta-analysis. The dose of cinnamon powder investigated in the included trials ranged from 1.5 to 4 g/day. Cinnamon supplementation resulted in a significant reduction of C-reactive protein (CRP) (weight mean difference (WMD): −2.22 mg/L, 95 % CI: −3.74, −0.69, P = 0.004) and malondialdehyde (MDA) (WMD: −0.79 mmol/L, 95 % CI: −1.28, −0.29, P = 0.002), and marginally statistical significant decrease in interleukin-6 (IL-6) (WMD: −1.48 pg/mL, 95 % CI: −2.96, −0.01, P = 0.049). Moreover, it was associated with an increase in the total antioxidant capacity (TAC) (WMD: 0.34 mmol/L, 95 % CI: 0.04, 0.64, P = 0.026). However, the levels of intercellular adhesion molecule-1 (ICAM-1) (WMD: 1.53 ng/mL, 95 % CI: −12.03, 15.10, P = 0.82) did not change significantly following cinnamon supplementation.ConclusionsCinnamon supplementation may be an adjuvant for reducing inflammation and oxidative stress levels in humans.     

Effects of green coffee bean extract on C-reactive protein levels: A systematic review and meta-analysis of randomized controlled trials

Background & objective: The effects of green coffee bean extract (GCBE) supplementation on inflammatory biomarkers have been widely spread. The purpose of this article was to assess the impact of GCBE supplementation on C-reactive protein (CRP) levels.MethodsThe literature search was performed in four databases (Scopus, PubMed, the Cochrane Library, and Google Scholar) to identify studies that examined the influence of GCBE supplementation on CRP levels up to August 2019. Mean and standard deviation (SD) of the outcomes were used to estimate the weight mean difference (WMD) between intervention and control groups for the follow-up period.ResultsFive (5) studies, with 6 arms, reported CRP as an outcome. Statistically, the use of GCBE supplements resulted in a significant change in CRP levels (WMD: −0.017 mg/dL, 95 % CI: −0.032, −0.003, p = 0.018), whose overall findings were obtained from random-effects model. In addition, a significantly greater reduction in CRP was noted for studies with doses of GCBE supplements ≥ 1000 mg/d (WMD: −0.015 mg/dL, 95 % CI: −0.020, −0.010, p < 0.000), length of intervention < 4 weeks (WMD: -0.015 mg/dL, 95 % CI: −0.020, −0.010, p < 0.001), and for non-healthy subjects (WMD: −0.019 mg/dL, 95 % CI: −0.027, −0.011, p < 0.001). Dyslipidemia, hypertension and non-alcoholic fatty liver disease were the ailments of the studies that encompassed non-healthy patients.ConclusionsThis meta-analysis shows that the use of GCBE supplements resulted in a statistical decrease in CRP levels, mainly for non-healthy subjects. However, due to the limited number of studies, further randomized clinical trials are crucial in this regard.     

The effects of cashew nut intake on lipid profile and blood pressure: A systematic review and meta-analysis of randomized controlled trials

BackgroundDyslipidemia and hypertension are important risk factors for cardiovascular disease (CVD). Some studies have suggested that the consumption of nuts may reduce CVD risk.ObjectiveThe present systematic review and meta-analysis was conducted to investigate the efficacy of cashew nut consumption on lipid profile and blood pressure.MethodsPubMed, Embase, Scopus, Web of Science and Cochrane Library were systematically searched to identify randomized control trials (RCTs) examining the effects of cashew nut intake on serum triglycerides (TG), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), serum total cholesterol (TC), systolic blood pressure (SBP) or diastolic blood pressure (DBP) until 15 November 2019. A random-effects model was used to pool weighted mean difference (WMD) and 95 % confidence intervals (CI). Potential publication bias was assessed using Egger’s test. Sensitivity analysis was performed to assess the impact of each individual study on the pooled results.ResultsA meta-analysis on 392 participants showed that cashew nut consumption had no significant effects on lipid profile and DBP. However, there was a significant reduction in SBP (WMD = -3.39, 95 % CI = [-6.13, -0.65], P = 0.01, I² = 0.0 %) in the group receiving cashew nut compared to the controls. There was no significant publication bias in the meta-analysis. A sensitivity analysis showed that omitting each study did not change the significance of results.ConclusionThis meta-analysis demonstrated that cashew nut consumption might reduce SBP but has no effects on lipid profile and DBP.     

Isometric Exercise Training for Blood Pressure Management: A Systematic Review and Meta-analysis

ObjectiveTo conduct a systematic review and meta-analysis quantifying the effects of isometric resistance training on the change in systolic blood pressure(SBP), diastolic blood pressure (DBP), and mean arterial pressure in subclinical populations and to examine whether the magnitude of change in SBP and DBP was different with respect to blood pressure classification.Patients and MethodsWe conducted a systematic review and meta-analysis of randomized controlled trials lasting 4 or more weeks that investigated the effects of isometric exercise on blood pressure in healthy adults (aged ≥18 years) and were published in a peer-reviewed journal. PubMed, CINAHL, and the Cochrane Central Register of Controlled Trials were searched for trials reported between January 1, 1966, and July 31, 2013. We included 9 randomized trials, 6 of which studied normotensive participants and 3 that studied hypertensive patients, that included a total of 223 participants (127 who underwent exercise training and 96 controls).ResultsThe following reductions were observed after isometric exercise training: SBP—mean difference (MD), −6.77 mm Hg (95% CI, −7.93 to −5.62 mm Hg; P<.001); DBP—MD, −3.96 mm Hg (95% CI, −4.80 to −3.12 mm Hg; P<.001); and mean arterial pressure—MD, −3.94 mm Hg (95% CI, −4.73 to −3.16 mm Hg; P<.001). A slight reduction in resting heart rate was also observed (MD, −0.79 beats/min; 95% CI, −1.23 to −0.36 beats/min; P=.003).ConclusionIsometric resistance training lowers SBP, DBP, and mean arterial pressure. The magnitude of effect is larger than that previously reported in dynamic aerobic or resistance training. Our data suggest that this form of training has the potential to produce significant and clinically meaningful blood pressure reductions and could serve as an adjunctive exercise modality.     

Valsartan vs. other angiotensin II receptor blockers in the treatment of hypertension: a meta‐analytical approach

Objective: To compare the efficacy of valsartan in systolic (SBP) and diastolic blood pressure (DBP) reduction with other angiotensin II receptor blockers (ARBs) in essential hypertension. Methods: Systematic literature search of databases between October 1997 and May 2008. Meta‐analysis of short‐term, double‐blind, parallel group, randomised controlled trials (RCTs) for treatment of adult hypertension (DBP: 90–115 mmHg). Random‐effects meta‐regression adjusting for baseline blood pressure (BP) was used to analyse the data. Mean change in SBP and DBP was estimated for each individual drug and dose combination. Results: In all, 31 RCTs (n = 13,110 patients) were included in the analysis. Six studies include trial arms with candesartan, six irbesartan, 13 losartan, two olmesartan, five telmisartan and 12 valsartan. The weighted average reduction in mean SBP and DBP for valsartan 160 mg was ?15.32 mmHg (95% CI: ?17.09, ?13.63) and ?11.3 mmHg (95% CI: ?12.15, ?10.52) and for 320 mg was ?15.85 mmHg (95% CI: ?17.60, ?14.12) and ?11.97 mmHg (95% CI: ?12.81, ?11.16); these are statistically significantly greater reductions compared with losartan 100 mg, which was ?12.01 mmHg (95% CI: ?13.78, ?10.25) and ?9.37 mmHg (95% CI: ?10.18, ?8.54) for SBP and DBP respectively. There is evidence that valsartan 160 mg reduces SBP and DBP more than irbesartan 150 mg and reduced DBP more than candesartan 16 mg. No other statistically significant difference in efficacy is demonstrated. Conclusion: Valsartan administered at 160 or 320 mg is more effective at lowering BP than losartan 100 mg and shows comparable efficacy to other ARBs in patients with essential hypertension.