The effects of curcumin‐containing supplements on biomarkers of inflammation and oxidative stress: A systematic review and meta‐analysis of randomized controlled trials

Besides other benefits, curcumin is getting more recognized for its antioxidant and anti‐inflammatory properties, highlighting the importance of curcumin application for chronic disease prevention. This systematic review and meta‐analysis of randomized controlled trials (RCTs) was conducted to assess the influence of curcumin‐containing supplements on biomarkers of inflammation and oxidative stress. MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials were searched till January 2018 for eligible studies. The selected studies were evaluated for their quality using the Cochrane risk of bias tool and relevant data were extracted from included studies. Data were pooled using the inverse variance method and expressed as standardized mean difference (SMD) with 95% confidence intervals (95% CI). Fifteen RCTs were included in the final analysis. The meta‐analysis indicated that curcumin supplementation significantly decreased interleukin 6 (IL‐6) (SMD ?2.08; 95% CI [?3.90, ?0.25]; p = 0.02), high‐sensitivity C‐reactive protein (hs‐CRP) (SMD ?0.65; 95% CI [?1.20, ?0.10], p = 0.02), and malondialdehyde (MDA) concentrations (SMD ?3.14; 95% CI [‐4.76, ?1.53], p < 0.001). Though, curcumin supplementation had no significant effect on tumor necrosis factor‐alpha (SMD ?1.62; 95% CI [?3.60, 0.36]; p = 0.10) and superoxide dismutase levels (SMD 0.34; 95% CI [?1.06, 1.74], p = 0.63). Overall, this meta‐analysis suggests that taking curcumin‐containing supplements may exert anti‐inflammatory and antioxidant properties through a significant reduction in IL‐6, hs‐CRP, and MDA levels.     

Effects of saffron (Crocus sativus L.) supplementation on inflammatory biomarkers: A systematic review and meta‐analysis

The effect of saffron supplementation on subclinical inflammation remains inconclusive. We performed a systematic review and meta‐analysis to summarize available findings on the effect of saffron supplementation on inflammatory biomarkers (C‐reactive protein [CRP], tumor necrosis factor‐α [TNF‐α], and interleukin‐6 [IL‐6]) in adults. We searched PubMed/Medline, Scopus, Web of Science, and Google Scholar databases up to November 2019 using relevant keywords to identify eligible trials. All randomized controlled trials (RCTs) that examined the effect of oral saffron supplementation on plasma concentrations of CRP, TNF‐α, and IL‐6 were included. For each outcome, mean differences and SDs were pooled using a random‐effects model. Overall, eight RCTs were included in this meta‐analysis. The pooled results showed that saffron supplementation did not result in significant changes in serum CRP (weighted mean difference [WMD]: ?0.43 mg/L; 95% confidence interval [CI]: ?1.04 to 0.17; p = .16), serum TNF‐α (WMD: ?1.29 pg/mL; 95% CI: ?4.13 to 1.55; p = .37), and IL‐6 concentrations (WMD: 0.11 pg/mL; 95% CI: ?0.79 to 1.00; p = .81). Subgroup analysis indicated a significant reduction in serum CRP levels in studies with baseline CRP of ≥3 mg/L, saffron dosage of ≤30 mg/day, and intervention duration of <12 weeks, as well as trials that used crocin. Similarly, saffron was found to decrease TNF‐α in studies that recruited non‐diabetic subjects, subjects with baseline levels of ≥15 pg/mL, and participants with <50 years old, as well as trials that administered saffron at the dosage of ≤30 mg/day. We also found a significant non‐linear effect of saffron dosage on serum CRP concentrations (p_{non‐linearity} = .03). The overall results indicated that saffron supplementation did not affect inflammatory cytokines. Further high‐quality studies are needed to firmly establish the clinical efficacy of supplemental saffron on inflammatory biomarkers.     

The effects of grape seed extract on glycemic control,serum lipoproteins,inflammation, and body weight: A systematic review and meta‐analysis of randomized controlled trials

The aim of this systematic review and meta‐analysis was to analyze the effects of grape seed extract (GSE) on glycemic control and serum lipoproteins, inflammation and body weight. Two independent authors systematically searched online databases including EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until May 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of included trials. The heterogeneity among the included studies was assessed using Cochrane's Q test and I‐square (I²) statistic. Data were pooled using a random‐effects model and weighted mean difference (WMD) was considered as the overall effect size. Fifty trials were included in this meta‐analysis. Pooling effect sizes from studies demonstrated a significant decrease in fasting plasma glucose (FPG) (WMD): ?2.01; 95% confidence interval (CI): ?3.14, ?0.86), total cholesterol (TC; WMD: ?6.03; 95% CI: ?9.71, ?2.35), low‐density lipoprotein (LDL) cholesterol (WMD: ?4.97; 95% CI: ?8.37, ?1.57), triglycerides (WMD: ?6.55; 95% CI: ?9.28, ?3.83), and C‐reactive protein (CRP) concentrations (WMD: ?0.81; 95% CI: ?1.25, ?0.38) following GSE therapy. Grape seed did not influence HbA1c, HDL cholesterol levels, and anthropometric measurements. This meta‐analysis demonstrated that GSE intake significantly reduced FPG, TC, LDL cholesterol, triglycerides, and CRP levels.     

Effects of quercetin supplementation on glycemic control among patients with metabolic syndrome and related disorders: A systematic review and meta‐analysis of randomized controlled trials

This systematic review and meta‐analysis of randomized controlled trials was performed to determine the effect of quercetin supplementation on glycemic control among patients with metabolic syndrome and related disorders. Databases including PubMed, MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials were searched until August 30, 2018. Nine studies with 10 effect sizes out of 357 selected reports were identified eligible to be included in current meta‐analysis. The pooled findings indicated that quercetin supplementation did not affect fasting plasma glucose (FPG), homeostasis model of assessment‐estimated insulin resistance, and hemoglobin A1c levels. In subgroup analysis, quercetin supplementation significantly reduced FPG in studies with a duration of ≥8 weeks (weighted mean difference [WMD]: ?0.94; 95% confidence interval [CI; ?1.81, ?0.07]) and used quercetin in dosages of ≥500 mg/day (WMD: ?1.08; 95% CI [?2.08, ?0.07]). In addition, subgroup analysis revealed a significant reduction in insulin concentrations following supplementation with quercetin in studies that enrolled individuals aged <45 years (WMD: ?1.36; 95% CI [?1.76, ?0.97]) and that used quercetin in dosages of ≥500 mg/day (WMD: ?1.57; 95% CI [?1.98, ?1.16]). In summary, subgroup analysis based on duration of ≥8 weeks and used quercetin in dosages of ≥500 mg/day significantly reduced FPG levels.     

Effects of ginseng supplementation on selected markers of inflammation: A systematic review and meta‐analysis

The present meta‐analysis was performed to evaluate the efficacy of ginseng administration on serum level of inflammatory biomarkers. We performed a systematic search of all available randomized controlled trials (RCTs) conducted up to June 2018 in the following electronic databases: PubMed, Scopus, Cochrane, and Google Scholar. RCTs that investigated the effect ginseng supplementation on high‐sensitivity C‐reactive protein (hs‐CRP), tumor necrosis factor‐α (TNF‐α), and interleukin‐6 (IL‐6) were included for final analysis. A total of seven RCTs were included in the meta‐analysis. Results indicated significant reduction in IL‐6 (mean difference [MD]: ?0.265 pg/ml, 95% CI [?0.396, ?0.135], p < .001) and TNF‐α (MD: ?2.471 pg/ml, 95% CI [?2.904, ?2.039], p < .001) and no significant change in hs‐CRP (MD: ?0.125 mg/L, 95% CI [?0.597, 0.347], p = .604). Although there was publication bias across studies, trim and fill analysis showed that results from unpublished studies could not change the results for CRP. However, removing one study in sensitivity analysis did reveal a significant reduction in CRP. We conclude that ginseng supplementation significantly lowered IL‐6 and TNF‐α but did not significantly lower CRP. However, these findings were not robust, because they showed sensitivity for CRP and IL‐6, and future long‐term well‐designed dose‐escalating trials are required.     

Effects of silymarin supplementation on blood lipids: A systematic review and meta‐analysis of clinical trials

Dyslipidemia is a leading cause of endothelial dysfunction and cardiovascular disease. Several studies used silymarin as an herbal supplement in hyperlipidemic subjects. The aim of the present systematic review and meta‐analysis was to examine the effect of silymarin supplementation on blood lipids. PubMed, Scopus, Ovid (Cochrane library), ISI Web of Science, and Google Scholar were systematically searched until March 2018 to find intervention studies that examined the impact of silymarin supplementation on blood lipids in adults. Changes in blood lipids and potential sources of between‐study variation were extracted. We run a subgroup analysis to determine potential sources of inter‐study heterogeneity. Ten clinical trials fulfilled the eligibility criteria. Meta‐analysis indicated that silymarin supplementation in combination with other treatments (not silymarin alone) reduced total cholesterol (change: ?25.45 mg/dl; 95% confidence interval [CI] [?47.89, ?3.01 mg/dl]) and low‐density lipoprotein (change: ?28.25 mg/dl; 95% CI [?53.09, ?3.42 mg/dl]). Also, silymarin increased high‐density lipoprotein concentration (change: 4.82 mg/dl; 95% CI [2.01, 7.63 mg/dl]). Blood concentration of triglyceride was significantly after silymarin supplementation in comparison with controls (change: ?22.55 mg/dl; 95% CI [?44.32, ?0.78 mg/dl]). Present systematic review and meta‐analysis revealed that silymarin supplementation in combination with other treatments had a favorable effect on blood lipids.     

Effects of garlic supplementation on liver enzymes: A systematic review and meta‐analysis of randomized controlled trials

Current evidence on the beneficial effects of garlic on liver enzymes is contradictory. Therefore, the aim of this systematic review and meta‐analysis is to evaluate the effect of garlic supplementation on human liver enzymes, such as Alanine Transaminase (ALT/SGPT) and Aspartate Transaminase (AST/SGOT). To collect the required data, PubMed, Scopus, ISI Web of Science, and Google scholar databases were systematically searched from inception to June 2019. A meta‐analysis was conducted using the random‐effects model to evaluate the effects of garlic supplementation on ALT and AST levels. The Cochran's Q‐test and inconsistency index were also used to evaluate heterogeneity among the studies. Among a total of 15,514 identified articles, six studies (containing 301 participants) met the inclusion criteria. Results of the meta‐analysis showed that garlic supplementation significantly decreased AST level (Hedges' g = ?0.36, 95% confidence interval [CI]: ?0.72, ?0.004, p = .047); whereas, it had no significant effect on ALT level (Hedges' g = ?0.22, 95% CI: ?0.64, 0.20, p = .310). Results showed that garlic supplementation reduced AST levels significantly; however, had no significant effect on ALT levels. Further studies are still needed to confirm the results.     

The efficacy of sour tea (Hibiscus sabdariffa L.) on selected cardiovascular disease risk factors: A systematic review and meta‐analysis of randomized clinical trials

This study sought to summarize clinical evidence of sour tea (Hibiscus sabdariffa L.) administration on cardiovascular disease risk factors. PubMed, Scopus, Institute for Scientific Information Web of Science, and Google Scholar were systematically searched from inception to June 2019 to identify randomized clinical trials, which assessed the effect of sour tea consumption on lipid profiles, fasting plasma glucose, and blood pressure in adult populations. Mean and standard deviation for each parameter were extracted to calculate effect size. Cochrane Collaboration tools were used to evaluate risk of bias assessment. A total of seven randomized clinical trials consisting 362 participants were included in the meta‐analysis. Pooled effect size demonstrated that sour tea consumption significantly reduces fasting plasma glucose (?3.67 mg/dl, 95% confidence interval, CI [?7.07, ?0.27]; I² = 37%), systolic blood pressure (?4.71 mmHg, 95% CI [?7.87, ?1.55]; I² = 53%), and diastolic blood pressure (?4.08 mmHg, 95% CI [?6.48, ?1.67]; I² = 14%). Although no significant effect was observed on triacylglycerol, total cholesterol, and high‐density lipoprotein cholesterol following sour tea consumption, a trend toward a significant reduction was found in low‐density lipoprotein cholesterol serum concentrations (p = 0.08). This systematic review and meta‐analysis suggests that sour tea consumption could have beneficial effect in controlling glycemic status and blood pressure among adult population.     

Efficacy and safety of Tripterygium wilfordii Hook. f. for oral lichen planus: Evidence from 18 randomized controlled trials

Glycosides from the roots of Tripterygium wilfordii Hook. f. are used for the treatment of oral lichen planus (OLP), a chronic inflammatory disease affecting the oral mucosa. To investigate the effectiveness and safety of Tripterygium glycosides (TGs) for OLP treatment, we conducted a systematic review of 18 randomized controlled trials, comprising 1,339 participants, from international and Chinese databases. We evaluated outcomes of TGs alone or in combination with conventional treatments. In combination with topical glucocorticoids (TGCs), including triamcinolone acetonide and prednisone, the total effectiveness rate (risk ratio [RR], 1.17; 95% confidence interval [CI], 1.09–1.25; p < .00001), symptom score reducing index (mean difference [MD], ?2.44; 95% CI, ?3.12 to ?1.77; p < .0001), and visual analog scale score (MD, ?1.61; 95% CI, ?2.22 to ?1.00; p < .0001) were significantly improved. Patients treated with TGs combined with TGCs experienced lower recurrence rates (RR, 0.37; 95% CI, 0.18–0.76; p = 0.007). The occurrence of adverse events was not significantly different between the TGs groups and controls. The combination of TG and TGCs improved clinical efficacy and reduced recurrence without increasing the risk of adverse events. A high‐quality multicenter clinical study is needed to corroborate these findings.     

Adjuvant Treatment with Yupingfeng Formula for Recurrent Respiratory Tract Infections in Children: A Meta‐analysis of Randomized Controlled Trials

This meta‐analysis aimed to evaluate the immunomodulating function of Yupingfeng Formula (YPFF) in children with recurrent respiratory tract infections (RRTIs). The PubMed, EMBASE, Cochrane Library, CNKI and WanFang databases were searched for randomized controlled trials comparing with and without YPFF for RRTIs in children. Twelve trials with 1236 patients were identified. Adjuvant treatment with YPFF significantly increased serum levels of IgA (weighted mean difference [WMD] 0.33 mg/mL; 95% confidence interval [CI] 0.20 to 0.45), IgG (WMD 1.36 mg/mL; 95% CI 1.06 to 1.65), IgM (WMD 0.16 mg/mL; 95% CI 0.02 to 0.31), and CD3⁺ T‐lymphocytes (WMD 10.16%; 95% CI 4.62 to 15.69) but not CD4⁺ T‐lymphocytes (WMD 3.16%; 95% CI ?0.27 to 6.59) and CD8⁺ T‐lymphocytes (WMD ?0.84%; 95% CI ?2.50 to 0.81). YPFF also reduced the frequency of RRTIs (WMD ?3.80 times; 95% CI ?4.86 to ?2.74) and increased total effective rates of symptom improvement (risk ratio: 1.44; 95% CI 1.19 to 1.75). Adjuvant treatment with YPFF could improve total clinical effective rate and decrease the frequency of respiratory tract infections in children with RRTIs. The beneficial effects of YPFF may be correlated to its immunomodulating action. More well‐designed trials with larger sample sizes are needed to evaluate its efficacy and safety. Copyright © 2016 John Wiley & Sons, Ltd.     

Dietary citrus and/or its extracts intake contributed to weight control: Evidence from a systematic review and meta‐analysis of 13 randomized clinical trials

Randomized controlled trials, being published in English and investigating the associations of at least 4 weeks intervention of citrus and/or its extracts on weight loss among adults, were searched from PubMed, Web of Science, Scopus, and Cochrane by June 2019 to conduct a meta‐analysis. Thirteen articles, including 921 participants, were selected and evaluated by modified Jadad scale. Pooled results by the random‐effects model showed that citrus and/or its extracts administration significantly reduced 1.280 kg body weight (95% CI: ?1.818 to ?0.741, p = 0.000, I² = 81.4%), 0.322 kg/m² BMI (95% CI: ?0.599 to ?0.046, p = 0.022, I² = 87.0%), 2.185 cm WC (95% CI: ?3.804 to ?0.566, p = 0.008, I² = 98.3%), and 2.137 cm HC (95% CI: ?3.775 to ?0.500, p = 0.011, I² = 96.2%), respectively, but no significantly decreased effects on WHR and body fat were observed. Subgroup analysis deduced the different effects of study location, intervention duration on body weight associated indices. No publication bias was observed. Our meta‐analysis supported the beneficial effects of citrus and/or its extracts supplement on body weight control, and future well‐designed studies are required to firmly establish the clinical efficacy of citrus and/or its extracts intervention on body weight.     

Topical Herbal Formulae in the Management of Psoriasis: Systematic Review with Meta‐Analysis of Clinical Studies and Investigation of the Pharmacological Actions of the Main Herbs

This systematic review and meta‐analysis of randomized controlled trials (RCTs) examined the topical use of multi‐herbal formulations for the management of psoriasis vulgaris. Studies were identified from PubMed, Cochrane library, EMBASE, and the Chinese databases CNKI and CQVIP. Methods were according to the Cochrane Handbook and meta‐analyses used RevMan 5.1. Nine studies met the inclusion/exclusion criteria. The comparisons were with placebo and/or anti‐psoriatic pharmacotherapy (APP) with two studies having three arms. The pooled meta‐analysis data indicated the topical herbal formulae improved overall clinical efficacy (defined as 50% improvement or greater) when compared with: topical placebo (plus oral herbal co‐intervention); topical APP alone; and topical APP (plus pharmaceutical co‐intervention). Improvement was evident in Modified Psoriasis Area and Severity Index (PASI) score when topical herbal formula was compared to placebo (plus oral herbal co‐intervention). No serious adverse events were reported. The most commonly used herbs were Sophora flavescens root and Lithospermum erythrorhizon root. Experimental studies reported that these herbs and/or their constituents have anti‐inflammatory, anti‐proliferative, anti‐angiogenic, and tissue repair actions. These actions may at least partially explain the apparent benefits of the topical multi‐herbal formulations in psoriasis. Copyright © 2013 John Wiley & Sons, Ltd.     

Effects of cardamom supplementation on lipid profile: A systematic review and meta‐analysis of randomized controlled clinical trials

Cardiovascular disease is a highly prevalent issue worldwide and one of its main manifestations, dyslipidemia, needs more attention. Recent studies have suggested that cardamom has favorable effects beyond lipid lowering, but the result are contradictory. Our objective was to conduct a systematic review and meta‐analysis on randomized controlled trials (RCTs) that assessed the effect of cardamom on lipids. The search included PubMed, Scopus, ISI Web of Science, Google Scholar, and the Cochrane library (up to March, 2019) to identify RCTs investigating the effects of cardamom supplementation on serum lipid parameters. Weighted mean differences (WMDs) were pooled using a random‐effect model. Meta‐analysis of data from five eligible RCTs showed that cardamom supplementation did not significantly change the concentrations of total cholesterol (WMD: ?6.11 mg/dl, 95% CI [?13.06, 0.83], I² = 0.0%), low‐density lipoprotein cholesterol (WMD: ?4.31 mg/dl, 95% CI [?9.75, 1.13], I² = 0.0%), or high‐density lipoprotein cholesterol (WMD: 1.75 mg/dl, 95% CI [?1.95 to 5.46], I² = 71.4%). However, a significant reduction was observed in serum triglyceride (TG; WMD: ?20.55 mg/dl, 95% CI [?32.48, ?8.63], I² = 0.0%) levels after cardamom supplementation. Cardamom might be able to change TG, but for confirming the results, more studies exclusively on dyslipidemia patients and considering the intake of lipid lowering agents as exclusion criteria are necessary.     

The effects of spirulina on glycemic control and serum lipoproteins in patients with metabolic syndrome and related disorders: A systematic review and meta‐analysis of randomized controlled trials

The aim of this systematic review and meta‐analysis was to evaluate the effects of spirulina on glycemic control and serum lipoproteins in patients with metabolic syndrome (MetS) and related disorders. Two independent authors systematically searched online database including EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until April 30, 2019. The Cochrane Collaboration's risk of bias tool was applied to assess the methodological quality of included trials. The heterogeneity among the included studies was assessed using Cochrane's Q test and I‐square (I²) statistic. Pooling effect sizes from studies showed a significant reduction in fasting plasma glucose (FPG; weighted mean difference [WMD]: ?10.31; 95% confidence interval, CI [?16.21, ?4.42]) and insulin concentrations (WMD: ?0.53; 95% CI [?0.62, ?0.44]) following the administration of spirulina. Pooled analysis showed also a significant reduction in total cholesterol (WMD: ?20.50; 95% CI [?38.25, ?2.74]), low‐density lipoprotein cholesterol (LDL‐C; WMD: ?19.02; 95% CI [?36.27, ?1.78]), and very low‐density lipoprotein cholesterol (VLDL‐C) concentrations (WMD: ?6.72; 95% CI [?9.19, ?4.26]) and a significant increase in high‐density lipoprotein cholesterol (HDL‐C) levels (WMD: 1.42; 95% CI [0.16, 2.68]) following spirulina therapy. This meta‐analysis demonstrated the beneficial effects of spirulina supplementation on improving FPG, insulin, total cholesterol, LDL‐C, VLDL‐C, and HDL‐C levels in patients with MetS and related disorders.     

The influence of green coffee bean extract supplementation on blood glucose levels: A systematic review and dose–response meta‐analysis of randomized controlled trials

Studies regarding the influence of green coffee extract (GCE) on blood glucose levels are conflicting. Thus, we sought to conduct a meta‐analysis and systematic review of all available randomized controlled trials (RCTs) to quantify the effects of GCE and CGA intervention on blood glucose and insulin levels. We performed systematic online searches in Scopus, Web of science, and PubMed databases, from inception to July 2019. Data were combined analyzed using a random effects model (Der Simonian‐Laird method) and reported as weighted mean differences (WMD). Ten trials reported the influences of GCE on FBS and insulin and were subsequently entered into the meta‐analysis. Combined results highlighted that FBS was significantly altered after GCE consumption (WMD: ?1.791 mg/dl, 95% CI ?3.404, ?0.177), with no significant heterogeneity among the studies (I² = 35.0%, p = .128). However, overall results demonstrated that GCE administration did not result in any significant alteration in insulin levels (WMD: ?0.925 μU/ml, 95% CI:?1.915, 0.064), with significant heterogeneity found across studies (I² = 87.9%). In sub‐group analysis, insulin levels were significantly reduced when GCE was supplemented in dosages of ≥400 mg/day (WMD:?1.942 mg/dl, 95% CI:?1.184, ?0.975; I² = 0.0%). The results of present study support the use of GCE for the enhancement of blood glucose, while subgroup analysis highlighted significant improvements in insulin levels when GCE is supplemented in doses ≥400 mg/day.     

Effect of purslane on blood lipids and glucose: A systematic review and meta‐analysis of randomized controlled trials

Despite a history of purslane usage as a herbal treatment for dyslipidemia and hyperglycemia management, existing evidence from clinical trials is controversial. The aim for the current study was to evaluate the efficacy of purslane supplementation on lipid parameters and glycemic status in adult populations. A systematic review was conducted in PubMed, Scopus, ISI Web of Science, and Google Scholar up to January 15, 2018, searching for randomized controlled trials that assessed the impact of purslane on fasting blood glucose (FBG), triglycerides, total cholesterol (TC), low‐density lipoprotein cholesterol (LDL‐C), and high‐density lipoprotein cholesterol (HDL‐C). Based on the detected heterogeneity between studies, a random‐ or fixed‐effect model was applied in the meta‐analysis. The findings from six randomized controlled trials, comprising 352 participants, indicated that purslane can reduce FBG (?4.54 mg/dl, 95% CI [?7.54, ?1.53]; I² = 0.53%) and triglycerides (?19.16 mg/dl, 95% CI [?38.17, ?0.15]; I² = 0%) levels. Changes in TC, LDL‐C, and HDL‐C concentrations did not reach a statistically significant level. Subgroup analysis showed a favorable effects of purslane on FBG, triglycerides, TC, and LDL‐C in a subset of studies in which purslane was administered >1.5 g/day. Categorization based on gender showed that purslane was more effective in improving FBG, TC and LDL‐C in females compared with males. This systematic review and meta‐analysis suggested that the purslane might be effective on the improvement of blood lipid and glucose levels. Further robust studies with sufficient durations and dosages of supplementation are needed to confirm these results.     

Does turmeric/curcumin supplementation improve serum alanine aminotransferase and aspartate aminotransferase levels in patients with nonalcoholic fatty liver disease? A systematic review and meta‐analysis of randomized controlled trials

We performed a meta‐analysis to evaluate the efficacy of turmeric/curcumin supplementation on serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in patients with nonalcoholic fatty liver disease (NAFLD). We searched PubMed, Scopus, Cochrane Library, ISI Web of Science, and Google Scholar up to November 20, 2018. Studies that examined the effect of turmeric/curcumin on serum concentrations of ALT and AST among patients with NAFLD were included. The mean difference and standard deviation (SD) of changes in ALT and AST between intervention and control groups were used as effect size for the meta‐analysis. A total of six randomized controlled trials (RCTs) were eligible for meta‐analysis. Results from pooled analysis revealed that turmeric/curcumin supplementation reduced ALT (MD: ?7.31 UL/L, 95% CI [?13.16, ?1.47], p = 0.014) and AST (MD: ?4.68 UL/L, 95% CI [?8.75 ?0.60], p = 0.026). When RCTs stratified on the basis of their treatment duration, the significant reduction in serum concentrations of ALT and AST was observed only in studies lasting less than 12 weeks. This review suggests that turmeric/curcumin might have a favorable effect on serum concentrations of ALT and AST in patients with NAFLD. However, further clinical trials are needed to confirm these findings.     

The impact of argan oil on plasma lipids in humans: Systematic review and meta‐analysis of randomized controlled trials

The study aims to investigate the effect of argan oil on plasma lipid concentrations through a systematic review of the literature and a meta‐analysis of available randomized controlled trials. Randomized controlled trials that investigated the impact of at least 2 weeks of supplementation with argan oil on plasma/serum concentrations of at least 1 of the main lipid parameters were eligible for inclusion. Effect size was expressed as the weighted mean difference (WMD) and 95% confidence interval (95% CI). Meta‐analysis of data from 5 eligible trials with 292 participants showed a significant reduction in plasma concentrations of total cholesterol (WMD: ?16.85 mg/dl, 95% CI [?25.10, ?8.60], p < .001), low‐density lipoprotein cholesterol (WMD: ?11.67 mg/dl, 95% CI [?17.32, ?6.01], p < .001), and triglycerides (WMD: ?13.69 mg/dl, 95% CI [?25.80, ?1.58], p = .027) after supplementation with argan oil compared with control treatment, and plasma concentrations of high‐density lipoprotein cholesterol (WMD: 4.14 mg/dl, 95% CI [0.86, 7.41], p = .013) were found to be increased. Argan oil supplementation reduces total cholesterol, low‐density lipoprotein cholesterol, and triglycerides and increases high‐density lipoprotein cholesterol levels. Additionally, larger clinical trials are needed to assess the impact of argan oil supplementation on other indices of cardiometabolic risk and on the risk of cardiovascular outcomes.     

The effect of soy intervention on insulin‐like growth factor 1 levels: A meta‐analysis of clinical trials

A low insulin‐like growth factor 1 (IGF‐1) level is known to be associated with many disorders. Several studies have shown that soy consumption may influence IGF‐1, but the findings remain inconclusive. In this work, we conducted a systematic review and meta‐analysis to provide a more accurate estimation of the effect of soy consumption on plasma IGF‐1. A comprehensive systematic search was performed in Scopus, Embase, Web of Science, and PubMed/MEDLINE databases from inception until October 2019. Eight studies fulfilled the eligibility criteria. The pooled weighted mean difference (WMD) of the eligible studies was calculated with random‐effects approach. Overall, a significant increment in plasma IGF‐1 was observed following soy intervention (WMD: 13.5 ng/ml, 95% CI: 5.2, 21.8, I² = 97%). Subgroup analyses demonstrated a significantly greater increase in IGF‐1, when soy was administered at a dosage of ≤40 g/day (WMD: 11.7 ng/ml, 95% CI: 10.9 to 12.6, I² = 98%), and when the intervention duration was <12 weeks (WMD: 26.6 ng/ml, 95% CI: 9.1 to 44.1, I² = 0.0%). In addition, soy intervention resulted in a greater increase in IGF‐1 among non‐healthy subjects (WMD: 36 ng/ml, 95% CI: 32.7 to 39.4, I² = 84%) than healthy subjects (WMD: 9.8 ng/ml, 95% CI: 8.9 to 10.7, I² = 90%). In conclusion, this study provided the first meta‐analytical evidence that soy intake may increase IGF‐1 levels, but the magnitude of the increase is dependent on the intervention dosage, duration, and health status of the participants.     

Effect of garlic supplementation on serum C‐reactive protein level: A systematic review and meta‐analysis of randomized controlled trials

The present study was designed to systematically review randomized controlled trials (RCTs) that report on the effects of garlic supplementation on serum C‐reactive protein (CRP) levels. We conducted a literature search of Scopus, PubMed, Cochrane Library, and Google Scholar up to January 2018. Weighted mean differences (WMD) were estimated for net change in serum CRP. Subgroup analyses were also performed by duration of study, dose of supplementation, baseline CRP level, and the quality of studies. From 438 articles found and screened in our initial search, nine RCTs with the sum of total sample size of 363 were included in the meta‐analysis. Compared with the controls, garlic intake significantly reduced the concentrations of serum CRP by 0.8 mg/L (95% CI [?1.5, ?0.1], p = 0.02) with the evidence of heterogeneity among studies. Subgroup analyses showed that garlic significantly lowered CRP by 0.82 mg/L (95% CI [?1.02, ?0.62], p < 0.001) among studies with a daily garlic dose ≥1,200 mg/day and by 2.44 mg/L (95% CI [?4.02, ?0.87], p = 0.002) among studies with baseline CRP ≥2 mg/L. Current data confirmed that garlic supplementation would reduce serum CRP levels. However, the changes were related to the supplemental doses and baseline levels of serum CRP.