Berberine is a plant extract widely used in clinical practice. This review aimed to summarize and to grade the available evidence on the association between berberine consumption and health-related outcomes. The PubMed, Cochrane Library, and Embase databases were searched for meta-analyses of randomized controlled trials (RCTs) assessing the efficacy and safety of berberine from inception to June 30, 2022. The AMSTAR-2 and GRADE system were used to assess the methodological quality and evidence level of the included meta-analyses. A total of 11 eligible meta-analyses were identified from 235 publications, which were published in peerreviewed journals between 2013 and 2022. The results revealed that berberine significantly affects blood glucose levels, insulin resistance, blood lipids, body parameters and composition, inflammatory markers, colorectal adenomas, and Helicobacter pylori infections as compared to controls. Common side effects of berberine consumption include gastrointestinal symptoms, such as constipation and diarrhea. Berberine is a safe medicinal plant ingredient that improves various clinical outcomes; however, there is a need for improvement of methodological quality in published meta-analyses. Additionally, the clinical effects of berberine need to be confirmed in high-quality RCTs.

BackgroundNigella sativa (N. sativa) consumption has been associated with various health outcomes; however, the results are not completely consistent.ObjectivesThis overview of systematic reviews and meta-analyses aimed to evaluate the reporting and methodological quality, and to grade the available evidence of associations between N. sativa and health outcomes.MethodsPubMed, Cochrane Library, Embase, and Scopus databases were searched from their inception to September 30, 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 statement, Assessment of Multiple Systematic Reviews (AMSTAR) 2 checklist, and Grades of Recommendations, Assessment, Development and Evaluations (GRADE) systems were used to assess the reporting, methodological, and evidence quality for each meta-analysis, respectively. The results were synthesized in a narrative form.ResultsThis overview included 20 eligible meta-analyses published in peer-reviewed journals between 2013 and 2021. The overall methodological quality was relatively poor, with only one moderate quality, four low quality, and 15 critically low quality studies. For reporting quality, items two, five, eight, nine, 15, and 24 need to improve. Among the 110 outcome indicators of the quality of evidence, five were graded as moderate, 17 as low, and 88 as very low. Risk of bias, inconsistency, and imprecision were the main downgrading factors.ConclusionThis overview suggests that N. sativa is beneficial for various clinical outcomes. However, there are certain limitations to reporting and methodological quality. The clinical efficacy of N. sativa requires confirmation in high-quality, large-sample, randomized controlled trials.

Background: Ginseng consumption has been associated with various health outcomes. However, there are no review articles summarizing these reports.Methods: PubMed, Embase, the Cochrane Library of Systematic Reviews, Scopus, CNKI and Wanfang databases were searched from inception to 31 July 2022. The Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) systems were used to assess the methodological quality and quality of evidence in each meta-analysis, and the results were summarized in a narrative form.Results: Nineteen meta-analyses that met the eligibility criteria were identified from among 1,233 papers. The overall methodological quality was relatively poor, with only five studies being low-quality, and 14 critically low-quality. When compared with control treatments (mainly placebo), ginseng was beneficial for improving fatigue and physical function, sexual function, menopausal symptoms, metabolic indicators, inflammatory markers, unstable angina and respiratory diseases. Adverse events included gastrointestinal symptoms and potential bleeding; however, no serious adverse events were reported.Conclusion: This umbrella review suggests that ginseng intake has beneficial therapeutic effects for diverse diseases. However, the methodological quality of studies needs to be improved considerably. In addition, it is imperative to establish the clinical efficacy of ginseng through high-quality randomized controlled trials.