Berberine and health outcomes: An umbrella review

Abstract 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 peer‐reviewed 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.