Systematic review and meta‐analysis of anti‐hyperglycaemic effects of Pu‐erh tea

Summary Pu‐erh tea was presumed to have anti‐hyperglycaemic effects with limited evidence. This study uses meta‐analysis to investigate anti‐hyperglycaemic effect of Pu‐erh tea. Five English databases and three Chinese ones were systematically searched up to July 31, 2018. Those databases were searched to identify studies containing keywords of ‘Pu‐erh’, ‘Pu'er’, ‘blood sugar’, ‘blood glucose’ and ‘hyperglycaemia’. RevMan 5 and Stata were then utilized to conduct meta‐analysis. Systematic reviews collected two mice studies with sixteen records for meta‐analysis. Meta‐analysis results showed that Pu‐erh tea has significant anti‐hyperglycaemic effect on mice. Pooled weight mean difference of blood sugar on mice studies were 71 and 116 mg dL−1 at 21st day and 28th day respectively. Meta‐regression disclosed over a longer intervention period showed that Pu‐erh tea can reduce fasting blood glucose. Secondly, a higher dose of Pu‐erh is shown to lower fasting blood glucose more significantly. This Meta‐regression results disclosed over a longer intervention period showed that Pu‐erh tea can reduce fasting blood glucose. Secondly, a bigger dose of Pu‐erh, is shown to lower fasting blood glucose more significantly.