Bee products including propolis, bee wax, pollen and royal jelly (RJ) have been used as medicine from ancient times. A vast number of in-vivo and in-vitro studies as well as clinical trials have been conducted to investigate potential health related properties of RJ. A growing number of clinical trials have been performed to assess effects of RJ ingestion on different metabolic markers including glycemia, with diverse results. In the current meataanalysis, we aimed to evaluate effects of RJ ingestion on glycemic markers compared with placebo and set directions for future research. Electronic databases including Scopus, Pubmed, Scholar, Cochrane, Proquest, SID and Magiran were searched and 5 eligible studies were included in the quantitative analysis. Review Manager Software was used for statistical analysis and random effects model was used for pooling data. A total of 205 participants for FPG and 130 participants for HbA1c were included. The overall analysis revealed that RJ consumption reduced FPG by 0.95 mg/dl (95% CI: -5.83 to 3.87; p = 0.69; I2 = 0%; Tau2 = 0.00) and HbA1c by 0.32 (95% CI: -0.87 to 0.23; p = 0.25; I2 = 69 %; Tau2 = 0.16) which were not statistically significant. Funnel plot demonstrated no publication bias. In conclusion, RJ supplementation did not beneficially affect markers of glycemia. However, due to methodology issues and potential confounders like diet as well as diverse populations, we recommend future studies well designed and well controlled for major confounders so we can update these data to more precise results and more accurate conclusion.
Keywords: Glycemia; Meta-analysis; Royal jelly; Systematic review.
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