The effects of Royal Jelly consumption on lipid profile: A GRADE-assessed systematic review and dose-response meta-analysis

Abstract

Background

Inconsistent evidence exists regarding the impact of Royal Jelly (RJ) on cardio-metabolic risk factors. Hence, this meta-analysis aimed to identify this effect.

Method

Database search through PubMed/Medline, Web of Science, and SCOPUS was performed until April 2023 to identify eligible trials. Estimated 95% confidence (CI) and the weighted mean difference (WMD) was used for triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL), and low-density lipoprotein cholesterol (LDL) through the random-effects model.

Results

RJ could significantly reduce TC (WMD: −8.75; 95%CI: −15.50, −1.99; P = 0.01; I² = 68.5%; P _{heterogeneity}= 0.21). The protective effect of RJ against serum TC was stronger in unhealthy participants, ≥ 8 weeks of supplement administration, ≥ 3000 mg/d of RJ, and in both sexes. Neither the all-study combination nor the subgroup analysis showed a significant effect of this supplementation on TG, LDL and HDL. Dose-response analysis showed a greater reduction in HDL and a greater elevation in TG, following higher doses of RJ supplementation. Longer duration of intervention also led to lower LDL levels. In terms of the certainty of the evidence, TG, TC and HDL were regarded as moderate and LDL as low quality.

Conclusions

RJ can reduce the risk of cardiovascular diseases by reducing the level of TC, and long-term supplementation could improve the level of HDL and LDL.