Systematic Reviews
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Feb 15, 2019; 10(2): 96-113
Published online Feb 15, 2019. doi: 10.4239/wjd.v10.i2.96
Effectiveness of royal jelly supplementation in glycemic regulation: A systematic review
Kamel Omer, Maxwell J Gelkopf, Genevieve Newton
Kamel Omer, Maxwell J Gelkopf, Genevieve Newton, Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada
Author contributions: Omer K and Newton G conceptualized research question and created search strategy; Omer K and Gelkopf MJ conducted full text inclusions and risk of bias assessments; Omer K and Newton G conducted GRADE assessment; Newton G reviewed manuscript throughout writing stage; Omer K conducted database search, data extraction and analysis, and manuscript preparation.
Conflict-of-interest statement: The authors declare no conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Genevieve Newton, BSc, MSc, PhD, Associate Professor, Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G2W1, Canada. newton@uoguelph.ca
Telephone: +1-519-8244120-56822 Fax: +1-519-7635902
Received: November 15, 2018
Peer-review started: November 15, 2018
First decision: November 29, 2018
Revised: January 29, 2019
Accepted: February 11, 2019
Article in press: February 12, 2019
Published online: February 15, 2019
ARTICLE HIGHLIGHTS
Research background

Existing evidence suggests that royal jelly (RJ) is a promising therapeutic option in hyperglycemic cases. Few studies have specifically examined the clinical viability of RJ as treatment, and no study has critically analyzed the existing evidence. Knowledge of the factors that influence effectiveness of RJ intake provides an alternative treatment for hyperglycemia, which is often associated with diabetes.

Research motivation

This systematic review demonstrated that the intervention style (e.g., length of supplementation, ingestion form) as well as pre-existing patient characteristics may be important factors in its effectiveness, and future research should further investigate these factors to inform patients and health care providers.

Research objectives

This review sought to examine whether there is support for RJ as a glycemic regulator in models of type 2 diabetes as well as healthy individuals. Our analysis found that the existing evidence suggests that RJ is a promising therapeutic option in hyperglycemic cases, with effective doses as low as 1000 mg of fresh RJ daily for diabetic patients.

Research methods

This was a systematic review employing the PRISMA strategy. Five databases were searched using keywords pertinent to the research objectives. Two reviewers conducted full-text screening to select included articles that met eligibility criteria. Relevant information (i.e., intervention style, results, participant characteristics) was extracted from the included articles. Risk of bias was assessed by two reviewers. GRADE, a novel tool developed by Cochrane used to assess overall quality of evidence, was also determined by two reviewers.

Research results

Effective doses of RJ may be as low as 1000 mg of fresh RJ for a diabetic patient. Overall, the quality of evidence for RJ as a treatment is low for long-term effectiveness, and very low for acute effects of RJ consumption.

Research conclusions

Synthesis and analysis of existing studies shows that RJ may be viable as part of a treatment plan in lowering blood sugar. Due to the heterogeneity in studied population and intervention, RJ may have more pronounced effects in certain dosage forms (e.g., fresh RJ) and in certain populations (e.g., postmenopausal females). This information may be useful for individuals and health care practitioners wishing to explore hyperglycemia treatment options.

Research perspectives

Future clinical trials should consider the potential effects of intervention form and length, as well as the effect of participant characteristics to clarify which patient populations or conditions would benefit most from RJ supplementation.