Efficacy and Safety of Nutrient Supplements for Glycaemic Control and Insulin Resistance in Type 2 Diabetes: An Umbrella Review and Hierarchical Evidence Synthesis
Round 1
Reviewer 1 Report
This study answered the research question and it highlighted the very important issues regarding the efficacy and safety of nutrient supplements for glycemic control and insulin resistance in type 2 diabetes: an umbrella review and hierarchical evidence synthesis
This study is well designed and written.
This study highlighted the most important refrences which has been explored the same issue.
Author Response
Thank you for your kind review of our paper.
Reviewer 2 Report
The author conducted a comprehensive umbrella review on the efficacy and safety of nutrient supplements for glycemic control and insulin resistance among people with type 2 diabetes. The method is appropriate, and the conclusion is congruent with the results. To improve the manuscript, I have one minor comment.
Line 64, it is good that the authors clearly stated that dietary supplements were not recommended to people with diabetes who do not have the underlying deficiencies. In the current umbrella review, how many of the included participants were diabetic with or without deficiencies. This needs to be further discussed in the Discussion.
Author Response
Thank you very much for your comment. It is a great suggestion and we have revised as follows:
- Added information to the Outcomes- Glycemic control column in Table 1 and to the descriptions in the text on pages 15 and 17 where subgroup analyses had been done by baseline vitamin/mineral concentration. Only the Folate (Lind) and Vitamin C (Mason) MAs had conducted these. No differences were observed.
- In the Discussion, lines 261-266 we have modified to read "Only two meta-analyses conducted subgroup analyses according to baseline vitamin/mineral concentrations [40,42]. Future research should also clearly identify if nutrient supplements have a greater benefit in people with identified nutrient deficiencies at baseline. Other sub-populations who would most benefit from supplementation should also be identified, such as people with poorer glycemic control at baseline."
We trust this is an improved version of the manuscript.