A Comprehensive Review of the Effects of Glycemic Carbohydrates on the Neurocognitive Functions Based on Gut Microenvironment Regulation and Glycemic Fluctuation Control

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have written an interesting review of the literature describing the association between glucose/readily digestible carbohydrates and cognitive function. The review is thorough in its explanation of possible mechanisms and the role of the intestinal microbiota.

Comments:

1) Despite certification of English editing, the manuscript contains a large number of errors. Repeat editing is required. For example:

Line 17: prone is an incorrect term. Prefer "which may lead to cognitive impairment."

39: "It" should be "They mainly consist.."

44: "fat" is not a disease.

79, 81: lower-case M for monosaccharides & malto-oligo...

91: "that" change to "toward incrementally.. become"

98: define GL

119: "instant" change to acute

132, 133: Throughout the manuscript text (the tables show the species), the authors fail to specify the animal model. When "childhood/adolescence" is stated, this usually assumes human. Be clear about the animal used in the studies cited.

141: "older" what?

175: "researches" is not correct.

Table 1: suggest "research model" instead of "object"

183: "reduced gut microbiota" - do you mean reduced diversity?

186: "increased" gut barrier integrity - do you mean "impaired"?

216: be transported

221: what is "appropriate"?

227: the gut microbiota

231: "decreased" gut microbiota?

259: as stated above, species/model must be specified. Bumblebees are far removed from humans.

266: 20% of the oxygen...25% of the glucose...

274, 517: "metabolisms" is not correct.

306-314 & elsewhere: the bolded letters within a paragraph are not proper English. Use indentations or "First..." "Second..."

Do you reference Figure 1 A in the text?

538: hyperglycemia is not a disease

540: change "maleficant" to pathogenic.

544: change "detected" to associated with

561: why do you call it "subtle"?

579: remove "once"

620: why do you state that children have "weak" gut function?

629: Specify the species.

664, 665: These are incomplete sentences.

667: study models

668: clarify what you mean in stating that dietary interventions are "mild"; why are they time-consuming?

677, 678: does modern society really exhibit more mental labor and desire for immediate happiness compared to previous societies?

681: specify "different" - profiles?

682: sentence is incorrect

331: Figure 1 (B)

347, 351: use upper-case A B, as you do in the figure.

354: sentence needs correction.

384: "decomposed" change to converted or metabolized.

390: higher than what?

418: low-grade inflammation

462: remove "in their own right."

472: define Orai

 

Comments on the Quality of English Language

Extensive editing is still needed.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

This great review discusses an ill-known cognitive feature of carbohydrate overload (which becomes even more clear in diabetes). The review is, indeed, comprehensive, structured and informative. I have some remarks:

- Section 1-2: The side-effects of the ketogenic diet are treatable and not too dangerous under specialized supervision, which should be noted by the authors. It is still a valuable tool in epilepsy, for instance.

- Table 1-2: Please do group each species apart, as not all results in mice and/or rats can be readily extrapolated to patients.

Comments on the Quality of English Language

Just some minor grammatical errors throughout the text.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have made the appropriate revisions

One additional correction to complete:

Table 2 NNS needs defining in the footnote.

Author Response

Thank you for your suggestion.  We have defined NNS, which stands for non-nutritive artificial sweeteners, in the footnote of Table 2.

Author Response File: Author Response.pdf