Associations between Milk and Dairy Product Intake, Urinary Sodium-to-Potassium Ratio, and Socioeconomic Status in Japanese Male Adolescents

Round 1

Reviewer 1 Report

the manuscript is a good contribution to the field with a novel aperture. The study provideds the scholarship with the hypothesis of reducing salt intake and increase intake of dairy products and fruits on adolescents and and childern football players or their parents. The collected data have been treated properly and statistical analysis highlights the obtained results. I have made corrections within the pdf file for authors to improve their study.

Based on the aforementioned, I suggest a minor revision of the present article prior to further consideration for publication.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Thank you for the opportunity to review your manuscript.

Title: ‘Milk and Dairy Products in Japanese Male Adolescent and Children Football Players Are Independently Associated with the Urinary Sodium-to-Potassium Ratio of Socioeconomic Status’

The work appears significant, and the finding of this study provides important results of the CVD risk in children and adolescents and is original. However, some questions remain unanswered or need clarification.

Major comments:

Urinary potassium levels are dependent on the aldosterone levels of the participants. The variation in the hormonal levels may lead to bias in the urinary K levels (e.g., age-dependent effect). Rule out by doing the transtubular potassium gradient or any other method would be better to mitigate the bias.

Lines 88-89: Please provide the reason for excluding 'single-parent family', which may affect your results. It is not clear on the assessment of educational status based on both parents’ educational levels together or single parent’s educational level separately.

Lines 184-185 and 249-250: Please clearly clarify the dependent and independent variables. The dependent variable should be Na/K ratio, whereas the independent variable should be SES, which may affect your analysis.

Line 95-96: Socio-economic status commonly includes income, educational status, wealth status, employment type, etc. It would be better to use a specific term (i.e., parental educational status) rather than a broad term (SES).

Lines 217-223: Table 2: You have mentioned the creatinine concentration, but it doesn’t appear in the table. Also, no methodology or justification for the measurement of creatinine is mentioned. 

The mean protein intake of the participants is higher than the reference intake for players. Higher protein intake may influence kidney function. It would be better to mitigate.

 

Minor comments

Line 98: It would be better to provide the full forms of SBP and DBP when it appears the first time.

Line 133: It would be better to provide the 95% confidence interval of the interclass correlation coefficient value.

Line 156: Please remove the first-line indentation. 

Line 161, 162, & 164: ‘kg/m2’; 2 should be in superscript.

Line 207: There should be a semicolon after 4.4± 2.1

Line 234: It would be better to incorporate the error bar in the figures.

Line 248: Specify the potential confounding factors you used in the multivariate model.

Line 291: It would be better to include the p-value considered for the adjusted model after the binary model.

Author Response

Please see the attachment.

Author Response File: Author Response.docx