Japanese Diet and Mortality, Disability, and Dementia: Evidence from the Ohsaki Cohort Study

Round 1

Reviewer 1 Report

Dear Authors,

Thank you for the interesting paper. Please consider my comments below.

Please illustrate the Abstract with the main findings providing hazard ratios for all outcomes analysed.

The information provided in the Introduction is very scarce. It is stated that "Japanese people not only have longevity but also a long and healthy life expectancy", but it is not clear compared to what - other countries, world? Also, life expectancy, healthy life expectancy, and the structure of the reasons for death in Japan should be provided here.

Also, the reader might wonder about the main principles of the Japanese diet as it is not so broadly described, for example, as the Mediterranean diet. This information with the main comparisons of the other most popular diets should be provided.

The Methods section should explain how groups (quartiles) of the JDI were constructed. As they first appear only in the Results section.
Also, the Methods section should contain a more detailed description of the covariates used (BMI, smoking, alcohol, total energy intake), possibly in a separate subsection and subsectio of statistical analysis.

Also, please provide Tables illustrating the main findings - numbers of outcomes (deaths and incident cases of disability and dementia) in the groups of JDI, person-years and hazard ratios with the covariates included explained in the footnotes. The Results section in its current status is very difficult to follow.

Author Response

Please see the attachment. Thank you.

Author Response File: Author Response.docx

Reviewer 2 Report

Certainly a valuable summary of the limited systematic experience with the Japanese diet against the background of decades of discussed favorable cardiovascular health. In terms of content, method and language flawless.

Author Response

Thank you very much for your valuale time.

Reviewer 3 Report

This is a well written review authored by experts in the field. The review is well structured and comprehensive.

Author Response

Thank you very much for your valuale time.

Round 2

Reviewer 1 Report

Dear Authors,

Thank you for taking into account my comments and suggestions. Good job!