Global Association between Traditional Japanese Diet Score and All-Cause, Cardiovascular Disease, and Total Cancer Mortality: A Cross-Sectional and Longitudinal Ecological Study.

Objective: Studies conducted on Japanese people have suggested that a traditional Japanese diet contributes to good health, longevity, and protection against several non-communicable diseases. However, it is unknown whether traditional Japanese dietary patterns are associated with all-cause mortality, cardiovascular disease, and cancer mortality globally. The purpose of this cross-sectional and longitudinal ecological study is to clarify the global association between the traditional Japanese diet score (TJDS) and all-cause, cardiovascular disease, and total cancer mortality.

Methods: Data on food supply and all-cause mortality, cardiovascular disease mortality, total cancer mortality, and covariables by country were obtained from a relevant internationally available database. TJDS by country was calculated from eight food groups and the total score ranged from -8 to 8, with higher scores indicating greater adherence to a traditional Japanese diet. We evaluated the cross-sectional and 10-year longitudinal association between TJDS and all-cause, cardiovascular disease, and total cancer mortality using 2009 as the baseline in 142 countries with populations of more than one million. A cross-sectional analysis and a longitudinal analysis were performed using three general linear models or three linear mixed models with different covariables.

Results: In cross-sectional models controlled for fully-adjusted covariables, TJDS was negatively associated with all-cause mortality (β ± standard error; -43.819 ± 11.741,  < 0.001), cardiovascular disease mortality (-22.395 ± 4.638,  < 0.001), and total cancer mortality (-3.893 ± 1.048,  < 0.001). In 10-year longitudinal models controlled for fully-adjusted covariables, TJDS was significantly negatively associated with all-cause mortality (-31.563 ± 7.695,  < 0.001), cardiovascular disease mortality (-16.249 ± 4.054,  < 0.001), and total cancer mortality (-3.499 ± 0.867,  < 0.001).

Conclusions: This cross-sectional and longitudinal ecological study suggests that the traditional Japanese diet is associated with lower all-cause mortality, cardiovascular disease mortality, and total cancer mortality, worldwide.