Inverse Association between Fruit and Vegetable Intake and All-Cause Mortality: Japan Public Health Center-Based Prospective Study

Background A dose-response and nonlinear association between fruit and vegetable intake and mortality has been reported in Europe and the United States, but little is known about this association in Asia. Objectives This study aimed to evaluate the association of fruit and vegetable intake with all-cause, cancer, cardiovascular, and respiratory disease mortality in a Japanese cohort. Methods In the Japan Public Health Center-based prospective study, we included 94,658 participants (mean age: 56.4; 46.0% male) without cancer and cardiovascular disease at baseline. Information on fruit and vegetable intake was collected using a validated FFQ. The Cox proportional hazard model was used to estimate HRs and 95% CIs of each quintile of fruit and vegetable intake, separately, in relation to all-cause and cause-specific mortality using the first quintile as a reference. Nonlinear associations were evaluated using a likelihood ratio test, comparing a linear model with a restricted cubic spline model. Results During a median of 20.9 follow-up years (IQR: 19.6-23.8 y), 23,687 all-cause deaths were documented. After adjusting for age, sex, and potential confounding factors, fruit and vegetable intake was nonlinearly and significantly associated with lower all-cause mortality, with the fourth and fifth quintiles having comparable HRs (fruit: fourth quintile HR: 0.91; 95% CI: 0.87, 0.95 and fifth quintile HR: 0.92; 95% CI: 0.88, 0.96; P-nonlinearity < 0.001; vegetable: fourth quintile HR: 0.92; 95% CI: 0.88, 0.97 and fifth quintile HR: 0.93; 95% CI: 0.89, 0.98; P-nonlinearity = 0.002). Fruit intake was significantly associated with lower cardiovascular mortality (HR in the fifth quintile: 0.91; 95% CI: 0.83, 0.99; P-nonlinearity = 0.01). Conclusions In the Japanese population, higher intake of fruits and vegetables was nonlinearly associated with decreased all-cause mortality. These findings may contribute to the establishment of dietary recommendations for enhancing life expectancy in Asia.