(P14-090-23) Planetary Health Diet Index and Risk of Total and Cause-Specific Mortality in Two Prospective Cohort Studies

Objectives: In 2019, the EAT-Lancet Commission proposed a healthy dietary pattern that, along with reductions in food waste and improved agricultural practices, could feed the increasing global population sustainably. We developed a Planetary Health Diet Index (PHDI) to quantify adherence to the EAT-Lancet reference diet. This study assesses the associations between PHDI with total and cause-specific mortality in two prospective cohorts of U.S. men and women.

Methods: We followed 63,081 women from the Nurses’ Health Study and 44,275 men from the Health Professionals Follow-Up Study (1986-2018) who were free of cancer, diabetes, and major cardiovascular diseases at baseline. The PHDI was calculated every 4 years using a semiquantitative food frequency questionnaire. Hazard ratios (HRs) were calculated using multivariable proportional-hazards models.

Results: During follow-up, we documented 25,603 deaths among women and 21,794 among men. When comparing the highest with the lowest quintile of PHDI, the pooled multivariable-adjusted HRs (95%CI) were 0.75 (0.73, 0.77) for all-cause mortality. PHDI was strongly associated with lower risk of deaths from cardiovascular diseases (HR: 0.86; 95%CI: 0.81-0.92), cancer (HR: 0.85; 95%CI: 0.80-0.91), respiratory diseases (HR: 0.50; 95%CI: 0.45-0.56), and neurodegenerative diseases (HR: 0.79; 95%CI: 0.73-0.86). In women, PHDI was also significantly associated with risk of deaths from infectious diseases (HR: 0.51; 95%CI: 0.38-0.70).

Conclusions: In two large US-based prospective cohorts of men and women with up to 34 years of follow-up, higher PHDI was associated with lower risk of total and cause-specific mortality.

Funding Sources: This work was supported by research grants from the National Institutes of Health.