Abstract
INTRODUCTION: While a balanced diet is crucial for human health, the food system is also a key driver of climate change. The EAT-Lancet Commission developed the Planetary Health Diet (PHD), providing guidelines for a healthy and sustainable diet. OBJECTIVES: The aim of this study was to examine the association of PHD adherence with mortality in Switzerland. METHODS: In this analysis, data from the cross-sectional national nutrition survey menuCH (2014-2015, n=2057) were linked with Swiss mortality and census data (2015-2019). By applying the multiple source method, habitual food intake was calculated based on the reported dietary intakes of two 24- hour dietary recalls and information on food avoidance obtained through a self-administered questionnaire. PHD adherence was quantified using a score that was used to categorise participants (G1, 0-5 points; G2, 6 points; G3, 7 points; G4, 8-14 points). Regression models were fitted to assess the association of the PHD score with all-cause and cause-specific mortality. Spatial autocorrelation of residuals was evaluated using Moran's I statistic. RESULTS: A higher PHD score was associated with lower mortality from diseases of the circulatory system (per 1-point increment: rate ratio=0.98 (95% CI 0.97 to 1.00); G4 vs G1, 0.94 (0.88 to 1.00)). In female participants, a higher PHD score was associated with a lower risk of mortality from diseases of the circulatory system (per 1-point increment: 0.97 (0.94 to 0.99)). In male participants, a higher PHD score was associated with lower all-cancer mortality risk (per 1-point increment: 0.98 (0.96 to 1.00); G4 vs G1, 0.92 (0.86 to 0.99)). CONCLUSIONS: This study generally indicates an inverse association between PHD adherence and mortality risk, especially for diseases of the circulatory system, although the associations varied among subgroups. This study provides further evidence on the potential beneficial effects of sustainable and balanced diets on human health.