Association between changes in adherence to the planetary health diet and adiposity and body fat distribution: a cohort study

Background: The longitudinal relationship between planetary heath diets and adiposity remains understudied in Europeans. We investigated the association between changes in adherence to the EAT-Lancet planetary health diet (PHD) and changes in adiposity and body fat distribution. Methods: We evaluated 6845 adults (mean age 49.4 years, 51% women), with repeat assessments in the Fenland Study at baseline (2005-2015) and follow-up (2014-2020). Diet was assessed with food frequency questionnaires and scaled to the PHD Index (PHDI) as a measure of adherence to the PHD (range: 0-140 points). Anthropometry, total fat, visceral, subcutaneous fat and lean mass, and liver fat score was measured at both visits. Multivariable-adjusted linear regression, adjusted for sociodemographic, lifestyle and clinical variables, assessed the association between changes in the PHDI and concurrent changes in adiposity. Findings: for body weight, fat mass, lean mass, subcutaneous fat, visceral fat, and liver fat score (p for interaction<0.05). Interpretation: Increasing adherence to the PHD in midlife may reduce or slow gaining adiposity and improve body fat distribution, with greater magnitude in those already obese. These findings suggest a beneficial impact of adherence to the PHD on adiposity in Europeans.