Associations of adherence to a dietary index based on the EAT–Lancet reference diet with cognition, brain volumes, and ecological sustainability parameters: Results from the Rhineland Study
Juliana F. Tavares, Christina‐Alexandra Conzen, Santiago Estrada, Rika Etteldorf, Elvire Nadieh Landstra, Meta M. Boenniger, Ute Nöthlings, Monique M.B. Breteler- Psychiatry and Mental health
- Cellular and Molecular Neuroscience
- Geriatrics and Gerontology
- Neurology (clinical)
- Developmental Neuroscience
- Health Policy
- Epidemiology
Abstract
Background
Food systems play a major role in both human and planetary health. In 2019, the EAT‐Lancet Commission proposed a universal, healthy reference diet, intending to improve environmental sustainability and prevent non‐communicable diseases (Willet et al, 2019). Adherence to the EAT‐Lancet reference diet (ELR‐diet) has been previously associated with lower cardiometabolic diseases and mortality risk (Knuppel et al, 2019; Stubbendorff et al, 2022). However, the effects of the ELR‐diet on brain‐related outcomes remain largely unexplored. Therefore, we quantified the ELR‐diet adherence and its associations with cognitive function, brain structures and ecological sustainability parameters in a population‐based German cohort.
Methods
Our study population consisted of Rhineland Study participants with complete dietary assessment at baseline. We used a semi‐quantitative food frequency questionnaire to estimate ELR‐diet adherence through a 14‐item composite index, based on the EAT‐Lancet Commission recommendations. Diet‐related greenhouse‐gas emissions (GHGEs) and land use (LU) were calculated on the basis of each participant’s total food intake, expressed as kgCO2 equivalents and m2×year, respectively. Cognitive performance was measured in multiple domains (processing speed, executive function, working and episodic verbal memory). These domains were summarized using z‐score averaging, producing a global cognitive function and a total memory score (n = 7017, age 56.2±13.4 years). Brain volumetric measures (total brain, white and grey matter, cortex and hippocampus) were obtained from available T1‐MRI scans (n = 5184, age 55.9±13.4 years) using Freesurfer. We quantified the relationship between ELR‐diet adherence and the outcomes using multivariate linear models adjusted for age, sex, education and BMI.
Results
Higher ELR‐diet adherence (per SD increase) was associated with better global cognitive performance (ß = 0.02, 95%CI = 0.01; 0.03), and executive function (ß = 0.03, 95%CI = 0.01; 0.04), episodic verbal memory (ß = 0.04, 95%CI = 0.02; 0.06) and total memory (ß = 0.02, 95%CI = 0.01; 0.03) domains. Moreover, the ELR‐diet was inversely associated with GHGEs (ß = ‐0.28, 95%CI = ‐0.30; ‐0.25) and LU (ß = ‐0.38, 95%CI = ‐0.41; ‐0.34). No associations between the ELR‐diet and brain volumes were observed.
Conclusion
Our study shows that adherence to the ELR‐diet is associated with favorable cognitive performance and reduced environmental impact, but not with brain volumetric measures. These findings support the potential health and environmental benefits of the EAT–Lancet Commission recommendations.