Greater adherence to the EAT-Lancet Planetary Health Diet was associated with better executive function, processing speed, semantic fluency, and immediate recall among older adults.
Greater adherence to a planetary health diet is associated with better executive function, processing speed, and semantic fluency among older adults, according to study results presented at the European Academy of Neurology (EAN) 2026 Congress, held from June 27 to 30 in Geneva, Switzerland
The EAT-Lancet Planetary Health Diet was developed to support both human health and environmental sustainability. Little research has examined whether following this dietary pattern is associated with specific domains of cognitive function. Researchers therefore evaluated the relationship between diet quality and cognitive performance in a nationally representative sample of older US adults
The analysis included 2636 adults aged 60 years and older who participated in the National Health and Nutrition Examination Survey from 2003 through 2010. The researchers estimated adherence to the EAT-Lancet dietary pattern by calculating Planetary Health Diet Index scores from two 24-hour dietary recalls. Cognitive function was assessed using the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) battery, the Animal Fluency test, and the Digit Symbol Substitution Test (DSST). Multivariable survey-weighted linear regression analyses were performed to evaluate whether dietary adherence was independently associated with cognitive performance after adjustment for sociodemographic characteristics, lifestyle behaviors, and cardiometabolic risk factors.
These findings support the ‘co-benefit’ of sustainable diets for brain health, suggesting that sustainability-aligned dietary frameworks may serve as an effective strategy for preserving cognitive resilience in an aging population
Higher Planetary Health Diet Index scores were consistently associated with better performance across several cognitive domains. In the fully adjusted model, each 10-point increase in Planetary Health Diet Index score was associated with higher DSST scores (β, 0.9746; P =.0012) and Animal Fluency scores (β, 0.3811; P =.0003), indicating better processing speed, executive function, and semantic fluency
Researchers also observed significant dose-response relationships between increasing adherence to the planetary health diet and better executive function (P-trend =.0008) and semantic fluency (P-trend =.0001)
Higher Planetary Health Diet Index scores were also associated with better immediate recall on the CERAD assessment (Trials 1-3: β, 0.1767; P =.0410). However, no statistically significant association was observed between PHDI scores and delayed recall
“These findings support the ‘co-benefit’ of sustainable diets for brain health, suggesting that sustainability-aligned dietary frameworks may serve as an effective strategy for preserving cognitive resilience in an aging population,” the study author concluded
Ha S. Higher planetary health diet index scores are associated with better executive function and processing speed in older adults. Abstract presented at: EAN 2026; June 27-30, 2026; Geneva, Switzerland. EPO-0008
