Adherence to the planetary health diet and healthy aging: A prospective analysis

The Planetary Health Diet Index (PHDI) was designed to align environmental objectives with human health. This is the first study to assess the relationship between the PHDI and healthy aging, measured by intrinsic capacity (IC) and physical frailty.

We analyzed data from 19,505 participants in the UK Biobank cohort. Dietary intake was assessed using two to five 24-h assessments, and the PHDI was constructed based on 15 food groups. IC was assessed according to the Integrated Care for Older People guidelines with a score between 0 and 10 points (higher score indicated higher IC); while frailty was assessed using Rockwood's frailty index (FI) and Fried's frailty phenotype (FP). Linear regression was used to examine the relationship between PHDI and IC, and logistic regression for associations with frailty.

After a median follow-up of 6.25 years, higher adherence to the PHDI was associated with greater IC: the mean difference (95 % CI) for the 3rd vs. 1st tertile of PHDI was 0.46 (0.05, 0.86). Higher adherence to the PHDI was associated with lower frailty risk: the odds ratios comparing extreme tertiles of PHDI were 0.80 (0.71, 0.90) for FI and 0.62 (0.43, 0.88) for FP. Fish & seafood was independently associated with higher IC and less frailty, while whole grains, fruits, vegetables, nuts & seeds and limiting added sugars & juices were linked to lower frailty risk..

In this cohort of British adults, greater adherence to the PHDI was associated with improved IC and lower frailty risk.