This large US study (Tessier et al. 2025) looked at the relationship between diet and healthy ageing in a cohort of more than 100,000 participants followed for up to 30 years.
The researchers examined adherence to eight healthy eating regimes and found that they were all associated with healthy ageing; the Alternative Healthy Eating Index* performing the best overall and the alternative Mediterranean diet also performing strongly. The healthy eating regimes were associated with improved mental health, cognitive performance, freedom from chronic diseases, intact physical function and living to 70 years old. Healthy ageing was linked to increased consumption of fruit, vegetables, whole grains, unsaturated fats, nuts, legumes and low fat diary. In contrast, increased consumption of trans fats, sodium, sugary beverages, red and processed meat was inversely associated with healthy ageing. Higher UPF consumption was also inversely associated with healthy ageing.
The findings were maintained when the authors controlled their data for socioeconomic status and overall healthy lifestyle, indicating that the observed association to healthy ageing was due to adherence to the healthy diet.
* The Alternative Healthy Eating Index is a scoring system developed at Harvard that rates foods according to their risk of causing chronic disease.
Tessier AJ, Wang F, Korat AA, Eliassen AH, Chavarro J, Grodstein F, Li J, Liang L, Willett WC, Sun Q, Stampfer MJ, Hu FB, Guasch-Ferré M. Optimal dietary patterns for healthy aging. Nat Med. 2025 May;31(5):1644-1652. doi: 10.1038/s41591-025-03570-5. Epub 2025 Mar 24. PMID: 40128348; PMCID: PMC12092270.