The study, published in Nature Medicine, examined the association between eight different long-term dietary patterns, ultra-processed food consumption and healthy aging. It is reportedly one of few studies to evaluate dietary association using a multidimensional model that assesses physical, cognitive and mental health as markers of aging.
Using data from up to 30 years of follow up, the AHEI was most strongly associated with healthy aging and maintaining intact physical function and mental health, according to scientists from Harvard T.H. Chan School of Public Health and other institutions in the USA, Canada and Denmark.
Shifting attitudes towards aging
The researchers highlight the shift from a disease-focused approach to aging towards a more positive strategy focused on preserving functional ability and preventing loss of capacity, as recently acknowledged by the World Health Organization.
This approach emphasizes diet as a key factor in preventing chronic disease and supporting overall health and vitality.
“Our findings provide evidence to support that adherence to healthy dietary patterns represents a potential strategy for healthy aging, patterns that particularly are richer in fruits, vegetables, whole grains, unsaturated fats, nuts and legumes, that include some dairy products, and that are lower in trans fats, sodium and red and processed meats,” the researchers wrote.
The Alternative Healthy Eating Index
The Alternative Healthy Eating Index (AHEI) was developed by Harvard T.H. Chan School of Public Health researchers as an alternative to the U.S. Department of Agriculture’s Healthy Eating Index.
The AHEI is oriented towards preventing chronic disease and assigns ratings to foods and nutrients based on evidence of their ability to predict or prevent disease. The AHEI grades people’s diets according to how often they eat certain foods.
For example, eating five or more portions of vegetables would score 10, and eating no vegetables would score zero. Unhealthy options reverse the score, so drinking sugary drinks would score zero, and not drinking them would score 10. Previous research links higher AHEI scores with a lower risk of chronic disease.
Study details
The study used longitudinal questionnaire data from the Nurses’ Health Study (1986–2016) and the Health Professionals Follow-Up Study (1986–2016), totaling 105,015 participants. Of these, 66% were women, and the mean age was 53 years.
It examined the association between long-term adherence to eight healthy dietary patterns, ultraprocessed food consumption and healthy aging over 30 years.
The eight diets included the Alternative Healthy Eating Index (AHEI), Alternative Mediterranean Index (aMED), the Dietary Approaches to Stop Hypertension (DASH), the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND), the healthful plant-based diet (hPDI), the Planetary Health Diet Index (PHDI), the empirically inflammatory dietary pattern (EDIP) and the empirical dietary index for hyperinsulinemia (EDIH).
Healthy aging was assessed according to cognitive, physical and mental health measures and living to 70 years of age free of chronic diseases. The researchers then examined the associations in specific subgroups and looked at the individual nutrients and foods contributing to dietary patterns.
The results revealed that after a follow-up of up to 30 years, 9,771 (9.3%) participants achieved healthy aging.
The pooled cohorts showed that 37.9% of participants reached the age of 70 years, 22.8% remained free of 11 chronic diseases, 33.9% maintained intact cognitive function, 28.1% maintained intact physical function, and 26.5% maintained intact mental health.
Higher adherence to all diets was associated with greater odds of healthy aging. The researchers wrote that AHEI had the strongest association with healthy aging “closely followed by the rEDIH, aMED, DASH, PHDI, MIND, rEDIP and lastly the hPDI.”
“The AHEI was also the most strongly associated with maintaining intact physical function and mental health among individual healthy aging domains,” they added.
The study noted that compared to participants in the lowest quintile, those in the highest AHEI quintile had 86% greater odds of achieving healthy aging using a cut-off of 70 years and over twice greater odds using a cut-off of 75 years.
The PHDI was most strongly associated with surviving to age 70 and intact cognitive health, and the rEDIH (reverse EDIH to allow comparison with other dietary scores) was most strongly associated with being free of chronic diseases.
All the diets examined emphasized consuming fruits, vegetables and whole grains while reducing red and processed meat, but each diet emphasized specific components.
The results also found that a higher intake of ultraprocessed food was associated with lower odds of healthy aging.
“Among the eight dietary patterns examined in this study, a diet that was developed to predict chronic disease risk as measured by the AHEI may confer the highest benefit for healthy aging in both men and women,” the researchers concluded.
Source: Nature Medicine, 1-9. doi: 10.1038/s41591-025-03570-5. “Optimal dietary patterns for healthy aging”. Authors: A. Tessier et al.