New 30-year research reveals optimal dietary patterns for healthy aging

To enhance overall aging, researchers suggest prioritizing dietary patterns rich in plant-based foods, with moderate inclusion of healthy animal-based foods and lower intake of ultra-processed foods. The study examined adherence to eight patterns, which were all associated with healthy aging.

The study’s authors define healthy aging as reaching 70 free of major chronic diseases while maintaining cognitive, physical, and mental health. They analyzed the midlife diets and health outcomes of 105,015 participants aged 39–69, with up to 30 years of follow-up. 

“Studies have previously investigated dietary patterns in the context of specific diseases or how long people live. Ours takes a multifaceted view, asking: how does diet impact people’s ability to live independently and enjoy a good quality of life as they age?” says co-corresponding author Frank Hu, professor of Nutrition and Epidemiology and chair of the Department of Nutrition at Harvard Chan School, US. 

The study is among the first to examine dietary patterns related to overall healthy aging instead of a specific disease, say the researchers from the Harvard T.H. Chan School of Public Health, University of Copenhagen (Denmark), and University of Montreal (Canada). 

Healthy dietary patterns

The researchers used data from the Nurses’ Health Study (1986–2016) and the Health Professionals Follow-Up Study (1986–2016) for the study published in Nature Medicine. The participants in these studies regularly completed food questionnaires. 

The research team scored participants on their adherence to eight healthy dietary patterns. These patterns emphasize a high intake of fruits, vegetables, whole grains, unsaturated fats, nuts, and legumes. The patterns also include low to moderate intake of healthy animal-based foods such as fish and some dairy products. 

All dietary patterns analyzed emphasize a high intake of fruits, vegetables, whole grains, unsaturated fats, nuts, and legumes.The eight dietary patterns used are the Alternative Healthy Eating Index (AHEI), the Alternative Mediterranean Index, the Dietary Approaches to Stop Hypertension (DASH), the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND), the healthful plant-based diet, the Planetary Health Diet Index, the empirically inflammatory dietary pattern, and the empirical dietary index for hyperinsulinemia.

In addition, the researchers assessed participants’ intake of ultra-processed foods, which are industrially manufactured foods that often contain artificial ingredients, added sugars, sodium, and unhealthy fats. 

No one-size-fits-all diet

The study reveals that adhering to any one of these healthy dietary patterns was linked to overall healthy aging. In total, 9,771 participants (9.3%) aged healthfully. Associations were independent of other lifestyle factors, such as physical activity level, smoking, and body mass index.

“Our findings show that there is no one-size-fits-all diet. Healthy diets can be adapted to fit individual needs and preferences,” says lead author Anne-Julie Tessier, assistant professor in the Department of Nutrition at the University of Montreal, researcher at the Montreal Heart Institute, and visiting scientist at Harvard Chan School.

Higher intake of ultra-processed foods, specifically processed meat and sugary and diet beverages, was associated with lower chances of healthy aging. 

“Since staying active and independent is a priority for both individuals and public health, research on healthy aging is essential,” adds co-corresponding author Marta Guasch-Ferré, associate professor in the Department of Public Health at the University of Copenhagen and adjunct associate professor of nutrition at Harvard Chan School. 

Alternative Healthy Eating Index

At the same time, the researchers identified a leading healthy diet, AHEI. This pattern was developed to prevent chronic diseases. Participants with the highest adherence to this diet had an 86% greater likelihood of healthy aging at age 70 and a 2.24-fold higher likelihood of healthy aging at age 75 than people with the lowest adherence to this pattern. 

A higher adherence to any of the dietary patterns was linked to an increased chance of healthy aging.According to the researchers, the AHEI diet focuses on patterns rich in fruits, vegetables, whole grains, nuts, legumes, and healthy fats and low in red and processed meats, sugar-sweetened beverages, sodium, and refined grains. 

In addition, the Planetary Health Diet Index was a leading diet for healthy aging, which was most strongly associated with maintaining intact cognitive health and surviving to age 70. This pattern considers human and environmental health, prioritizing plant-based foods while limiting intake of animal-based foods.

However, the authors cautioned that their study had several limitations, specifically that the participants were exclusively health professionals. Replicating the study among populations with diverse socioeconomic statuses and ancestries would help generalize the findings. 

Like the dietary patterns analyzed in the study, research links diets high in fruits, vegetables, whole grains, nuts and seeds, and plant-based proteins to various health benefits. For example, U.S. News Report’s 2025 rated the Mediterranean, DASH, Flexitarian, and MIND diets as the best overall diets. The expert panel evaluates diets based on nutritional completeness, health risks and benefits, long-term sustainability, and evidence-based effectiveness. 

Foodservice provider Sodexo promotes a neuroprotective diet based on the MIND diet, and the Gerontological Society of America recommends DASH, MIND, and Mediterranean diets to combat dementia and boost brain health.