People who ate closest to the AHEI pattern had 86% higher odds of aging well#
What did the people who aged well actually eat? In a 30-year study of 105,015 American nurses and health professionals, those whose long-term diets scored highest on the Alternative Healthy Eating Index (AHEI) had 1.86 times the odds of meeting the study's healthy-aging criteria at age 70 or older by the final assessment, compared with those who scored lowest. Every one of the eight healthy dietary patterns tested showed the same direction, with odds ratios from 1.45 to 1.86. The foods that tracked with aging well were the familiar ones: fruit, vegetables, whole grains, unsaturated fats, nuts, legumes and low-fat dairy. Trans fats, sodium, sugary drinks and red or processed meat went the other way1.
This is a pattern, not a prescription. The study observed what people reported eating and what happened to them; it did not assign diets. It shows which eating patterns travel with healthy aging in a particular, well-educated, mostly white population, and it cannot prove the diet caused the outcome. Read with that in mind, it is still one of the more useful long-run datasets on food and aging. The macronutrient basics behind these patterns are in macronutrients explained.
What "healthy aging" meant in this study#
The headline number only makes sense once you know how demanding the finish line was. Participants counted as aging healthily only if they were 70 or older at the final (2016) assessment and met every one of these criteria; deaths before then counted as usual aging2:
| Domain | How it was assessed |
|---|---|
| Free of chronic disease | None of 11 major chronic diseases |
| Cognitive function | At most one reported concern on a subjective cognitive decline questionnaire |
| Physical function | Meeting the study's threshold on the SF-36 physical-limitations questions |
| Mental health | Meeting the study's threshold on a 15-item geriatric depression scale |
Only 9,771 people, 9.3% of the cohort, met all of it after up to 30 years of follow-up1. That is why an odds ratio of 1.86 is meaningful: it is about reaching a hard composite target, not avoiding one disease. When the researchers moved the threshold to age 75, the AHEI association grew stronger (odds ratio 2.24, 95% CI 2.01–2.50). By domain, the AHEI's links were strongest with physical function (odds ratio 2.30) and mental health (2.03).
Eight scoring systems, one shared shape#
The study tested eight established ways of scoring a diet: the AHEI, an alternative Mediterranean index, DASH, MIND, a healthful plant-based diet index, the Planetary Health Diet Index, and two indices built to capture diets linked with inflammation and high insulin. The inflammation and insulin scores were reversed so higher values represented healthier patterns2. They were built for different purposes, from blood pressure to brain health to sustainability, yet all of them pointed the same way.
The AHEI came out on top. It was designed by the same research group in 2012 as an update of an earlier index, built specifically around foods and nutrients that predict chronic disease rather than around official guidelines. In its original validation across 71,495 women and 41,029 men, people in the highest AHEI quintile had a 19% lower risk of major chronic disease (relative risk 0.81, 95% CI 0.77–0.85), slightly stronger than the government-guideline index it was compared with3.
Eight overlapping diet scores pointed in the same direction. The shared shape matters more than which one wins.
The weakest of the eight, the healthful plant-based index, still carried an odds ratio of 1.45 (95% CI 1.35–1.57). Its design carries a lesson of its own. Its creators scored plant foods by quality: whole grains, fruit, vegetables, nuts, legumes, oils and tea or coffee count in its favor, while juices, sugary drinks, refined grains, potatoes and sweets count against it. In their earlier heart-disease analysis, comparing the highest with the lowest tenth of each score, the healthful version was associated with 25% lower coronary heart disease risk (hazard ratio 0.75), while an "unhealthful" plant-based score, high in refined plant foods, was associated with 32% higher risk (1.32)4. "Plant-based" alone is not the pattern; the quality of the plants is.
Ultra-processed food showed the mirror image in the aging study: people in the highest quintile of intake had 32% lower odds of healthy aging than those in the lowest2. The trial evidence on processing and intake is covered in does ultra-processed food make you gain weight?.
What the study can and cannot tell you#
The design is strong for an observational study and still observational. The limits that matter most:
- Who was studied. Nurses and health professionals, 66% women, about 95% of European ancestry, with an average starting age of 53. The authors list limited generalizability themselves.
- How diet was measured. A food-frequency questionnaire of more than 130 items, repeated every four years. That captures long-run habits better than a single recall but still depends on self-report.
- How outcomes were measured. Cognitive and physical function were self-reported, not tested.
- Reverse causation. People already declining may eat differently. The authors state it cannot be completely excluded.
- Funding and interests. The study was funded by US National Institutes of Health grants with support from Canadian and US agencies and the Novo Nordisk Foundation. The senior author disclosed leading a grant funded by the International Nut Council; nuts are among the foods linked with healthy aging.
Two modelling choices also shape the result. Diet scores were adjusted for total energy intake, and body mass index was included as a covariate2. In other words, the associations describe diet quality at a given calorie intake and body size. The study does not rank calorie control against diet quality, and it was not designed to.
A practical framing, separate from the evidence#
The next part is not a finding of the study. It is a way of using it.
If you are tracking food to manage weight, calories and protein are the numbers you already see every day, and that is a reasonable place to keep your attention for weight. The pattern evidence adds a second, slower question: over weeks, does what you eat look like the shared shape above? That question does not need a new score. A few checks are enough:
- Most days include vegetables and fruit, and whole grains or legumes, in more than token amounts. Fiber targets and why they matter are in fiber benefits and targets.
- Fats come mostly from oils, nuts, seeds and fish rather than processed meat and fried food; the evidence behind that swap is in saturated vs unsaturated fat.
- Sugary drinks are occasional, not daily.
- Red and processed meat are one protein source among several, not the default.
A calorie-controlled diet can pass or fail those checks, so they are worth looking at on their own. If you want a named pattern to anchor them, the Mediterranean style is one of the eight, and its weight-loss evidence is weighed separately in the Mediterranean diet and weight loss.
FAQ#
What is the AHEI diet?#
The Alternative Healthy Eating Index is a diet-quality score, not a meal plan. Its authors built it around the foods and nutrients that predict chronic disease risk, rather than around official dietary guidelines. In its 2012 validation, the top quintile had a 19% lower risk of major chronic disease3.
How many people in the 30-year study aged healthily?#
9,771 of 105,015, or 9.3%, met the study's healthy-aging criteria at 70 or older: free of 11 major chronic diseases and meeting its thresholds for cognitive, physical and mental health1.
Does this study prove that diet causes healthy aging?#
No. It is observational, relied on self-reported diets and function, and studied mostly white health professionals. It shows that certain patterns are consistently associated with aging well; reverse causation and other factors cannot be ruled out.
Is a plant-based diet automatically good for aging?#
Not automatically. Scores that reward whole plant foods were associated with better outcomes, while a plant-based score weighted toward refined grains, sweets and sugary drinks was linked to 32% higher coronary heart disease risk, comparing the highest with the lowest tenth4.
Sources#
- Tessier AJ, Wang F, Korat AA, et al. Optimal dietary patterns for healthy aging. Nat Med. 2025;31(5):1644-1652.
- Tessier AJ et al. 2025. Full text: PMC12092270.
- Chiuve SE, Fung TT, Rimm EB, et al. Alternative dietary indices both strongly predict risk of chronic disease. J Nutr. 2012;142(6):1009-1018.
- Satija A, Bhupathiraju SN, Spiegelman D, et al. Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in U.S. Adults. J Am Coll Cardiol. 2017;70(4):411-422.
Source: BurnWeek — "What healthy agers ate: the 30-year diet study, and what it can't tell you", https://burnweek.fit/blog/diet-patterns-for-healthy-aging/. Licensed CC BY 4.0: free to quote or reuse with a link to this page.
