30-Year Harvard Study Identifies Optimal Diet for Healthy Aging

A comprehensive 30-year study led by Harvard University researchers has identified the Alternative Healthy Eating Index (AHEI) as the most effective dietary pattern for promoting healthy aging.

The study, published in Nature Medicine (2025), defined "healthy aging" as reaching 70 without chronic diseases while maintaining good mental and physical health. Researchers tracked the eating habits of over 105,000 participants across three decades, comparing eight different healthy eating guidelines.

The AHEI diet, which emerged as the top performer, emphasizes:

• Fruits and vegetables

• Whole grains

• Nuts and legumes

• Healthy fats

While limiting:

• Red and processed meats

• Sugary drinks

• Salt

Participants with the highest adherence to the AHEI were 86% more likely to be healthy at age 70 compared to those with the lowest adherence. However, researchers noted that all dietary patterns studied showed benefits for healthy aging.

"Our findings also show that there is no one-size-fits-all diet," noted Professor Anne-Julie Tessier from the University of Montreal. "Healthy diets can be adapted to fit individual needs and preferences."

The study takes a unique approach by focusing on overall quality of life rather than just longevity or specific disease prevention. As Professor Frank Hu from Harvard explained, the research examines "how diet impacts people's ability to live independently and enjoy a good quality of life as they age."

While the Mediterranean diet has received significant attention in recent years, these findings suggest the AHEI may offer comparable or superior benefits for those looking to maintain health into their later years.

SOURCE

https://www.sciencealert.com/a-30-year-study-may-have-found-the-single-best-diet-for-healthy-aging