Harvard Study Finds DASH Diet Best for Brain Health

A long-term study led by Harvard researchers analyzed data from 159,347 participants over nearly three decades and compared six dietary patterns. The DASH (Dietary Approaches to Stop Hypertension) diet showed the strongest association with reduced cognitive decline, providing a 41 % lower risk of memory weakening compared with the lowest adherence group. Participants following DASH also performed better on memory and working‑memory tests, with brain imaging resembling that of people almost a year younger.

The diet emphasizes fruits, vegetables, whole grains, legumes, nuts and low‑fat dairy while limiting sodium, red and processed meats, sugary drinks, and excess fat. Benefits were most pronounced in adults aged 45‑54, suggesting early adoption maximizes protection. Although the Mediterranean diet still showed modest advantages (16 % lower risk), researchers concluded that DASH offers the most consistent cognitive benefits of the diets examined.