A new study published in the journal Nature has found that following a Mediterranean diet can lower the risk of dementia by at least 35% in people with two copies of the APOE4 gene, a major risk factor for Alzheimer’s. The study followed over 5,700 people for 34 years and found those who adhered to a baseline Mediterranean diet rich in vegetables, fruits, nuts, whole grains, legumes, fish, and olive oil had reduced the risk of dementia.
The benefit was highest for individuals with two copies of APOE4 genes. The study also revealed that people with this gene variant have distinct metabolic profiles that respond to healthy nutrients in the Mediterranean diet. Improving metabolic function through diet may explain the significant fall in dementia risk observed in the study.
Neurologist Dr. Richard Isaacson described the findings as a “stop the presses” moment, suggesting that it challenges the current dogma that having two copies of APOE4 is a guaranteed risk for Alzheimer’s disease. The discovery highlights the potential of diet to modify genetic risk factors and suggests that healthy behaviors such as exercise, sleep, stress management, and nutrient-dense eating can significantly impact dementia risk.
Previous studies have linked Mediterranean and plant-based diets to reduced dementia risk, with some findings suggesting a 23% lower risk for those who followed the diet closely. A more recent study found that adding just one food category from either diet – such as vegetables or fruits – reduced amyloid buildup in the brain to a level similar to being about four years younger.
The study’s findings have sparked concerns about the potential loss of valuable data and research due to funding cuts, which could impact future studies and discoveries.
Source: https://edition.cnn.com/2025/08/25/health/mediterranean-diet-dementia-apoe4-wellness