Mediterranean Diet Cuts Dementia Risk, Regardless of Genetic Risk

March 14, 2023 – Sticking closely to the Mediterranean diet – rich in healthy fruits, vegetables, nuts, whole grains, and seafood – may help protect the aging brain.

In a large study of older adults, close following of a Mediterranean diet was tied to a 23% lower risk of getting dementia over an average of 9 years. 

This was true even in people with genes that make them more likely to have dementia, study investigator Oliver Shannon, PhD, with Newcastle University, Newcastle Upon Tyne, U.K., tells WebMD. 

The study was published online March 14 in the journal BMC Medicine. 

Diet may be an important risk factor for dementia. Focusing on diet, and eating healthier, could be targeted to prevent or cut the risk of the memory-robbing disease. Yet, prior studies exploring the impact of the Mediterranean diet have typically been limited in size, and few have explored the impact of one’s genetic makeup. 

In the new study, researchers looked at genetic and dietary data for more than 60,000 adults in the United Kingdom who were 60 and older. Over the course of about 9 years, 882 got dementia.

People who ate mostly the Mediterranean diet had a 23% lower risk of dementia, compared to peers who were least careful about following the diet plan. Sticking closely to the largely plant-based diet was equal to a 0.55% reduction in risk of getting dementia. 

This was the case regardless of a person’s individual genetic risk profile. 

“This is one of the largest studies in this area to date and, importantly, we found that even for those with higher genetic risk, having a more Mediterranean-like diet reduced the likelihood of developing dementia,” Shannon says. 

In a statement, Susan Mitchell, PhD, with Alzheimer’s Research UK, who was not involved in the study, said there is a “wealth of evidence that eating a healthy, balanced diet can help reduce the risk of cognitive decline. But evidence for specific diets is much less clear cut.”

“This new, large study adds to this overall picture, but it only drew on data from people with white, British or Irish ancestry,” she said.

“More research is needed to build on its intriguing findings, and uncover whether these reported benefits also translate to minority communities, where historically dementia has often been misunderstood and highly stigmatized, and where awareness of how people can reduce their risk is low,” Mitchell said. 

The new study adds to research published earlier this month, which found that people who most closely followed the Mediterranean diet or the brain-focused MIND diet had fewer signs of the hallmarks of Alzheimer’s disease in their brain after they died.