Mediterranean diet may prevent memory loss and dementia, study finds

Eating more fruit, vegetables, whole grains, nuts and fish, while reducing red meat and dairy could be linked to better cognitive function in later life

Studies suggest that a Mediterranean diet, which is high in plants, fish and unsaturated fats, may reduce the risk of dementia (Getty Images/iStockphoto)

A Mediterranean diet, which typically involves more fish, olive oil, nuts, legumes and vegetables, is good for your brain and could lower the risk of developing dementia, a study has suggested.

Traditional Mediterranean diets are low in red meat and dairy, and are often associated with health benefits such as reducing the risk of diabetes, high blood pressure and cholesterol, and heart disease. Previous studies have also shown a link between the diet and longer life expectancy.

A new study, published in medical journal Neurology, suggests that the traditional foods in this specific diet may interfere with the buildup of two proteins, the abnormal buildup of which, is believed to contribute to Alzheimer’s-related brain changes

Research has found that the amyloid protein forms into clumps, known as plaques, between nerve cells in the brain and, if allowed to continue, can eventually allow a second protein, tau, to spread rapidly through regions of the brain involved in memory.

But according to the researchers at the German Centre for Neurodegenerative Diseases in Bonn, people who followed a Mediterranean diet closely showed fewer signs of amyloid and tau buildup compared to those who didn’t.

A total of 343 people at high risk of developing Alzheimer’s were examined as part of the study and compared to 169 cognitively normal subjects.

Researchers tested each person’s cognitive skills, including language and memory, and measured brain volume using scans. The spinal fluid from 226 participants were also collected and tested for amyloid and tau protein biomarkers.

The study found that for each point a participant lost on not following the Mediterranean diet, brain scans showed the brain aged an extra year in regions associated with Alzheimer’s.

It concluded that the findings were in line with other scientific studies that suggest the Mediterranean diet could be a “protective factor against memory decline”, adding that this could be explained by the decrease in amyloid and tau proteins present in people who adhered to the diet.

Postdoctoral fellow Tommaso Ballarini, who led the research, said: “These results add to the body of evidence that show what you eat may influence your memory skills later on.”

Researchers recommended that further studies should be carried out find out what it means for treating Alzheimer’s.

Previous studies have also showed a link between a Mediterranean diet and a reduced risk to losing brain function.

Last year, researchers from the National Eye Institute in Bethesda, Maryland, found that people who stuck more closely to a Mediterranean diet had a nearly “45 per cent to 50 per cent reduction in the risk of having an impaired cognitive function”.

Dr Emily Chew, lead author of that study, told CNN at the time that the risk of cognitive decline increased the more people failed to follow the diet - which involved eating more fruits, vegetables, whole grains, nuts and olive oil while reducing red meat and alcohol consumption.

She said: “Those who had the highest adherence to the diet had better protection than those who are in the second tier, who had more cognitive protection than those in the last tier.”