Switching to a Mediterranean diet can boost and preserve brain power in old age more effectively than a low-fat diet, researchers claim.

Just six years of eating like the Spanish and Italians could also lower an individual’s risk of developing dementia, a study reveals.

The diet enjoyed by countries in southern Europe has long been thought to combat heart disease and cancer because it is rich in fruit, vegetables, fish, nuts, whole grains and olive oil.

People in Mediterranean countries eat more fish, nuts, whole grains and olive oil, which combat heart disease
Rich in nutrients: People in Mediterranean countries eat more fish, nuts, whole grains and olive oil, which combat heart disease

But it is now thought to offer further benefits, such as improved brain function.

Those eating more olive oil or nuts gained higher scores when their memory, attention span and abstract thinking was tested, scientists found.

Their research involved 522 men and women aged between 55 and 80 regarded as being at a high risk of heart disease, either from type 2 diabetes or a combination of factors including blood pressure, cholesterol, obesity, family history and smoking.

Two groups were allocated a diet with either added olive oil or mixed nuts, while a third was told to follow low-fat nutrition that is normally recommended to prevent heart attacks and strokes.

A plate of various Italian olive oils
Brain power: Eating more olive oil or nuts helps with memory, attention span and abstract thinking

After an average of 6.5 years, they were assessed for signs of declining brain power using a range of mental tests. Of the 60 who developed signs of brain impairment – an early indicator of dementia – 23 had followed the low-fat regime, while 18 had taken olive oil and 19 were on the nut diet.

A further 35 people developed dementia – 17 of which were on the low fat diet, 12 on olive oil and six on nuts.

Those on Mediterranean  diets also achieved significantly higher average mental test scores compared with those on low fat meals.

The findings held true irrespective of factors such as age, family history of dementia, education, exercise levels, blood vessel health and depression.

The unspoken illness

Researchers from the University of Navarra, Spain, who published the findings online in the Journal of Neurology Neurosurgery and Psychiatry, claim it is the first long-term trial to look at the impact of the Mediterranean diet on brain power.

Study leader Professor Miguel Martinez-Gonzalez said: ‘Our findings support increasing evidence on the protective effects of the Mediterranean diet on cognitive function.’

Olive oil is known to contain omega-6 fats – ‘healthy’ polyunsaturates that can combat conditions such as heart disease and arthritis and help reduce blood pressure.

Other research has also linked olive oil to lower rates of the bone-weakening condition osteoporosis in the Mediterranean, where people also eat less red meat and dairy products, compared with northern Europe.

Source: Daily Mail, London, May 21, 2013