It is never too late to start eating a Mediterranean diet.
Research shows that consuming plenty of fruit and vegetables, olive oil, and even the odd glass of wine could slow shrinking of the brain among people in their 70s.
The study found that for pensioners on the diet, brain shrinkage - which is associated with memory loss and Alzheimer's disease - was less than half that of others their age.
The benefits are believed to come from the antioxidants in the diet, which is most closely associated with Italy. These are thought to reduce damage in the brain from oxidation, which leads to neural degeneration.
Lead author Dr Michelle Luciano, from the University of Edinburgh, said: "As we age, the brain shrinks and we lose brain cells which can affect learning and memory.
"This study adds to the body of evidence that suggests the Mediterranean diet has a positive impact on brain health." The latest study, published in the journal Neurology, looked at the dietary habits of almost 1,000 people in Scotland in their 70s.
A Mediterranean diet was judged as one high in fruit and vegetables, beans and grains, and the mono-unsaturated fats found in olive oil. It even allowed for drinking the equivalent of one large glass of wine a day for women or two for men.
People of this age would be expected to lose around 18ml of their brain volume in the three years between 73 and 76. But those found to have most closely stuck to a Mediterranean diet when questioned about it by researchers experienced less than half of that shrinkage, MRI brain scans showed.
More research is needed on which parts of the brain are protected, but brain shrinkage has been linked with dementia, backing up previous research that this diet, which is also low in meat and dairy products, could protect against Alzheimer's.