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.