Meike Vernooij, a professor in epidemiology and radiology at Erasmus University Medical Center in the Netherlands, and her colleagues wanted to see how diet might impact the brain. They asked more than 4,000 older people in the Netherlands (average age: 66) about what they ate and analyzed brain scans over 10 years.
People who ate healthier diets resembling the Mediterranean diet — rich in fruits, vegetables and healthy fats from sources like fish, and low in red meat — showed larger total brain volume. They also had more grey and white matter, which is a way of measuring the amount of nerve density in the brain. The area of the brain that’s responsible for processing memories, called the hippocampus, was also larger in people who ate healthier diets.
Vernooij and her team also analyzed the effect of individual foods and nutrients, and found that no single component of the diet was responsible for the apparent benefit. The combined effect of eating more fruits and vegetables, whole grains, nuts, dairy and fish seemed to contribute to larger brain volume.
While the study did not delve into whether diet could change brain volumes or affect brain function, Vernooij and Pauline Croll, a co-author on the paper and a PhD student in epidemiology and radiology at Erasmus, believe the findings could lead to new research on how diet could affect brain disorders. “I do think these results open up a lot of opportunities,” says Croll. “It’s already known that a healthy diet is associated with better brain health, and that it is protective against neurodegeneration. But to truly say that a good diet can lower the risk of dementia, we need larger studies and [longer] follow up.”