Eating a healthy diet rich in veggies, fruit, nuts, and fish may help prevent brain shrinkage, according to a new study performed by Dutch researchers.

Snapshot of typical ingredients for a Mediterranean diet. Credit: Wikimedia Commons.

Meike W. Vernooij and colleagues at the Erasmus University Medical Center in Rotterdam surveyed 4,213 people in the Netherlands with an average age of 66 and no history of dementia. The participants self-reported their diet by completing a questionnaire asking how much they ate of nearly 400 items over the past month.

Based on the Dutch dietary guidelines, the researchers examined the quality of the diets based on the intake of the following food groups: vegetables, fruit, whole grain products, legumes, nuts, dairy, fish, tea, unsaturated fats and oils of total fats, red and processed meat, sugary beverages, alcohol and salt.

The quality of each person’s diet was ranked with a score of zero to 14. The average score was found to be seven, while the best diet consisted of vegetables, fruit, nuts, whole grains, dairy and fish, with a limited intake of sugary drinks.

To determine brain volume, the researchers scanned the brain of each participant with magnetic resonance imaging. Besides the brain scan, researchers gathered important information that could affect brain volumes, such as blood pressure, smoking history, and physical activity.

The average brain volume was 932 milliliters. After adjusting for age, sex, education, smoking and physical activity that a higher diet score was linked to larger total brain volume, when taking into account head size differences.

Those that consumed a healthy diet had an average of two milliliters more total brain volume than those who did not. According to the researchers, 3.6 milliliters less brain volume is equivalent to one year of aging.

It’s worth mention that diet was not linked to white matter lesions or small brain bleeds.

“People with greater brain volume have been shown in other studies to have better cognitive abilities, so initiatives that help improve diet quality may be a good strategy to maintain thinking skills in older adults,” said  Vernooij in a statement. “More research is needed to confirm these results and to examine the pathways through which diet can affect the brain.”

“There are many complex interactions that can occur across different food components and nutrients and according to our research, people who ate a combination of healthier foods had larger brain tissue volumes,” she added.

Findings appeared in the journal Neurology.