In the study, released in the Archives of Neurology, researchers analyzed diet information on 966 people, average age 72, who answered a food questionnaire to see how close they came to consuming a Mediterranean diet. The participants also underwent magnetic resonance imaging to measure white matter hyperintensity volume. White matter hyperintensity, according to the authors, is an indicator of small vessel damage. That damage can be part of the normal aging process but is also linked with risk factors such as high blood pressure, diabetes and smoking.
The consequences can be serious, increasing the chances of stroke and dementia in more serious cases.
Overall, researchers found that adhering more closely to a Mediterranean diet was associated with a lower incidence of white matter hyperintensity volume, and that remained after controlling for risk factors such as smoking, physical activity, high blood pressure and diabetes.

Among other findings: More men than women stuck to a Mediterranean diet, and those who were more physically active were also more apt to eat more foods associated with the diet.

While the results suggested that the ratio of monosaturated fat to saturated fat may be a key component in determining levels of white matter hyperintensity volume. However, the authors added that the overall diet, rather than specific pieces of it, may be more important.