You now have one more excellent reason to shelve the store-bought dressing in favor of the homemade stuff: Eating a diet rich in extra-virgin olive oil may protect your brain as you age, researchers from Temple University suggest.

In the study, researchers genetically modified mice to express three key characteristics of Alzheimer’s disease: memory impairment, the buildup of sticky proteins called amyloid plaques, and tangles of tau proteins. Then, when the mice reached six months of age, they had some mice eat chow supplemented with extra-virgin olive for six months, while the others ate their regular food. This food change occurred before the mice began to exhibit signs of Alzheimer’s.

At nine months and 12 months of age, the ones fed extra-virgin olive oil performed significantly better on brain tests that measured working memory, spatial memory, and learning. They also showed a reduction in the formation of amyloid plaques and less of a substance associated with tangles—as well as greater connectivity between neurons in their brains—than the mice who ate regular food.

So how’s the healthy fat helping your brain? The researchers believe there are a couple mechanisms at play with extra-virgin olive oil.

Not only does the oil reduce inflammation in the brain, but it also triggers a process called autophagy, when your cells break down and clear out debris and toxins, the researchers explain in a release.

So if your cells are better able to clear out the bad stuff—which includes the amyloid plaques and tau protein tangles—they’re less likely to build up and contribute to nerve cell dysfunction that causes Alzheimer’s symptoms, they say.

Still, because the research was done on mice, it’s hard to say whether the same findings would apply to people. But there’s no harm in trying to tweak your diet to more of a Mediterranean one—of which extra-virgin olive oil is a key component. Following the diet has been linked to lower levels of depression and a reduction in cholesterol, for starters.