Older adults who consume fish regularly are improving their brain health, a new study by Finnish researchers found.

Those studied who ate more fish were less likely to show certain brain infarcts-tiny areas of tissue that have died because of an insufficient blood supply-on an MRI scan, according to the study, which followed 3,660 adults age 65 and older. The tissue damage causes no obvious symptoms, but it can raise a person’s longer-term risk of having a stroke or developing dementia.

Those who ate tuna and “other” baked or broiled fish at least three times per week were one-quarter less likely than those who rarely ate fish to show the brain infarcts at the study’s start. They also tended to be less likely to develop new infarcts over the next five years. Positive benefits were not linked to the consumption of fried fish. Study results appeared in the journal Neurology. Omega-3 fatty acids, which are found in oily fish, are believed to have positive effects on the brain.