In a new study of people over age 85, those who said they engaged in things like painting, quilting or book clubs during middle age were less likely to develop memory impairments that may precede dementia.

Based on these results, using your brain for cognitive and social activities seems to preserve cognitive function or keep the neurons stimulated, said lead author Rosebud O. Roberts of the Mayo Clinic in Rochester, Minnesota.

“What is surprising from our study is that you have to begin these activities in midlife and continue through old age,” Roberts told Reuters Health by email.

For the Mayo Clinic Study of Aging, 256 people ages 85 to 89 with normal cognitive function filled out questionnaires about their typical activities at age 50 and also during the year prior to study enrollment. Researchers extracted their health histories from medical records.

Every 15 months for roughly the next four years, the participants completed in-person mental status checkups with tests of memory, language, visual-spatial skills and executive function, which includes abilities like reasoning and problem-solving.

During the study, 121 of the 256 participants developed memory deficits that did not affect their daily functioning, but which may later progress into dementia, which is also called mild cognitive impairment.

Those who said they had engaged in arts, crafts like sculpting or woodworking, or social activities like Bible study or travel during midlife were about half as likely to develop mild cognitive impairment as those who did not, the authors report in the journal Neurology.

“In a sense, what the findings suggest is that such activities engage the brain in a way that keeps it ‘alive’,” Roberts said. “As you use your brain for these activities, we believe that you preserve or maintain function of the brain cells; you may also develop new neurons or neuronal connections that preserve memory and thinking skills.”

Physical exercise may help preserve brain function as well, she said.

“Continued education, learning new things - taking classes in a new area of learning, may also yield positive benefits for cognitive function,” she said.

Those who reported doing arts and crafts or using the computer in their 80s were also less likely than others to develop memory problems.

“For prevention of cognitive decline in old age, I would agree that people need to determine which cognitively stimulating activities they can maintain, and engage in these activities as early in life as possible, and not wait till they are older,” Roberts said. “People who are older can still gain benefit from these activities but the earlier people start and continue through late life, the stronger the benefits they are likely to reap from these activities.”

People with high blood pressure, depression and other chronic conditions were more likely to develop mild cognitive impairment, as has been found in other studies, according to Dr. James E. Galvin of NYU Langone Medical Center in New York, who wrote a commentary accompanying the new research.

“That was a confirmation of a lot of the things we already knew,” Galvin said. “What I thought was more interesting was to begin to look at something that reduced the risk. That’s what people want to know.”

Though this study only observed an association between cognitive activities and later memory, and did not test whether certain activities would directly preserve memory, people may begin to try new activities in midlife or later and there should be no downside to trying, Galvin told Reuters Health.

“The brain is an organ that while you can’t grow new brain cells, is constantly remodeling,” he said. “Doing something that’s stimulating, you build new brain connections and strengthen old connections.”

That can include developing old activities and picking up new ones, he said.

“If you have been knitting since you were 6, at some point it’s not a cognitively stimulating activity,” he said. “If you’ve never painted before, that is stimulating.”

But genetics and other factors play a role as well, and there is no guarantee that trying activities like knitting or book clubs will stave off cognitive decline for every individual, Galvin said.

“I know marathon-running vegan astrophysicists who develop Alzheimer’s Disease and Twinkie-eating couch potatoes who don’t,” he said. “There’s no guarantee.”