New research suggests that spending a lot of time on “mentally passive” activities like watching TV or smartphone screens may increase the risk of developing dementia.
In contrast, activities that keep the brain active, such as solving crossword puzzles, may help protect against it.
During the study, the researchers followed participants for about eight years to see who developed Alzheimer’s disease or mild cognitive impairment, a condition that often occurs before dementia.
The participants also answered questions about how mentally active they were at different stages of life.
In childhood, this included things like being read to, reading books, having access to newspapers or atlases, and learning a foreign language.
In middle age, activities included having a library card, subscribing to magazines and visiting libraries or museums.
In later life, it involved reading, writing, playing games and having sources of income like pensions or Social Security.
Based on this information, the researchers gave each person a score that reflected how mentally active they had been throughout their life.
They found that people with higher scores were much less likely to develop Alzheimer’s disease or mild cognitive impairment, compared to those with lower scores.
The study also showed that people who stayed mentally active developed symptoms later in life.
On average, those with higher scores were diagnosed with Alzheimer’s at age 94, while those with lower scores were diagnosed around age 88.
Mild cognitive impairment also appeared about seven years later in the more mentally active group.
“Our findings suggest that cognitive health in later life is strongly influenced by lifelong exposure to intellectually stimulating environments,” said study author and Rush University Medical Center neuropsychologist Assist Prof Dr Andrea Zammit.
The study’s findings were published in Neurology, the medical journal of the American Academy of Neurology, in February (2026). – dpa
