Over 55 million people worldwide were living with dementia in 2020, and this number will almost double every 20 years, reaching 78 million in 2030 and 139 million in 2050. Alzheimer’s Disease International highlights a worrying trend that someone in the world develops dementia every 3 seconds.

While much of the increase will be in developing countries, where 60% of people with dementia live in low and middle-income countries (which will increase to 71% by by 2050), it is a worrying rising trend throughout the world.

According to a new study, engaging in a variety of intellectually stimulating activities throughout life, such as reading, writing and learning a language, is associated with a lower risk of Alzheimer’s disease and slower cognitive decline.

However, it is important to highlight that the study does not prove that lifelong learning decreases the risk of Alzheimer’s disease; it only shows an association.

Nonetheless, the study, which was published on February 11, 2026, in Neurology (the medical journal of the American Academy of Neurology), found that people with the highest amount of lifelong learning developed Alzheimer’s disease five years later and developed mild cognitive impairment seven years later than those with the lowest amount of lifelong learning.

“Our study looked at cognitive enrichment from childhood to later life, focusing on activities and resources that stimulate the mind,” said study author Andrea Zammit, PhD, of Rush University Medical Center in Chicago. “Our findings suggest that cognitive health in later life is strongly influenced by lifelong exposure to intellectually stimulating environments.”

The study involved 1,939 people with an average age of 80 who did not have dementia at the start of the study. They were followed for an average of eight years.

Participants completed surveys about cognitive activities and learning resources during three stages. Early enrichment, before age 18, included the frequency of being read to and reading books, access to newspapers and atlases in the home, and learning a foreign language for more than five years. Middle age enrichment included income level at age 40, household resources like magazine subscriptions, dictionaries and library cards and the frequency of activities like visiting a museum or library. Later life enrichment, starting at an average age of 80, included the frequency of reading, writing and playing games and total income from Social Security, retirement and other sources. The researchers then calculated enrichment scores for each participant.

During the study, 551 participants developed Alzheimer’s disease, and 719 participants developed mild cognitive impairment. With this, the researchers compared participants with the highest level of cognitive enrichment, the top 10%, with those with the lowest level of cognitive enrichment, the bottom 10%. Of those with the highest level of enrichment, 21% developed Alzheimer’s. Of those with the lowest level, 34% developed Alzheimer’s.

After adjusting for factors such as age, sex and education, the researchers found that higher scores in lifetime enrichment were associated with a 38% lower risk of Alzheimer’s disease and a 36% lower risk of mild cognitive impairment.

They found that people with the highest lifetime enrichment developed Alzheimer’s disease at an average age of 94, compared to age 88 for those with the lowest level of enrichment, over a five-year delay.

For mild cognitive impairment, researchers found that people with the highest lifetime enrichment developed mild cognitive impairment at an average age of 85, compared to age 78 for those with the lowest level of enrichment — a seven-year delay.

Researchers also looked at a smaller group of participants who died during the study and had autopsies. They found those with higher lifetime enrichment had better memory and thinking skills and slower decline prior to death, even when researchers accounted for early brain changes linked to Alzheimer’s, like the buildup of proteins called amyloid and tau.

“Our findings are encouraging, suggesting that consistently engaging in a variety of mentally stimulating activities throughout life may make a difference in cognition,” said Zammit. “Public investments that expand access to enriching environments, like libraries and early education programs designed to spark a lifelong love of learning, may help reduce the incidence of dementia.”

The report highlighted that a limitation of the study was that participants reported details about their early and midlife experiences later in life, so they may not have remembered everything accurately.