A handful of studies have suggested that activities such as reading, playing cards, and doing crossword puzzles help keep your brain sharp and may help prevent Alzheimer's disease—the most common form of dementia among older people. This latest study on the subject, published in the Journal of the American Medical Association , provides further evidence that cognitively stimulating activities may help reduce the risk of Alzheimer's disease in older people.

About the study

Researchers from Rush-Presbyterian-St. Luke's Medical Center in Chicago studied 801 Catholic nuns, priests, and brothers in the Religious Orders Study—a large, ongoing study of aging and Alzheimer's disease. Participants entered the study between January 1994 and July 2001. Upon entering the study, participants were at least 65 years old and were free of dementia based on an examination by a neurologist.

When participants entered the study, researchers measured their time spent on cognitively stimulating activities. Participants answered questions about how much time they spent on seven information-processing activities:

  • Viewing television
  • Listening to the radio
  • Reading newspapers
  • Reading magazines
  • Reading books
  • Playing games such as cards, checkers, and crossword and other puzzles
  • Going to museums

Participants rated their frequency of participation in these activities on a scale of 1 (once a year or less) to 5 (every day or nearly every day). Responses to each question were averaged to yield a composite score for participation in brain-stimulating activities.

In addition to the cognitive activity assessment at the start of the study, participants also underwent medical evaluation, including medical history, neurological exam, 20 tests of cognitive function, and review of brain scans, if available. They were also tested for an apolipoprotein E gene, which is a risk factor for Alzheimer's disease. With the exception of the gene test, the medical evaluation was repeated annually throughout the study.

After an average of 4.5 years of follow-up for each participant, researchers compared the cognitive activity levels of participants who developed Alzheimer's disease with the cognitive activity levels of those who did not.

The findings

People with the highest frequency of cognitive activity were at 47% lower risk of Alzheimer's disease than their counterparts with the lowest frequency of these same activities. For every 1-point increase on the 5-point cognitive activity scale, a participant's risk of Alzheimer's disease was reduced by 33%. This statistic remained the same regardless of age, sex, and whether or not the apolipoprotein E gene was present.

There are limitations to this study, however. First, participants were nuns, priests, and brothers, who are likely to have a different lifestyle than the general population of older persons. These findings may not apply to older people living different lifestyles. Second, because Alzheimer's disease is thought to develop slowly over many years, it's possible that the disease process had begun in some participants at the time they entered the study, but was not yet detected. If this was the case, lower cognitive activity scores could have been a reflection of the very early stages of the disease. Third, participants were required to recall and estimate their frequency of cognitive activity, which may have compromised the accuracy of their answers.

How does this affect you?

Will using your brain regularly as you age prevent Alzheimer's disease? It's too soon to say. But this study does add to a growing body of evidence that continuing to use your brain as you age may help ward off Alzheimer's disease. However, the study authors caution that more research is needed to understand the complex associations among cognitive activity, Alzheimer's disease, and cognitive function—not to mention genetic, biological, and environmental factors.

But since reading, playing cards, and doing crossword puzzles are enjoyable activities that keep the mind vital and active, there's certainly no downside. At the very minimum, you'll be engaged and occupied—and maybe reducing your risk of Alzheimer's disease at the same time.