Participating in ordinary tasks such as reading, listening to the radio and playing games like checkers and cards on a daily basis may stave off the memory-robbing illness Alzheimer's disease.

The findings are from a study of more than 800 Catholic nuns, priests and brothers 65 and older who are participating in the ongoing US-based Religious Orders Study.

In the study investigators found that people who participated most often in mentally challenging activities had a 47% lower risk of Alzheimer's disease. Those who participated a moderate amount had a 28% lower risk of the ailment compared with those who rarely participated.

The researchers looked at 7 common activities, including watching television; listening to the radio; reading newspapers, magazines and books; playing games, such as cards, checkers or crosswords or other puzzles; and going to museums.

The amount of time study participants spent doing each activity was measured on a five-point scale with the lowest level of activity (rated a "1") for participating in an activity once a year or less, and the highest (rated a "5") signifying daily or "about every day" participation.

The researchers found that a person's risk for developing Alzheimer's disease decreased by 33% for each one-point increase on the participation scale. During the 5-year study, 111 people developed Alzheimer's disease.

We are asked constantly about this use-it-or-lose-it approach to maintaining memory. This study provides important new evidence that there may be something to the notion of increased use of one's brain reduces the risk of Alzheimer's disease.

The most common form of dementia in the elderly, Alzheimer's now affects about 4 million Americans. The disease is marked by the formation of "plaques" and "tangles" in the brain, and researchers have identified a range of possible contributors to its onset.

JAMA February 13, 2002;287:742-748