A 2003 study by Klinger, et al. tracked healthy people from middle age into their 80s. As part of the project, researchers identified 1,200 healthy people between the ages of 70 and 80 whose mental abilities ranked in the top third compared to the general population in this age group. The researchers tracked these high performers for a decade and determined who among them tended to remain high-functioning. They identified three factors that distinguished these people from the others:

• They were more consistently physically active than the others. They took daily walks and other forms of exercise, for example.

• They remained mentally active. These are the people who, rather than parking in front of the TV, did the crossword puzzle every morning, browsed the library shelves regularly for new and interesting books, dabbled in hobbies and crafts, or played bridge three times per week.

• They had a personality quality some have termed “self-efficacy.” They met challenges with the confidence and desire to solve them, rather than being ground under the wheels of misfortune.

(Klinger, S. et al. MacArthur Studies of Successful Aging. J Clin Endocrinol Metab).