Stay Upbeat, Active to Keep the Mind Young

June 25 -- WEDNESDAY, June 24 (HealthDay News) -- To stave off the mental decline associated with old age, engage in intellectually challenging activities, maintain a positive outlook and keep up your social life.

Those are the findings of what researchers say is the largest-ever review of studies on aging and the brain.

The review, which spanned three decades and covered more than 400 studies, found that remaining physically, mentally and socially active has a substantial impact on whether older adults experience declines in memory and cognition, which includes the ability to learn and solve problems.

"How people spend their lives does really have an impact on how they age cognitively," said study co-author Robert S. Wilson, a professor of neurological and behavioral sciences at Rush University Medical Center in Chicago. "The observational studies suggest people who are more intellectually active, socially integrated, physically active and who are relatively free from negative emotions like depression and anxiety all seem to be associated with aging better cognitively."

As the U.S. population ages, being able to keep mental decline at bay for even a little longer could have significant public health implications.

A hundred years ago, only about 4 percent of the U.S. population was older than 65. In 2000, that group reached more than 12 percent. By 2030, an estimated 20 percent will be older than 65.

Along with this, the prevalence of Alzheimer's disease is expected to quadruple over the next 40 years, Wilson said.

"There is going to be a huge burden of old people who are cognitively impaired," Wilson said. "If we can develop strategies that delay the onset of the disease by six months or a year or two, we can substantially reduce the human suffering and the cost of caring for them."

The study, which will appear in Psychological Science in the Public Interest, was released June 24 in Washington, D.C.