Gerontologist and geriatric psychiatrist Dr. Robert Butler, founder and president of the International Longevity Center
"Throughout our life, we have to be intellectually stimulated and active physically," he says. It should begin long before it becomes critical, Butler adds.
Diet and exercise are key, he points out.
"We do have to have a healthy diet," Butler says. "For example, even atherosclerosis, which can cause strokes, is related to memory and intellectual function. So, you have to have a well-balanced diet: small, reasonable portions, and lots of fruits and vegetables."
Also, plenty of Omega 3s and other fatty acids, but "not the trans-fats you get in so many things."
Low folic acid levels could be another thing to watch out for, Butler observes: "We've know for a long time that, if you have low folates, or low folic acid, that that can relate to problems of intellectual function. That's been well known. The idea that you could have normal, healthy people take folic acid in doubling amounts might enhance memory function and cognitive ability, that's relatively new."
What about other dietary supplements you can buy in health food stores and elsewhere?
"Gingko Biloba may have some modest effect," Butler explains, "but the other ones are probably overrated. Most of the dietary supplements are probably overrated."
Exercise goes hand-in-hand with good nutrition, Butler says, "not only for circulation, but also neuro-agents such as endorphins that make a big difference in keeping the mind stimulated. For example, the 'runner's high.' There are a lot of things that happen in the brain that not only count for memory function, but intellectual function in general."
The exercise should be relatively intense, Butler comments: "A walk is better than nothing but, in truth, it's better maybe four or five days a week that you have 30 minutes of some reasonably sweat-producing activity."
Butler says cognitive vitality has been shown time and again to improve brain health. People can keep their minds active in a variety of ways such as book clubs, crosswords, political campaigns, or similar endeavors. It's a classic "use it or lose it" scenario, in which the brain can decline if you don't keep it active. An active and alert brain can combat depression and improve cognitive function.
Staying socially engaged helps, too: "You have to be socially engaged, intellectually active, perhaps learning a new language, for instance, but staying involved in ways that help your relationships with other people."