Build a brain reserve to ward off Alzheimer's

WASHINGTON — Exercise your brain. Nourish it well. And the earlier you start, the better.

That's the best advice doctors can yet offer to ward off Alzheimer's disease.

There's no guarantee. But more and more research shows that some fairly simple steps can truly lower your risk of the deadly dementia.

Also, if Alzheimer's strikes anyway, people who have followed this advice tend to do better — their brains withstand the attack longer before symptoms become obvious.

The goal: Build up what's called a "cognitive reserve."

"Cognitive reserve is not something you're born with," Dr. Yaakov Stern of Columbia University told a meeting of Alzheimer's researchers Monday. "It's something that changes and can be modified over time."

In fact, there's now enough research backing this theory that the Alzheimer's Association is offering free classes around the country to teach people — of any age, but especially baby boomers — just how to do it. They call it "maintain your brain."

"There is tremendous interest in making sure that by the time you're 80, your brain is there with you," explains California psychologist Elizabeth Edgerly, who leads the program.

A healthy brain weighs about 2 pounds, roughly the size of a cauliflower. Networks of blood vessels keep oxygen flowing to 100 billion brain cells.

Branch-like tentacles extend from the ends of those cells, the brain's own specialized wiring to communicate. Under a microscope, they look like bushy hairs. A healthy brain can continue to grow new neurons and rewire and adapt itself throughout old age — and you want your brain to be as bushy as possible.

That growth starts in childhood, when parents read to tots, and depends heavily on getting lots of education. The less educated have double the risk of getting Alzheimer's decades later than people with a college education. Likewise, people who are less educated and have a not-so-challenging job have three to four times the risk of getting Alzheimer's, Stern says.

If you're already 40, don't despair. What's the advice?

• Your brain is like a muscle — use it or lose it. Brain scans show that when people use their brains in unusual ways, more blood flows into different neural regions and new connections form. Do a new type of puzzle, learn to play chess, take a foreign language class or solve a vexing problem at work. Try to challenge your brain daily, Edgerly advises.