Neurologist Allan Bernstein exercises his brain these winter mornings by pruning his apple trees in Graton. That and an occasional game of tennis and "walking down the driveway to get the newspaper, and then again to get the mail, working in the chicken coop and walking the dog."

Exercise is essential to maintaining a healthy brain, said the brain doctor who is currently involved in a large Alzheimer's disease research study.

"Exercise lowers your blood pressure, protects the blood vessels," he said. "And going for a walk, doing something outside where you're also getting Vitamin D, is better than getting on a StairMaster and watching TV."

A popular international lecturer on brain health and a regular speaker with the Osher Lifelong Learning Institute at Sonoma State University, Bernstein is sympathetic to brain worries, especially among baby boomers and beyond.

Blank on the name of a neighbor and you think Alzheimer's. Forget the security code for your bike lock, the name of your dog's vet, you think Alzheimer's.

Starts in 50s

"It's an age-related phenomenon," Bernstein said.

"It usually starts in your 50s, when you can't get a word or a name. It's when you say, wait a minute, what's wrong with me?"

"Most of that comes from overload," Bernstein said. The older you are, the more you've stuffed into your brain.

He does add, reassuringly, "Growing old doesn't necessarily mean you will develop memory loss. Normal aging is that you maintain all your mental faculties."

Alzheimer's disease, which causes brain cells to malfunction and die, is far more dramatic and destructive than occasional memory loss, but it's still "a big scary thing," said Bernstein, who is 69 and whose father had Alzheimer's disease.

"It's what cancer used to be," he said, noting that President Ronald Reagan, "who looked like a strong healthy guy" and was formally diagnosed with the brain disease in 1994, "brought Alzheimer's to everyone's attention."

Retired after 34 years with Kaiser Permanente, including as chief of neurology at Kaiser Santa Rosa, Bernstein has continued to focus on brain research.

Currently, he's conducting a trial on early dementia and stabilizing memory at the Redwood Regional Medical Group in Santa Rosa, one of 20 trial sites worldwide.

Memory care hints

Because of his research work, due to wind up this summer, he's put on hold a lecture schedule he used to maintain, but offered some personal and professional hints on brain and memory care.

Avoid strokes: "Watch your blood pressure and stroke risks carefully. Memory loss is a big issue with strokes."

Live healthy: A good basic rule, he said, is what's good for the heart is good for the brain. "Exercise. Keep your weight down. Eat a low-fat diet."

Consider vitamins: He believes he gets all he needs in his food — hie wife, Laura, a retired emergency doctor, grows most of their produce — but thinks the B vitamin group is important to brain health, as are vitamins D and E.

Get your sleep: "A good sleep allows our memory circuits to work properly."

Be social: "If you don't interact with people, you'll lose it. Social interaction stimulates learning more than doing it on your own. Reading a book at home is not as good as reading and discussing it at a book club."

Pay attention: "We have a flurry of things going through our brains at all times, often unrelated. If I'm thinking about my meeting tonight and someone introduces themselves to me during the afternoon, I'll probably forget their name. If I consciously pay attention, I'll remember."

De-stress: "High stress is bad for the brain," said Bernstein, who goes back to tree pruning as a favorite way to restore inner calm. That and fly fishing.

Avoid some drugs: Antihistamines, he said, slow the brain for up to 24 hours. "They may be good for a drippy nose, but the brain loses two IQ points for the day."

Advil and aspirin are OK, he said, because they can prevent blood clots and reduce stroke risks.

When his hip starts to ache from orchard work, he takes "one Advil and a glass of white wine."

Watch the alcohol intake: He follows the theory that "one drink is good for the heart and good for the brain, two drinks are neutral, and anything more impairs both."

Treat depression: "Depression causes memory loss. You don't remember what you had for breakfast because you don't care."

Avoid trauma: Referring to the link between athletes' head injuries and early dementia, Bernstein said, "Don't play football. Worse is boxing. Getting dinged in the head when you're 13 is not good for you at 45."

Remain open to new discoveries: "There is never an absolute answer," said Bernstein, "especially on medical topics."

Susan Swartz is a freelance writer and author based in Sonoma County. Contact her at susan@juicytomatoes.com.