Your memory 5 ways to keep it sharp.(CR Health)

People usually start worrying about their memory when it starts to noticeably decline, often around age 50. Fortunately, normal lapses such as forgetting a name or misplacing your car keys don't necessarily mean you'll face serious cognitive deficits down the road. The brain is proving to be surprisingly resilient, capable of compensating for the assaults of aging. And simple lifestyle changes, such as more activity and better eating, appear to give the brain an almost immediate performance boost.

Here are five steps, based on the latest research, that can help preserve your memory:

Work out. Regular physical activity helps keep you sharp by protecting the cardiovascular system that feeds oxygen-rich blood to the brain. In a January 2006 study of about 1,700 older Seattle residents, simply walking at least three times a week cut the risk of developing dementia over the course of six years by nearly a third.

Choose an aerobic activity, such as brisk walking, biking, or dance aerobics, and gradually build up to at least 30 minutes all or most days of the week. Check with your doctor first if you have coronary risk factors, or before exercising vigorously if you're over age 50.

Stay connected. Close relationships with others might protect the mind by reducing stress and stimulating the brain. In a May 2006 study of 89 adults in their 80s, those with larger social networks showed virtually no decrease in cognitive ability, while those with smaller networks declined substantially.

Make time to see family or friends at least once a month. Consider volunteer work or joining a hobby or social club.

Exercise your brain. An active brain is a healthy brain: That's the finding of several recent clinical trials that have shown that memory training and other mental exercises can preserve or improve specific cognitive skills in older people.