Some people retain their mental powers to a ripe old age. Others gradually lose their ability to remember and concentrate as they grow older. Why the difference?
While scientists still don't fully understand why some people are susceptible to degenerative brain disorders like Alzheimer's disease (AD), we do have some preliminary data. The risk of developing nerve tangles and brain plaques characteristic of AD seems to rise with increasing age, heredity, female gender, and chronic conditions like cardiovascular disease. A long chain of events involving inflammation and highly charged molecules called free radicals may also play a role in damaging the brain.
Due to a combination of factors, over four million people in the U.S. have AD. And the number is growing rapidly; by 2030, an estimated nine million Americans will be afflicted by this most-common form of dementia.
Fortunately, there is good evidence that you can help prevent or postpone the development of AD.
Lifelong Learning
We've long known that AD occurs less commonly in well-educated people. Ongoing studies suggest that regular mental stimulation — ;through work, continuing education, extensive reading, playing mentally challenging games, or learning a new language or musical instrument — ;can help keep your mental skills finely tuned.
How does it help?
Animal studies show that mentally stimulating activities cause brain cells to grow more numerous connections that aid communication with adjoining brain cells. And scientists have discovered that, even in old age, some areas of the brain can actually create new cells in response to stimulation.
Varied Activities
Participating in interesting social or leisure activities may diminish your risk of AD. In a study in Neurology, scientists asked 1,800 people over age 64 what they did in their free time. Researchers found those who engaged in the greatest variety of leisure activities — ;including hobbies, going on outings, visiting family or friends, volunteering, or joining in group social events — ;had the lowest risk of mental decline at the end of the seven-year study.
Physical Exercise
Staying physically active helps keep your cognitive abilities in good shape. Exercise enhances mental agility and alertness, perhaps by improving blood flow to the brain. It also reduces AD risk factors such as high blood pressure and hardening of the arteries.
In an eight-year study of exercise among 6,000 women, researchers found worsening mental abilities in 24% of those who walked a half-mile each week. But in women who walked the most — ;an average of 18 miles a week — ;only 17% showed signs of mental decline.
Stress Reduction
Excess levels of the stress hormone cortisol can damage the hippocampus, an area of the brain that shrinks in AD. You can reduce stress with techniques like meditation, yoga, and breathing or relaxation exercises. Getting the medical care you need for chronic stress, insomnia, depression, or other emotional problems may also help prevent AD.
Good Nutrition
A high-fat diet and obesity are factors that increase your risk for AD. Several nutrients that may offer protection include:
B-complex vitamins — ;especially folate, B6, and B12, found in multivitamins or leafy green vegetables — ;help reduce levels of a substance linked to AD called homocysteine
Monounsaturated fats such as olive oil
Omega-3 fatty acids in fish and flax seeds
Antioxidant vitamins C and E in fruits, vegetables, and whole grains
Preventing Brain Injury
Studies suggest that head injuries speed the onset of AD. Protect your head by wearing seat belts, bike helmets, and bright or reflective clothing. Also, avoid tobacco and excess alcohol since these substances can damage your memory. Preliminary research suggests that moderate drinking may be protective (no more than two drinks a day for men, or one drink for women).
Other Drugs
Daily low-dose aspirin may prove beneficial in preventin AD, but talk to your doctor about side effects. For people with high cholesterol, statin drugs may provide some protection against AD.
Controlling Chronic Conditions
Don't ignore sight or hearing problems. Wearing glasses or hearing aids may help prevent AD by improving your interaction with the world. Likewise, treatment of medical disorders like heart disease, diabetes, and high blood pressure or cholesterol reduces the chances they will damage your mind.
Overall, the best evidence I've seen indicates the way to avoid AD is to keep chronic ailments under control and stay physically, socially, and mentally active.
