She looked up at me and said, 'I know you.' I smiled. She studied my face for a few moments. Finally she said, 'Yes, I know you. You're my son Billy!'

That was my mother about a month before she died. She was 85 years old. She had had Alzheimer disease, the most common cause of dementia.

The chances of having dementia rise as you get older. By age 85, about 35 out of 100 people have it1. After watching my mother I hoped I could figure out how to fit into the sixty five percent who grow old with a strong, active brain.

The Brain's Functions

The brain is your body's control center. It controls the autonomic nervous system, those automatic activities such as respiration, digestion, and heartbeat. It controls the somatic nervous system which activates your sense organs and muscles. It also controls conscious activities such as reasoning, abstraction, decision making and thought. It defines your characteristics and personality. Your brain controls every activity in your body.

As you age, your brain begins to function at a slower pace. It also takes longer to rejuvenate. Your lifestyle, as well as other external factors, will affect your brain's aging process. The good news is there are ways to enhance the power of your brain as time catches up with you. The following are four ways to help slow your brain's aging process.

1. Live a Healthy Life

The second most common cause of dementia is atherosclerosis, or in simple terms, hardening of the arteries in the brain. This is known as vascular dementia, accounting for as many as 40% of cases. Vascular dementia has been linked to high blood pressure, high cholesterol levels, heart disease, diabetes and related conditions. Most experts feel that treating these underlying conditions can decrease the odds of contracting vascular dementia or, if a person already has it, can slow its progress. These diseases are often accelerated by smoking, excessive drinking and both prescription and recreational drug use.

Smoking is bad for your health. It is also bad for your brain. A study conducted in the Netherlands followed 7,000 people age 55 and older for an average of seven years. During that time, 706 of the participants developed dementia. Smokers were found to be fifty percent more likely to develop dementia than people who had never smoked or had quit before participating in the study.

Alcohol abuse has been linked to15 to 25 percent of all dementia cases2. Alcohol affects the brain directly as a neurotoxin and is the cause of serious long term negative effects on the central nervous system. Alcohol abuse can lead to malnutrition, vitamin deficiencies and can also cause liver damage. Studies show that these can lead to brain shrinkage and brain damage.

Illegal drugs can also cause dementia. Cocaine affects circulation and has been shown to cause small strokes. Heroin, if taken for long periods of time or in older people, can block the neurotransmitter acetylcholine which is involved with learning and memory.

2. Eat Healthy Foods.

As a general rule, good nutrition for the body is also good for the brain. Healthy eating has been shown to reduce the risk of many chronic diseases such as diabetes, osteoporosis, cancer and heart disease. It also increases your chances of living a fuller, longer life.

To function properly your brain needs top quality fuel. A diet that includes five servings of fruits and vegetables a day, carbohydrates such as whole grain breads, pasta and cereals, as well as fats and protein can provide this for you.

Sometimes called brain food, fish is a rich source of unsaturated fat and protein. A study published in the Archives of Neurology3 found that eating fish at least once a week slowed down the development of dementia in elderly men and women. Overall mental function declined at a rate ten percent slower in these fish eaters when compared to peers who did not eat fish as often. Mental function in elderly men and women who ate fish two or more times a week declined at a rate thirteen percent slower than those who did not eat fish.

One final portion of a healthy diet that many people overlook is drinking plenty of fluids. A dehydrated brain doesn't think clearly. Remember, plain old water is the healthiest fluid you can drink.

3. Exercise Your Body

A study published in the Journal of the American Medical Association, consisting of 2257 Japanese-American men between 71 and 93 years old, reported that regular exercise can protect against the development of Alzheimer's disease. The research from a number of organizations including the Department of Veteran Affairs and the Pacific Health Research Institute, also suggests that it is better to exercise throughout your life rather than trying to make up for an unhealthy lifestyle in your later years.

Exercise helps us feel better both physically and emotionally. It can help improve our self image. It also improves our strength and endurance. It decreases body fat, improves movement to joints and muscles and increases the body's ability to process oxygen. Regular exercise helps reduce depression while reducing the risks of cardiovascular disease.

What kind of exercise program should you engage in? It depends on your particular likes and your body's physical condition. If you are over forty five and haven't exercised in a while, you should check with your doctor before beginning any type of exercise program.

Your exercise program should include both cardiovascular and strength building exercises. Cardiovascular exercises are good for your heart. These include walking, swimming, and bicycling and for best results should be done for at least thirty minutes a day, every day. Strength building exercises build your muscles while helping keep your bones dense, reducing the chance of osteoporosis. This can be anything from calisthenics to weight training.

A favorite exercise of mine is Tai Chi, a combination of slow, circular movements. A study by the Harvard Medical School showed that older women who practice Tai Chi regularly experienced a better fitness boost than walking briskly for three hours per week. The study pointed out that this was due to better oxygen utilization.

Tai Chi can help people suffering from arthritis and even osteoporosis. There is some evidence that indicates that the enhanced mind and body connection resulting from the practice of Tai chi can help protect against dementia and Alzheimer's disease.

Whether it's Tai Chi or any other type of exercise the most important thing is to just do it.

4. Reduce Stress

Stress increases your heart rate and blood pressure and can lead to stroke. There are two categories of stress. The first type, acute stress, is also known as the flight or fight reaction where the brain produces chemicals that tell the body to speed up, making it perform more effectively. This is the type of stress you'll experience when another car pulls out in front of you causing you to hit your brakes suddenly. This type of stress is normal and short-lived.

The second type of stress is known as chronic or long-term stress. This stress is abnormal and long lasting. There is strong evidence that this type of stress actually damages the brain. It occurs when we don't let go of stress. Chronic stress increases the release of stress hormones. Studies have shown that these stress hormones can actually kill nerve cells in animals and can probably do the same in humans.

One method of reducing chronic stress is through exercise. Stress can also be reduced through meditation. Another proven method is through hypnosis. Using the visualization process hypnosis can help a person learn to remain calm and relaxed even while experiencing an event that had been stressful to them in the past.

Whatever method of stress reduction you choose, it's important to remember that taking steps to reduce chronic stress will improve your overall health. It will also help you sustain your mental abilities.