Approximately 4.5 million people in the United States currently have Alzheimer's, a number that is expected to climb as high as 16 million by 2050 as the baby boom generation ages. The risk of contracting Alzheimer's disease rises as we age, affecting 10 percent of people older than age 65 and 50 percent of individuals over age 85.

Although much progress has been made in the fields of Alzheimer's medication, Alzheimer's care and even Alzheimer's treatment, researchers have thus far been unable to pin down the elusive Alzheimer's cure.

The Alzheimer's Association speaks of two Alzheimer's research goals:

1. To prevent onset of the disease in those who are at risk but not yet afflicted;

2. To treat and delay progression of the disease in those who already have the symptoms.

While Alzheimer's disease treatment is surely an admirable goal, and one that we all need to support, focusing on Alzheimer's prevention may yield more immediate results.

Alzheimer's disease prevention tips provided by the Alzheimer's Assoc include staying mentally active, being socially involved and adopting a brain-healthy diet (a low-fat, low-cholesterol diet full of vegetables). Recent Alzheimer's disease research has also discovered a link between regular exercise and a decreased risk of contracting the illness.

"A study in Finland of 1,500 elderly people found that those who were obese in middle age were twice as likely to develop dementia when they got old as those who were of normal weight. For those who also had high cholesterol and high blood pressure in middle age, the risk of dementia was six times higher than those who were not affected" (source: Philadelphia (Reuters); Mon Jul 19, 3:42 PM ET; by Jon Hurdle).

Professor of neuroscience and psychiatry and at Harvard Medical School, Dr. Joseph T. Coyle states that regular mental and physical activity may help to improve the chances of Alzheimer's prevention: "Crossword puzzles are not bad for you, and they may actually help prevent the onset of dementia. So I would say get regular exercise?..and find a hobby that you enjoy that's intellectually challenging".

Yet another expert to weigh in on the Alzheimer's exercise link is Dr. Lawrence Whalley with the School of Medicine at Scotland's University of Aberdeen. "Basically, whatever's good for your heart is good for your head. Mortality of vascular disease in the United States was halved between 1965 and 1995, and this is one of the great public-health successes of the 20th century. And what people are looking for in dementia prevention is the same, because the factors that everyone knows predispose to heart disease also predispose to dementia".

If regular exercise can indeed help to prevent Alzheimer's disease, then how much exercise is needed? Less than you might think. Researchers from Sweden found that "?..those who, in their middle years, exercised during their free time at least twice a week were 60 percent less likely to develop Alzheimer's disease compared to sedentary men and women who exercised less than twice a week. The active individuals were also 50 percent less likely to develop other forms of dementia and memory loss" (source: alzinfo.org).

What the public needs to realize, however, is that just any old workout won't necessarily deliver the Alzheimer's preventing power they seek. In the Sweden study, for example, exercise was defined as physical activity lasting at least 20 to 30 minutes and intense enough to cause breathlessness and sweating. That's a far cry from the lightweight, low impact and effortless 'exercise' embraced by many weekend workout buffs.

The bottom line is that, while scientists still haven't identified an Alzheimer's cause or cure, the amount of Alzheimer's information we have available has given us some useful tools to help us prevent this dreaded disease. One such resource is regular exercise, which has been proven to reduce the risk of Alzheimer's disease in the majority of people.

While there is certainly no guarantee that consistent exercise, or any other treatment for that matter, will provide full Alzheimer's protection, it can be stated with certainty that those people who regularly engage in strenuous exercise will lower their risk of Alzheimer's. This fact, added to all the other myriad benefits of regular exercise, makes a strong case for joining a health club, gym or fitness center today.