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PREVENTION

CAN ALZHEIMER'S DISEASE BE PREVENTED?

Please click on one of the subjects below for more more information about that subject.

General Information

Activity Patterns

Calorie Intake

Depression

Electromagnetic Fields

Exercise

Fluorescent Light

Social Activity

Solvents

Stress

Scientific References


GENERAL INFORMATION
    Can we prevent alzheimer's disease? I am optimistic about this, for varied reasons. Only a small number of alzheimer cases are caused by dominant genes that inexorably lead to alzheimer's disease.
    Numerous risk factors in the enviroment can increase or decrease the risk of getting alzheimer's disease. And many of these factors can be identified and modified. The rest of this section will discuss important risk factors that can be controlled and reduced.

ACTIVITY PATTERNS
    Several studies have found that low levels of physical and mental activity significantly increase the risk of alzheimer's disease [1-3]. A study in Japan finds that elderly with a great deal of "spare time" have a four-fold higher risk of alzheimer's disease [4]. A study completed in 2001 shows that people who have lower than normal activity levels in midlife, have an almost four-fold higher incidence of alzheimer's disease [5]. On the other hand, high activity levels seem to decrease alzheimer risk. A study in France of more than 2,000 elderly over the age of 65, finds that those who engage in traveling, odd jobs,knitting, or gardening have a lower risk of alzheimer's disease [6]. Interestingly, when lab animals are raised with environmental enrichment- many activities- their brain cells are more resistant to various insults [7]. The lesson here seems to be that you should maintain as many challenging activities as you can, for as long as you can, if you wish to keep your brain at optimum function.

CALORIE INTAKE
    A very recent study now suggests that those who overeat may put themselves at risk for alzheimer's disease. This study followed more than 2,000 non-demented elderly for as long as four years. The number of daily calories consumed at baseline was measured. Those elderly who consumed more than 1366 kilocalories a day at baseline tended to develop alzheimer's disease, whereas, those elderly who consumed 1240 or less kilocalories daily, did not develop alzheimer's disease [8]. The lesson here is not to restrict your intake to such low daily caloric levels, but to try to restrict your calorie intake to sensible levels that keep your weight at "ideal" levels, if possible.

DEPRESSION
    Feelings of depression and worthlessness seem to be a major risk factor for alzheimer's disease. In fact, episodes of severe depression precede the onset of alzheimer's disease [9-10]. Women with depression late in life seem especially vulnerable to alzheimer's disease [11]. Depression that occurs even 10 years before the onset of alzheimer's dementia, increases the risk of developing alzheimer's disease more than 2-fold [12]. Depression, combined with a family history of alzheimer's disease, increases the risk of the disease more than 7-fold above normal [13]. Some researchers feel that depression may be the earliest sign of the disease. One researcher found that 72 percent of alzheimer patients showed depression and social withdrawal up to 24 months before they were first diagnosed with the illness [14]. Thus, one way to prevent alzheimer's may be to avoid depression. Learn to "let it go" and also let your anger go. Holding in anger is one cause of depression.

ELECTROMAGNETIC FIELDS
    Electromagnetic fields have been linked to alzheimer's disease, although not strongly. Computers, television sets, electric heating blankets, and other electrical devices in the home emit magnetic fields that can disrupt the delicate balance of neurochemistry at the cellular level. One study of 326 alzheimer patients found that workers with exposure to electromagnetic fields seemed to develop alzheimer's disease more often [15]. One study of 130,420 deaths from 1982 to 1991 shows that alzheimer's disease clusters among electrical workers such as welders and utility workers [16]. Another study found that alzheimer's risk is high among seamstresses, dressmakers, and tailors, where heavy industrial machinery emits magnetic fields [17]. Electromagnetic fields can disrupt learning and memory in animals [18]. Two recent studies failed to find any evidence that electromagnetic fields increase alzheimer risk [19-20]. For the moment, there does not seem to be any solid evidence one way or another. In my view, I would avoid excessive exposure to magnetic fields, wherever possible, until this issue is settled by further study.

EXERCISE
    The Canadian Study of Health and Aging has followed more than 6400 elderly for more than 10 years. The group reports that people who engage in regular physical activity have 50 percent less risk of alzheimer's disease [23]. Exercise helps alzheimer patients, too. Although exercise does not increase cognitive ability in alzheimer patients, it does increase their alertness and balance [24].

FLOURESCENT LIGHT
    Regular fluorescent light may contribute to alzheimer's disease. Fluorescent light can cause the generation of hydrogen peroxide in solutions and, presumably, inside cells. Hydrogen peroxide is toxic to living cells. One study has found that skin cells from alzheimer patients are especially prone to damage when they are exposed to fluorescent light [21]. The blood of alzheimer patients seems to have less chemical defenses against free radicals, which can be generated by fluorescent light. One solution may be to switch to " full spectrum " lighting. Full spectrum lighting was popularized by John Ott. Full spectrum lighting includes more of the natural sunlight than is found in fluorescent. Further,full spectrum lights are shielded at the ends, to prevent the leakage of small amounts of x-rays. Studies have shown that children learn better under full spectrum lighting and that elderly prefer full spectrum to fluorescent because it is brighter and easier to read by [22]. Full spectrum lighting that fits in place of regular fluorescent is now available in many garden and craft shops. Full spectrum lighting also has the advantage that alzheimer patients exposed to it seem to sleep better and wander less at night.

SOCIAL ACTIVITY
    Maintaining a strong network of friends and social activities may help ward off alzheimer's disease. A loss of friends or social settings increases alzheimer risk [25]. In fact, one study reports that losing many friends increases the risk of alzheimer's disease more than 2-fold [26].An interesting example of how lifestyle influences alzheimer risk is a study of Japanese Americans. In Japan, there is a strong emphasis on family and friends. Japanese Americans who lived and spent time in Japan have less alzheimer risk than Japanese Americans who never lived in Japan,where they might have been exposed to more ties with family and friends [27]. The message seems pretty clear... as you age,try to keep close ties with family and friends. The payoff might be a life free of alzheimer's disease.

SOLVENTS
    Solvents could be a risk factor for alzheimer's disease. One study finds that industrial solvents do not increase alzheimer risk [28]. Two other studies,however,come to different conclusions. A 1995 study analyzed the records of a health maintainence organization in Seattle, Washington over a the five year period,1987-1992. The study reports that persons exposed to benzene, toluene, phenols ,or ketones, have a higher risk for alzheimer's disease [29]. The Canadian Study of Health and Aging, mentioned earlier, finds that workers exposed to glues, pesticides, and fertilizers are more likely to develop alzheimer's disease [30]. If you want to avoid alzheimer's disease, be careful when using solvents. Wear breathing masks and gloves and other rational safeguards as directed on the product label.

STRESS
    Stress is a very significant risk factor for alzheimer's disease. Why is stress such a "big deal" ? Simple. Stress of all kinds raises blood levels of a hormone called cortisol. Cortisol helps prepare our bodies for emergencies- it prepares us for fight or flight. The trouble begins when we get too much cortisol. Cortisol can actually kill brain cells. In fact, young,healthy college students start to suffer memory loss when their blood cortisol gets too high ; they can't recall paragraphs they just read [31]. Interestingly, in primates, elevated cortisol does not kill brain cells unless some sort of stress is also present [32].
   If stress can precipitate alzheimer's disease,then some of the major losses suffered by the aged should also increase risk. This is indeed the case. For example, retirement is a major stress event for most people. A recent study reports that retirement increases the risk of alzheimer's disease 5-fold [33]. Another major stress in the elderly is the loss of a lifelong spouse. Again, we find that being a widow or widower increases the risk of alzheimer's disease 2-fold [34].
    People with alzheimer's disease react more to stressful events than do non-demented elderly. For example, during stress induced by surgery, alzheimer patients show higher levels of blood cortisol [35]. The over-reaction to stress by alzheimer patients seems to be linked to higher blood cortisol, because numerous studies have found that alzheimer patients have higher levels of blood cortisol [36-38]. As alzheimer's disease becomes more severe, blood cortisol levels seem to get higher [39-40]. The high blood cortisol in alzheimer patients may intensify the loss of brain cells. Thus, one way to prevent alzheimer's disease may be to learn how to reduce stress in your life.

SCIENTIFIC REFERENCES


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