In fact, many researchers believed that free radicals, produced when the body burns oxygen to produce energy consumed in food, may be at cause. Free radicals are believed to damage brain cells by taking electrons away from the body's healthy molecules to balance themselves. A few 'free radicals' is not a problem.
IF there are too many free radicals, the 'oxidative damage' affects the brain causing AD symptoms (Healing with Nutrition Web site).
Other risk factors
Odle (2003) notes that if a person has a first-degree relative (parent, sibling) with AD, that person's relative risk of getting it is about 3.5, or that person is 3.5 times more likely than the rest of us to develop AD. When the number of first-degree relatives rises to two or more, the relative risk rises to about 7.5.
In addition, people with Down syndrome, who have an extra APP gene, which is located on the 21 chromosomes, also have an increased risk above that of the general population; it is set at about 2.5 (Odle, 2003).
Researchers also noted that less obvious risk factors exist, including hypertension (high blood pressure) which predisposes some people to AD and vascular dementia (Boustnie et al., 2003 and Kawas et al., 1999).
Another list of risk factors includes:
Lack of participation in meaningful mental activities (Shumaker 2003, Coyle 2003, Green et al. 2003).
Further, lack of education seems to double the risk of dementia in those over age 75. And traumatic events that lead to unconsciousness and/or hospitalization, as well as repeated head injuries, lead to a relative risk rating higher than 2 (Kawas 1999).
It is apparent that most current research is being done on genetic causes of AD; of course, as many researchers noted, environmental factors may cause genetic factors to 'turn on' and begin a disease process. In addition, there seems to be developing a complex of physical conditions involving genes, proteins and enzymes that is suggestive in ascertaining the likelihood that certain populations will experience AD.
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