Understanding Alzheimer's Disease -- the Basics
What Causes Alzheimer's Disease? continued...
Another controversy centers on zinc, but its connection to Alzheimer's remains unclear. It is thought that at low levels zinc may be protective, but at higher doses it may be harmful. Yet, scientists remain unsure whether plaques cause Alzheimer's or are themselves a result of the disease. If the latter, zinc's ability to form plaques might be unrelated to what causes Alzheimer's disease in the first place.
There is some evidence that people with high blood pressure and high cholesterol have an increased chance of developing Alzheimer's. In a minority of cases, head trauma may be a contributing factor (the more severe the head injury, the greater the risk of Alzheimer's dementia later in life).
While many of these theories are still being studied, it is clear that the biggest risk factors associated with developing Alzheimer's disease are increasing age and family history.