The most common—and best known—form of dementia, Alzheimer’s disease afflicts more than 5 million people in the United States and more than 20 million more around the world, most of them over age 65. For a long time, the exact cause of Alzheimer’s disease was uncertain, but scientists have recently formed the clearest picture yet of exactly how the condition develops. What they found confirmed a hypothesis about the disease’s origins first proposed in the 1980s, but not demonstrated until recently. They learned plaques called beta-amyloids build up in the brain, clogging the neurotransmitters responsible for carrying signals within the brain and ultimately destroying brain tissue.
What creates this beta-amyloid plaque, however, is more mysterious. Scientists have long believed that the metal aluminum, was a contributing factor. However, while aluminum can be a neurotoxin in high enough dosages, there is no real evidence that it is a cause of Alzheimer’s disease. Research has not found any link Other researchers ave proposed a link between Alzheimer’s and diabetes, even going so far as to call Alzheimer’s disease "type 3 diabetes" because they have so many similarities, including risk factors and the ways both diseases affect the brain.
Personality is also linked with Alzheimer’s disease risk. In one study, neurotic people, particularly neurotic women, were found to be more at risk for dementia than more phlegmatic people. The decades-long study tracked a large group of women, determining, among other things, how much stress they had in their lives and how they were dealing with it. The women who had more trouble handling stress, who in personality tests had been evaluated as more neurotic, were more likely to have developed Alzheimer’s disease over the course of the study.
There is no cure for Alzheimer’s disease, and treatments can only slow, not stop, the decline, which is why it is important that people know what they can do to reduce risk. things like neuroticism are not east to consciously change, but other risk factors are manageable. Getting adequate exercise and paying attention to blood sugar can help prevent Alzheimer’s, just as they can diabetes. Head trauma can also lead to the disease, so people, particularly kids, in risky activities should wear helmets. Additionally, cholesterol can clog the brain just as it can the blood vessels.