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Alzheimer's Disease Health Center

Overview & Facts

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Facts conquer fear. Start here to find out what is and isn't known about Alzheimer's causes, Alzheimer's risks, and Alzheimer's prevention.

What Is Alzheimer's Disease?

Dementia is not a disease itself. It's a group of symptoms that are caused by various diseases or conditions. Read how dementia develops, what causes it, and which conditions are treatable.

People with dementia who "sundown" experience periods of increased confusion and agitation as the sun goes down -- and sometimes through the night.

The most common form of dementia among older people is Alzheimer’s disease. About 4.5 million Americans suffer from this condition, which usually begins after age 60.

Mental decline in Alzheimer’s disease shows up first as loss of memory function. Next to be affected are emotions and inhibitions. Brain lesions, called amyloid plaques and tangles, accumulate, causing a declining ability to cope with everyday life as brain cells die. Read more.


Several factors contribute to the development of Alzheimer’s disease. Family history is just one of them. Click here to see why scientists suspect that genetics may play a role in many AD cases.

Most scientists don't think aluminum -- from pans or other sources -- causes Alzheimer's disease. Here's a thoughtful discussion of this topic.

Are You at Risk?

The number of people with the disease doubles every 5 years beyond age 65. Are you at risk of Alzheimer's disease? Get the facts here.

People with Down Syndrome can experience premature aging.  Because of this, they’re at a higher risk for age-related health conditions like Alzheimer's. Click here.

Genes aren't destiny. But much of a person's risk for Alzheimer's disease is inherited. Click here to find out what researchers are learning.

Today’s obesity epidemic may be tomorrow’s Alzheimer’s epidemic. The high insulin levels seen in obese people may mean a high risk of Alzheimer's disease. People with diabetes are at a particularly high risk.

A risk factor gene already identified makes one form of a protein called apolipoprotein E (ApoE). Having this gene doesn’t mean you will definitely develop AD; it only increases the risk. Read more.


Leisure activities such as reading, playing board games, playing musical instruments, and dancing are associated with a reduced risk of dementia. Read more about brain fitness.

Our overall health habits can help reduce the risk of age-related illnesses. Here's what the National Institute on Aging has to say about preventing Alzheimer's disease.

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