And how to lower your chances of getting it.

Developing Alzheimer's or another form of dementia might seem inevitable, at least if you live long enough. Three in 10 people over the age of 85 and almost one in 10 people over 65 have dementia. Those numbers are certainly alarming, but there's actually a lot you can do to reduce your risk, says neurologist Dr David Perlmutter.

The key moves to make, says Perlmutter, are centered around living a healthy lifestyle. Although your genes very likely play an important role in whether or not you develop dementia—a constellation of symptoms that includes memory loss and difficulties speaking or writing coherently, recognising familiar people and places, and performing everyday tasks—taking good care of yourself (or not) is also crucial.

Here are 8 common mistakes to avoid if you're hoping to cut your risk of this dreaded disease.

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