Although there is no cure for Alzheimer's disease living a healthy lifestyle has been shown to reduce the risk of developing the condition. One of the ways to do this is by lowering cholesterol, something that can also be achieved with drugs called statins. A Dutch study by researchers at the Erasmus Medical Centre in Rotterdam studied 6,992 participants over 55 who were all free of dementia when they were examined between 1990 and 1993. The participants were followed up in 2005 by which point 582 of them had developed Alzheimer's. After taking into account social and demographic factors known to raise the risk of developing the condition statin users had a 43% decreased risk of Alzheimer's something that was true whichever kind of statin they took and whether or not they had a genetic variation which is known to raise the risk of Alzheimer's.
You can find out more about this study by clicking on the title of this post.