As a person ages, it’s normal to forget things like where you placed your wallet or car keys. When forgetfulness starts interfering with everyday life it could signal a bigger problem, though. Every 68 seconds an American develops Alzheimer’s disease; by the year 2050, that number is expected to rise to every 33 seconds, according to the March 2012 edition of Alzheimer’s and Dementia: The Journal of the Alzheimer’s Association.