“I talked to a lot of older cannabis users when I researched my novel, Betty’s (Little Basement Garden). The average age of those who puffed or ingested cannabis was about 55 years old and while most of them were imbibing for medicinal purposes, there was a good percentage that enjoyed cannabis purely for recreational purposes. In fact, some of them liked it so much, they made a conscious choice to give up alcohol entirely in favor of the herb.”

http://www.huffingtonpost.com/laurel-dewey/marijuana-vs-alcohol_b_2110727.html