

The fastest-growing demographic of U.S. pot users are surprisingly not millennials.

That title actually goes to senior citizens. Between 2013 and 2014, the number of American marijuana users at the age of 55 and over have increased from 2.8 million to 4.3 million, CBS News reports.

Cannabis consumption is up 53 percent among the 55-and-over demographic, most likely as a safer alternative to prescription drugs. While seniors make up only 14 percent of the U.S. population, they use over 30 percent of the nation’s prescription drugs.

CBS News took to Oakland’s Harborside Health Center, where owner Steve DeAngelo believes that even more seniors should come around on cannabis.

“There’s [an] ironic, almost tragic phenomenon, which is that seniors, who are one of the groups who can most benefit from use of cannabis, are the single group which remains most opposed to reforming cannabis laws,” DeAngelo told CBS News.

DeAngelo and Harborside have been working on senior outreach for years now, as he believes they have the power to end cannabis prohibition since they vote, and are one of the few remaining groups that oppose legalization.

“We’ll see our grandmothers and our grandfathers and our great grandmothers and our great grandfathers benefiting from this substance and advocating that use. And, you know, who wants to fight with their grandmother and their grandfather?” DeAngelo said to CBS News.

Watch the CBS report below.