In the US, regular cannabis use is on a path to replace regular alcohol use among every age group 19 to 65. Just in time for Dry January, a massive, authoritative December 23 study, published in the journal Addiction, found young adults (those under 30) have set aside regular alcohol use in favor of rolling one up instead. Gen X has matching cohorts of regular drinkers and smokers. And even retirees are relinquishing more and more scotch for the indica.