American teens now smoke more pot than smoke cigarettes, according to the CDC’s National Risk Behavior Survey, which monitors health-risk behaviors like alcohol, tobacco, and drug use. It indicates that 23% of high school students have recently smoked pot, compared with the 18% that have smoked cigarettes. The number of smoking teens has been on the decline for years, but these stats mark the first time marijuana use has significantly exceeded cigarette use. Perhaps the switch-around is partly a question of publicity: warnings about the dangers of tobacco get ever starker, while cannabis use is increasingly accepted—one third of the total US population has at least tried pot, and a majority now backs legalization. American teens see marijuana as less unhealthy than cigarettes—although that belief is disputed by organizations such as the British Lung Foundation, which released a study this week claiming that one joint contains the carcinogenic equivalent of 20 cigarettes.