Marijuana Use Rising in br Young Adults, Study Shows.br The findings are based on the results of the br 2002-2016 National Survey on Drug Use and Health.br The American Academy of Pediatrics published an br article detailing the results of the study, which br examined marijuana and tobacco use amongbr 18 to 22-year-olds in the U.S. .br The survey found that exclusive br marijuana use in young adults br is increasing, particularly br among college students. .br The number of college students who br reported exclusively smoking marijuana over br the span of a month increased by nearly 8.br The study also found that exclusive br tobacco smokers decreased by almost br 16 over the 14 year span among br non-college individuals. .br Vaping was not explored in the study, br despite its growing usage among br young adults throughout the U.