A prospective cohort study in American teenagers has investigated the association between non-cigarette tobacco use and subsequent cigarette smoking initiation.1 Ninety per cent of adult cigarette smokers acquire the habit before the age of 18 years. As non-cigarette tobacco use (e.g. e-cigarettes) increases, there are concerns that use among young people who have not previously smoked could lead to subsequent cigarette smoking.

The study included 10,384 young people aged between 12 and 17 years (mean age 14.3 years), who had never smoked a …