The more often adolescents say they have seen adverts for e-cigarettes, the more often they use both e-cigarettes and smoke tobacco cigarettes, according to a study published in ERJ Open Research.

The study took place in Germany, where regulations around tobacco and e-cigarettes advertising are more permissive than in other parts of Europe. Elsewhere there are firm bans on advertising tobacco but certain types of adverts and promotions for e-cigarettes are permitted.