Can health campaigns make people ill? The iatrogenic potential of population-based cannabis prevention.

In the UK and elsewhere, social marketing is becoming a major feature of healthimprovement strategies. Based on marketing techniques developed for commercial sales, social marketing uses imagery (eg television, magazines, internet and billboards) and phrases (eg radio adverts and slogans) specifically aimed at target groups (eg young people), typically to increase their positive health behaviours. Both national organisations and local health services routinely develop such interventions, often with little evidence of specifically how each campaign will affect public health. In general, such campaigns are regarded as potentially beneficial and possibly ineffective, but rarely are they considered dangerous to health. However, with access to powerful media such as the internet, professional eye-catching graphics and demographic targeting techniques unimaginable only a decade ago, such views need reassessing. In this report, we highlight the potential for social marketing campaigns to have negative repercussions, using cannabis prevention as an example.