Bridget Jones and The Matrix show people smoking

The experts at Bristol University who completed the study hope that their findings will prompt a change in film certification, so that under-18s are no longer exposed to such images.

The study looked at 360 top US box office films released between 2001 and 2005, including Bridget Jones, Spider-Man and The Matrix. Each of the films shows a character smoking.

The results showed that teenagers who had watched the films that included smoking were 73 per cent more likely to have tried a cigarette than those who hadn’t.

The study also looked at each of the participants’ social background and whether their parents or friends smoked.

However, even with these variables in consideration, the teenagers were still 32 per cent likely to have tried a cigarette.

Dr Andrea Waylen, who led the research, said, ‘We saw a linear relationship between adolescent smoking and the number of films they had seen depicting smoking.’

Dr Waylen believes that a film’s certification should be raised to 18 if they show scenes of smoking, then the UK would have lower youth smoking rates.

David Cooke, director of the BBFC, said, ‘Smoking is a major public health issue and we consulted the public very extensively on it in 2005 and 2009. Their clear expectation is that we should be vigilant, sensible and proportionate in how we deal with the issue.’

By Lauren King