A new study says that kids who are allowed to watch R-rated movies are much more likely to believe it's easy to get a cigarette than those who aren't allowed to watch such films. 

The researchers found that parental permission to watch R-rated movies was one of the strongest predictors of the perception that cigarettes are available, about as strong as having friends that smoked. If allowed to watch R-rated films, nonsmokers were almost twice as likely, and smokers were almost three times as likely to say it would be easy for them to get cigarettes. 

The researchers looked at data from the second Development and Assessment of Nicotine Dependence in Youth, a four-year study of 1246 sixth-grade students in Massachusetts who were interviewed 11 times from 2002 to 2006. Students were asked if they agreed or disagreed with the statement: "It would be easy for me to get a cigarette." They were also asked "Is anybody allowed to smoke inside your home?" and "How often do your parents let you watch movies or videos that are rated R?" 

"We don't know why this is so. It may have to do with a parenting style that is permissive of activities that are not age-appropriate. Or it may be an outcome of all the smoking scenes in R-rated movies," says lead author of the study Chyke Doubeni, PhD, with the University of Massachusetts Medical School.

"Parents need to be mindful about the movies their children watch for a variety of obvious reasons. This study points out one more reason for not allowing children to watch movies that are not appropriate for their age," added co-author Dr. Joseph DiFranza with the University of Massachusetts Medical School. 

The study also found that having a favorite tobacco advertisement was significantly associated with perceived accessibility, as was knowing the Joe Camel cartoon mascot for Camel cigarettes. Unsurprisingly, kids with parents who smoke or allow smoking in the home tended to think it would be very easy to obtain cigarettes. 

"This implies that parental smoking likely contributes to youth smoking through increased perceived accessibility," says Doubeni. "Parents need to understand that your kids are more likely to get cigarettes if you smoke, particularly if you smoke in the home or allow someone else to smoke in the home." 

The study appears in the February 21 issue of the American Journal of Preventive Medicine. 

The study was funded by the Substance Abuse Policy Research Program (SAPRP) of the Robert Wood Johnson Foundation. The Substance Abuse Policy Research Program funds research into policies related to alcohol, tobacco and illegal drugs.