Watching movie characters drink alcohol may increase the likelihood that an adolescent will engage in binge drinking, according to a pair of studies — one focusing on adolescents in six European countries and the other on American adolescents aged 10 to 14 who were followed for two years.

Both studies concluded that movies depicting alcohol use increased the likelihood adolescents watching them would go on to become binge drinkers, defined as having five or more drinks in a short period of time.

The research on European youth, published online on March 5 in the journal Pediatrics, included more than 16,500 students aged 10-19 in Germany, Iceland, Italy, the Netherlands, Poland and Scotland. An international team of researchers including from Dartmouth asked the students how often they'd had five or more drinks on an occasion and what popular movies they watched. In each country, they noted, most of the movies were "Hollywood blockbusters." Trained coders noted screen depictions of alcohol use. Correlation between the factors was then noted.

They found that 27 percent of the European youths had engaged in binge drinking, but that it varied greatly by country (6 percent in Iceland to 38 percent in the Netherlands). The teens who had seen more alcohol use in movies "were significanlty more likely to have egnaged in binge drinking," they said, even after controlling for factors like age, siocioeconomics and rebelliousness.

The researchers noted the finding held true "across cultures in countries with different norms regarding teen and adult alcohol use." Alcohol use, they pointed out, is not a factor in what rating a movie receives.

The cohort study of American adolescents, published in BMJ Open and led by researchers at Dartmouth, found that "limiting media and marketing exposure could help prevent both onset and progression" of teen drinking. It said that having friends who imbibed, watching films that portrayed alcohol use, having parents who drink and alcohol available at home, having alcohol-branded merchandise like T-shirts and being rebellious were all factors linked to alcohol use. Alcohol use by teens was also more likely as the teens got older.

The researchers suggested strategies for parents to reduce the risk that teens would drink. It said not to let booze-branded merchandise in the house and to secure alcohol so adolescents can't get it. It also noted the importance of not exposing children to alcohol use in media. The example parents set in regard to their own drinking matters a great deal as well, but that contributes to drinking in general, not specifically to an increased likelihood of binge drinking.

The researchers noted that product placement for cigarettes in movies is banned in the United States, but it is "legal and commonplace for the alcohol industry, with half of Hollywood films containing at least one alcohol brand appearance, regardless of film rating."

Over the course of the American study, alcohol use increased from 11 percent to 25 percent in the study subjects. An article by Dr. Vincent Iannelli on says that 42 percent of high school students in America say that they have had alcohol, while 24 percent claim to be binge drinkers.

The impact of alcohol on young, still-developing brains, is well documented by numerous studies. For example, NPR reported on 2010 research from the University of California San Diego published in Psychology of Addictive Behaviors that compared brain scans of teens who drank heavily and those that didn't. The scans showed damaged nerve tissue in the drinkers' brains. The scientists speculated that the particular damage they noted would impair boys' attention spans and the ability of girls to understand and interpret visual material.

Even before that, New York Times noted research that showed devastating effect on young brains from alcohol consumption: "Mounting research suggests that alcohol causes more damage to the developing brains of teenagers than was previously thought, injuring them significantly more than it does adult brains. The findings, though preliminary, have demolished the assumption that people can drink heavily for years before causing themselves significant neurological injury. And the research even suggests that early heavy drinking may undermine the precise neurological capacities needed to protect oneself from alcoholism."

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