Drinking lots of soda may increase the risk of violent behavior in teens, a new study suggests.
Teens in the study who drank more than five cans of non-diet soda per day were significantly more likely report behaving violently towards others, and more likely to report having carried a gun or knife in the past year, the researchers said.
The results held even after the researchers took into account other factors that have been linked to violent behavior, including age, alcohol and tobacco use, and the frequency of family dinners.
A link between junk-food and aggression has been proposed before. In 1979, U.S. lawyers successfully argued that a defendant accused of murder had a diminished capacity to understand his actions as a result of switching to a junk food diet, a legal precedent that became known as the "Twinkie Defense."
It's possible that the caffeine and sugar in the soda may directly affect teens' behavior, the researchers said. However, it's also possible that people who violent have a penchant for soda. Additional research is needed to find the exact reason for the link.
Soda and violence
Researchers from the University of Vermont analyzed survey responses from 1,878 teens from 22 public schools in Boston.
Teens were asked how many sodas they had consumed over the past week, and whether they had been violent towards their peers, their siblings or people they had dated, or if they had carried a gun or a knife in the past year.
The responses were divided into two groups: those who said they drank up to four cans over the preceding week (low consumption); and those how said they drank five or more (high consumption). Just under one in three (30 percent) respondents fell into the high consumption category.
The more soft drinks the teens consumed, the more likely they were to have reported violent behavior. For those teens who were heavy consumers of non-diet sodas, the probability of aggressive behavior was 9 to 15 percentage points higher than that of low consumers.
Just over 23 percent of those who said they drank one or no cans of soft drink a week carried a gun/knife, but just under 43 percent among those drinking 14 or more cans said that. The percentage of teens who reported perpetrating violence towards a partner rose from 15 percent, in those drinking one or no cans a week, to just short of 27 percent, among those drinking 14 or more.
It's possible that an underlying condition, such as low blood sugar, may result in both high soda consumption and aggressive behavior, the researchers said.
But even if soda consumption doesn't cause violent behavior, it may be a useful marker for aggressive, the researchers say.
The study is published in online today (Oct. 24) in the journal Injury Prevention.
Pass it on: High soda consumption is linked with aggression in teens.
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