Teens who guzzle more than five cans of soft drinks a week are significantly more likely to be aggressive, from carrying a knife or a gun to inflicting violence on siblings and peers, according to new research published in the journal Injury Prevention.
"There may be a direct cause-and-effect-relationship, perhaps due to the sugar or caffeine content of soft drinks, or there may be other factors, unaccounted for in our analyses, that cause both high soft drink consumption and aggression," write the authors, who queried 1,878 teens aged 14 to 18 from 22 public schools in Boston, Massachusetts.
The teens were asked how many cans of carbonated, non-diet soft drinks they'd had over the past week. Teens who drank up to four cans were labelled "low consumption;" five or more cans was deemed "high consumption."
Researchers then asked the teenagers if they'd been violent towards peers, a sibling or a partner and if they'd carried a gun or knife in the past year.
Some 43 per cent of teens who drank 14 or more cans a week admitted to carrying a weapon, a 20 per cent increase from teens who drank one or no cans a week.
Some 27 per cent of the 14-can cohort acknowledged violence towards a partner, up from 15 per cent in those drinking one or no cans a week. Aggression towards peers also rose, from 35 per cent to more than 58 per cent, as did violence towards siblings, up from 25.4 per cent to 43 per cent.
Those who drank five or more soft drinks every week (this turned out to be less than one third of respondents) were also significantly more likely to have consumed alcohol and smoked at least once in the previous month.
The major limitation here, one critics point out and the study authors acknowledge themselves, is whether this is causation or correlation, as in, what else is happening in Johnny's life besides his 14-pop diet, and why is he subsisting on fizz anyway?
As Mike Daube, director of the Public Health Advocacy Institute, put it to ABC, "It's primarily telling us that people who are more likely to be violent come from backgrounds where their overall diet isn't very good."