I feel like I’m being drafted over and over to defend soda. You’re all killing me. But after yesterday’s column on diet soda, I can’t ignore this. From Reuters, “Soda drinking tied to kids’ behavior problems: study“:
After taking into account habits that may have influenced the results – such as how much TV the kids watched, how much candy they ate and their mother’s race and education – the researchers still found that drinking two or four or more servings of soda per day was tied to higher aggression scores.
Overall, kids who drank four or more servings of soda per day were twice as likely to destroy other people’s belongings, get into fights and physically attack people, compared to children who didn’t drink soda.
Soda drinkers also scored higher on scales measuring signs of withdrawal and attention problems, write the researchers in The Journal of Pediatrics.
Suglia said that although the increased aggressive behavior may not be noticeable for each child, it’s moving all kids closer to the scale’s clinical threshold.
“Furthermore, if they’re drinking this much soda, it’s probably taking away from other nutritional things the child could be eating,” she said.
From CNN, “Does soda make kids more violent“:
Yet another study is warning parents to limit soda consumption with children. While previous studies have linked soda consumption with higher rates of obesity, a study published in the journal Pediatrics, says it also causes aggressive, violent behavior in children as young as 5 years old…
Children who consumed at least four servings of soda per day were twice as likely than those who didn’t drink any soda to display aggressive violent behaviors – such as destroying other people’s belongings, starting physical fights and verbally attacking other children. The kids were also more likely to have trouble paying attention to instructions, and were more withdrawn socially compared to 5-year-olds who didn’t consume soda.
“There was a dose response,” said Shakira Suglia, study author and associate professor of epidemiology at Columbia University. “With every increase in soda consumption, we saw an increase in behavior problems. It was significant for kids who consumed as few as one serving of soda per day.”
The association was present after researchers adjusted for parenting styles, and socio-demographic factors such as how much violent television the children were exposed to, their sleep schedule, and candy consumption.
The study itself:
Objective: To examine soda consumption and aggressive behaviors, attention problems, and withdrawal behavior among 5-year-old children.
Study design: The Fragile Families and Child Wellbeing Study is a prospective birth cohort study that follows a sample of mother-child pairs from 20 large US cities. Mothers reported children’s behaviors using the Child Behavior Checklist at age 5 years and were asked to report how many servings of soda the child drinks on a typical day.
They took 2929 children and measured behavior scores as well as how much soda they drank. With respect to the aggression scores, which is where CNN got its'”violent” headline, they used a 100 point scale. Kids who drank no soda scored a 56 (+/- 8). Kids who drank one soda scored a 57 (+/- 8). Kids who drank two sodas scored a 58 (+/- 9). Kids who drank three sodas scored a 59 (+/- 9). Kids who drank four or more sodas scored a 62 (+/- 9). What does that mean? I have no idea. Neither do the people who wrote the manuscript:
“It’s a little hard to interpret it. It’s not quite clinically significant,” Shakira Suglia, of Columbia University’s Mailman School of Public Health in New York, told Reuters Health.
That’s because those scores don’t mean much in and of themselves. What’s a one point difference? No one knows. We only know, evidently, that 50 is “normal” and 65 is “a clinical marker of when children should be evaluated for a problem“. Moreover, once you adjust for everything (as they did in Table III), then there is no longer any significant difference between kids who drank 1 or zero sodas. There’s also no significant difference between kids who drank 3 and zero sodas. There’s a 3-point significant difference between those who drank 4 or more versus zero sodas, with the 95% CI going from 1 to 5.
The other finding that’s being touted is that kids who drink 4 or more sodas are “more than twice as likely to destroy things belonging to others (OR, 2.54; 95% CI 1.7-3.8).” But twice as likely is a relative thing. Did it go from 25% of kids to 50% of kids? Or did it go from 0.01% of kids to 0.02% of kids. I can’t tell you, because the “data [were] not shown in tables”.
Moreover, this is NOT AN RCT. You can’t prove causality. It could be that the 4% of kids who get four or more sodas a day (which is a lot in anyone’s book) could have bad parents,* and that’s the cause of their aggression. Or, it could be the caffeine they’re ingesting is getting to them, irrelevant of its delivery mechanism. Or, it could be that they’re bad kids, and the parents give them lots of soda to shut them up. I don’t know. But what I do know is that this study does not prove that soda causes violent behavior.
*In no way do I think kids with aggression problems have “bad” parents. I’m being provocative on purpose to illustrate that you just can’t know. Additionally, if it was caffeine, that would be good to know, but that’s a knock on caffeine, not “soda”.