The US researchers found that children who drank more soda were more likely to be aggressive, to have attention problems, to get into fights and to destroy other people’s belongings (Suglia et al., 2013).
Among the 5-year-olds, 43% consumed at least one soda per day and 4% had 4+ servings per day. Those consuming four or more sodas a day were twice as likely to be involved in bad behaviours as those who drank none.
Is soda causing bad behaviour?
Since the study was based on associations, it doesn’t necessarily tell us that drinking soft drinks caused the behavioural problems, but this study does support the possibility.
For example, you might think that drinking more soda was a signal that a child had a troubled background. And it was the troubled background that was the real cause of the behavioural problems.
The researchers found evidence against this possibility by measuring the following factors and taking them into account:
- socio-demographic factors,
- maternal depression,
- intimate partner violence,
- and paternal incarceration,
The link between drinking soda and behavioural problems persisted with these variables factored in.
One factor the authors didn’t control for, though, is blood sugar level. It may be that some children with lower blood sugar consume more soda, and it’s the lower blood sugar that causes the bad behaviour.
Nevertheless the link still needs explaining. So perhaps it is the soda after all, given that:
“Caffeine has been linked to insufficient sleep, nervousness and jitters, impulsivity, and risk-taking in children and adolescents, and a study of 9- to 12-year-old children in Brazil found that those with depression were more likely to consume caffeine.” (Suglia et al., 2013).
Apart from caffeine, the other possible causative factors in sodas are:
- high-fructose corn syrup,
- sodium benzoate, and
- phosphoric or citric acid.
Since sodas are hardly a healthy choice for children or adults–they have been associated with obesity, heart disease, asthma and more–it makes sense for parents to limit their intake for both physiological and psychological reasons.
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Image credit: Ally Mauro