Children who drink fizzy drinks such as cola every day are more impulsive and have poorer memory, a study suggests.
New research has revealed the potential harmful effects that drinking caffeinated soft drinks can have on children as young as nine.
Experts analyzed more than 2,000 American children, aged between nine and ten, who were asked how often they drank Coke, Pepsi or Dr Pepper.
They were also given a series of tasks to complete while their brain activity was recorded. For example, in one task the children had to figure out whether an object presented to them was the same as what had been shown to them before.
New research has revealed the potential harmful effects that drinking caffeinated soft drinks can have on children as young as nine
Analysis, published in the journal Substance Use & Misuse, revealed that those who drank caffeinated soft drinks daily were more impulsive and had poorer working memory.
Having low working memory may mean that you have difficulty organizing or completing a multi-step task, missing details in instructions, or not keeping track of what you are doing.
Children who regularly drank caffeinated soda also showed marked brain activity compared to their non-drinking peers.
For example, when performing the impulse control task, daily drinkers showed lower activity in a brain region called the anterior cingulate cortex (ACC).
Decreased activity in the ACC is commonly observed in children with attention deficit hyperactivity disorder (ADHD) and in individuals with substance use disorders.
Meanwhile, in the working memory test, daily drinkers showed less activation in a brain region called the inferior frontal gyrus (IFG), which is part of the frontal lobe.
Previous studies have shown that reduced activation in the frontal cortex is associated with lower working memory capacity.
The researchers from Seoul National University also found that children who drank soda daily were twice as likely to try alcohol when a follow-up study took place a year later.
Lead author Mina Kwon said: ‘Our findings suggest that daily consumption of caffeinated soft drinks in children is predictive of substance use in the near future.
‘One possible explanation is that the substances in caffeinated soft drinks – caffeine and sugar – can cause a toxicological effect on the brain, making the individual more sensitive to the reinforcing effects of harder drugs such as alcohol.’
This idea is known as the ‘gateway hypothesis’, but the team said an alternative theory, the ‘common liability hypothesis’, is also possible.
The idea behind this theory is that children who are naturally less able to regulate their impulses are more likely to seek out and try substances such as caffeine at a young age.
As they get older and it becomes easier to access illegal substances, they may move on to harder drugs like alcohol.
Professor Woo-Young Ahn, who also worked on the study, said: ‘Regularly consuming caffeinated soft drinks may indicate a higher risk of starting substance use in the future, due to the common risk factors between the two behaviors.
‘Our results have important implications for public health recommendations, as our study provides new insight into the neurobehavioral correlates of caffeinated soft drink consumption in children, which has rarely been evaluated.
‘It is therefore critical to develop evidence-based recommendations for the consumption of caffeinated soft drinks in minors. There is no consensus on a safe dose of caffeine in children, and some children may be more vulnerable to the adverse effects associated with frequent caffeine consumption than others.”
The team said there is a “critical need” for further research to see if there is a pattern between the consumption of caffeinated soft drinks among nine- to 10-year-olds and their use of other harder substances as they get older.