A study of 2,000 US children aged nine-10 found having these drinks daily was associated with increased impulsivity and worse memory. Analysis of brain scans by experts implied caffeinated drinks could make young individuals "more sensitive to the reinforcing effects of harder drugs like alcohol".
The researchers assessed how often children drank fizzy drinks containing caffeine or high-caffeine energy drinks, and how well they did in a series of tasks to measure brain development (including memory tests, concentration and impulsive control).
The young participants who drank caffeinated drinks every day performed far worse than those who did not have caffeine. Scans also showed differences in brain activity, with daily caffeine drinkers showing lower activity in the brain region called the anterior cingulate cortex, something that is also observed in children with ADHD and people addicted to drugs or alcohol.
The findings – published in the Substance Use & Misuse journal – also unearthed children who drank caffeinated drinks were more likely to try alcohol after one year. That said, scientists acknowledged they din't know for sure whether the caffeine caused the brain differences, or if children who are already naturally impulsive seek to drink more fizzy drinks.
"Our findings suggest that daily consumption of caffeinated soda in children is predictive of substance use in the near future. One possible explanation is that the substances contained in caffeinated soda [caffeine and sugar] could induce a toxicological effect on the brain, making the individual more sensitive to the reinforcing effects of harder drugs like alcohol," said lead author from Seoul National University Mina Kwon, The Times reports.
Co-author Professor Woo-Young Ahn added, "Frequently consuming caffeinated soda could indicate a higher risk of initiating substance use in the future, due to the common risk factors between the two behaviours.
"Our results have important implications for public health recommendations.
"It’s vital, therefore, to develop evidence-based recommendations for caffeinated soda consumption in minors. There is no consensus on a safe dose of caffeine in children, and some children might be more vulnerable to adverse effects associated with frequent caffeine consumption than others."
The team emphasised the need for more research to determine the link between caffeine consumption in children and future substance misuse, as well as strong guidelines for parents on how much caffeine is safe for children, and what the possible effects are, such as decreased concentration.
Current guidance on drinks for children
In light of the recent study, British Soft Drinks Association (BSDA) director general Gavin Partington said, "This study contains several significant limitations, as the authors themselves acknowledge. BSDA members do not market or promote energy drinks to under-16s, nor do they sample products with this age group. In addition, energy drinks carry an advisory note stating 'not recommended for children'.
"The BSDA Code of Practice on energy drinks was introduced by and for our members in 2010 and contains a number of stringent points on responsible marketing. We remain committed to supporting the responsible sale of energy drinks."
In terms of general drinks advice for babies and young children, while caffeine isn't mentioned specifically, the NHS has some guidance on what they should not consume (which includes drinks that typically contain caffeine).
"Squashes, flavoured milk, 'fruit' or 'juice' drinks and fizzy drinks are not suitable for young babies. They contain sugar and can cause tooth decay, even when diluted," the website states.
"For older babies and young children, these drinks can fill your child up so they're not hungry for healthier food. Instead, offer sips of water from a cup with meals. Fizzy drinks are acidic and can damage tooth enamel so they should not be given to babies and young children.
"Diet or reduced-sugar drinks are not recommended for babies and young children. Even low-calorie drinks and no-added-sugar drinks can encourage children to develop a sweet tooth."
Elsewhere, it adds, "Children should avoid sugary fizzy drinks, squash and juice drinks completely. Children who drink a lot of sugary drinks are more likely to become overweight."
In terms of hot drinks, it adds, "Tea and coffee are not suitable for babies or young children. If sugar is added, this can lead to tooth decay."
Meanwhile, the European Food Safety Authority (EFSA) suggests, "The single doses of caffeine considered to be of no concern for adults (3mg/kg bw per day) may also be applied to children, because the caffeine 'clearance rate' in children and adolescents is at least that of adults, and the studies available on the acute effects of caffeine on anxiety and behaviour in children and adolescents support this level.
"A safety level of 3mg/kg bw per day is also proposed for habitual caffeine consumption by children and adolescents."
However, the EFSA also acknowledges the main contributors to daily caffeine intake in all age groups are tea and coffee (not recommended by the NHS), chocolate and other non-alcoholic beverages.
Included in its Code of Practice, BDSA emphasises, "The Code states that high caffeine content soft drinks are not recommended for children, and specifies that this information should be clearly stated on the label of such drinks. It also states that high caffeine soft drinks should not be promoted or marketed to those aged under 16."
Meanwhile, the UK Government announced plans to ban sales of energy drinks to children in 2019 but have still not placed it into legislation.
The NHS advises the best drinks to give to children are water and milk (children should drink whole milk until they are two). As a general guide children should drink six-eight glasses of fluid each day.
For more information on drinks and cups for babies and young children, visit the health service's website. If you have any concerns or want advice, speak to your doctor about what is best for your child and their age.
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