Consuming the equivalent as a single cup of coffee per week could disturb children’s sleep and potentially harm their mental health, new findings suggest
According to research led by King’s College London, children aged nine to 11 who consumed caffeine, primarily nally smaller surface area across the outer layer of the brain
The study highlighted that those recording the highest intake of caffeine went on to experience increased mental health difficulties six months later
It comes as the government is set to ban the sale of high-caffeine energy drinks to under-16s in England
The legislation will come into force in April 2027 and will apply in shops, vending machines and also online
Academics at the Institute of Psychiatry, Psychology and Neuroscience at King’s analysed data covering 9,632 children participating in the US Adolescent Brain Cognitive Development (ABCD) Study
The research assessed weekly self-reported consumption of various caffeinated beverages, including tea, coffee and soft drinks
Parents submitted details regarding average sleep durations, while MRI scans assessed the thickness and surface area of the brain’s cortex—a key region governing memory, reasoning, learning, thinking and problem-solving
Participants subsequently completed self-reports on their mental health at six and 18-month checkpoints
Researchers found greater caffeine consumption was associated with lower surface area across the cortex, though as little as one caffeinated drink a week may have had an effect, compared with none
Dr Divyangana Rakesh, senior author of the study, said: “Caffeine is such a normal part of daily life that it’s easy to forget young people are consuming it too
“Studies have found that two-thirds of adolescents consume caffeine at least once a week
“Despite it being a psychoactive substance, it is completely unregulated
“We found that even fairly low levels of intake were linked to small differences in brain structure and later mental health, and lower sleep duration seems to be an important underlying link
“Although we cannot comment on causality, our results do suggest that both caffeine intake, including from soft drinks, and sleep are worth paying attention to when we think about young people’s mental health.”
Jiayi Zheng, first author of the study, said: “Soft drinks (can) contain a lot of sugar and often go hand in hand with less healthy lifestyle habits and more risk-taking behaviours, so we can’t yet separate the role of caffeine from everything else that comes with them
“That’s the next question we want to answer, ideally with more precise measures of what young people drink, when they drink it and how well they sleep.”
Derek Hill, professor of digital health at University College London (UCL), said the study only included brain imaging at a single timepoint and caution was needed over the findings on brain surface area
He also urged caution over the fact children and parents reported the findings on sleep duration and mental health, which may not be as reliable as assessments by a health professional for example
The forthcoming energy drink ban will apply to drinks, other than tea or coffee, containing more than 150mg of caffeine per litre
Public Health Minister, Sharon Hodgson, said: “High-caffeine energy drinks have no place in children’s hands. We know thousands of kids in England consume them daily but the evidence is clear that this can cause anxiety, affect their sleep and concentration and can have a detrimental impact on their education
“This ban will reduce children’s opportunity to buy drinks that are harmful to their health and wellbeing, and demonstrates our firm commitment to creating the healthiest generation of children ever.”
