Background: Currently Australia does not have caffeine intake guidelines. Using 24-hr recall, the 2007 National Child Nutrition and Physical Activity Survey found that children 9-13y consumed on average 19.2mg caffeine/day. However, little is known about caffeine consumption and its impact on sleep in children. This study assessed caffeine consumption and sleep in school aged children.
Methods: Children aged 8-12y (10.7±1.3y, 49% male) were recruited through South Australian schools and the community for a retrospective, cross sectional study. Demographics, caffeine intake (a Food Frequency Questionnaire), and daytime sleepiness (Paediatric Daytime Sleepiness Scale) were obtained via child and parent report.
Results: Data from 230 children demonstrated daily caffeine intake ranged between 0–64.1mg (7.8±11.7mg). Gender did not impact caffeine intake (p=0.97). 74% of 8 year olds consumed caffeine (8.0±10.5mg), 78% of 9 years olds (8.3±9.6mg), 72% of 10 year olds (10.1±13.5mg), 83% of 11 year olds (9.7±13.4mg) and 87% of 12 year olds (12.6±13.2mg). 25% (n=58) of the sample consumed between 11.1mg (~Standard chocolate bar) and 64.1mg (~one small latte) of caffeine/day. Daily caffeine consumption had a significant relationship with age (r=0.14, p=0.03) and daytime sleepiness (r=0.14, p=0.03). Children who were in the top 25% of caffeine consumption had significantly higher daytime sleepiness compared to the remaining 75% of the sample, p=0.05.
Conclusion: These findings show that majority of children aged 8–12y consume caffeine. The study also shows a significant relationship between caffeine intake and daytime sleepiness in children, with greater caffeine consumption associated with more daytime sleepiness.