Coffee and cola may keep teens alert during the school day, but according to a recent survey, the caffeine in these drinks interferes with nighttime sleep.
The survey, published in the January 2003 issue of Pediatrics, the journal of the American Academy of Pediatrics, looked at the daily intake of caffeinated drinks and the sleep patterns of over 200 seventh-through-ninth-graders over a two-week period.
Children who consumed more than 63 milligrams of caffeine a day -- equivalent to about one-half of a cup of coffee -- were found to sleep fewer hours, were more likely to wake during the night and tended to be sleepier during the day.
The study also found that caffeine consumption started increasing on Wednesday, peaked on Saturday, then declined -- partially supporting the hypothesis that caffeine was sometimes used to counteract daytime sleepiness from sleep lost on school nights.
The authors note that while soft-drink machines in schools seem welcome by students and are profitable to school boards, they may be interfering with the nighttime sleep of teenagers. The authors' conclusion? That caffeine has detectable ill effects on health, and that its availability to teens should be limited.
Based on a January 2003 press release from the American Academy of Pediatrics