If I had to come up with a catchphrase for the average college student, what would it be?
"I'll have a large coffee, please."
While only 54% of Americans over the age of 18 drink coffee every day, one University of Kentucky study showed that more than 78% of college freshmen consume above the recommended amount of caffeine per day. I am one such student, often drinking coffee to the point that my right eye begins to twitch. My friends and family are always telling me not to ingest so much caffeine. Such advice has become a common trope nowadays: but how bad is this "bad habit" of mine?
"...78% of college freshmen consume above the recommended amount of caffeine per day."
My coffee intake could be negatively impacting my sleep simply because I am a morning person. Developing research shows that early risers are more likely to experience sleep disruption from caffeine consumption. One study had college students record their consumption and sleep habits for a week. Wrist devices were also administered to monitor their movements during sleep. Most of the students, being so sleep-deprived, were able to sleep relatively easily, regardless of their caffeine consumption. However, for those who woke up early in the mornings, the amount of caffeine in their bodies correlated to the number of periods of wakefulness they experienced during the night. The more caffeine they consumed, the more time they spent awake in bed. Late risers did not exhibit such a trend.
The timing of consumption is also crucial in analyzing caffeine's effect on sleep. Researchers at Henry Ford Hospital's Sleep & Research Center and Wayne State College of Medicine discovered that caffeine consumed as early as six hours before bedtime still significantly disrupts sleep. Participants who consumed caffeine at bedtime, three hours before, and six hours before all experienced a shorter night's sleep and diminished sleep quality. They spent more time awake during the night. Even caffeine ingested six hours before bedtime caused participants to lose more than an hour of total sleep time!
"The late-afternoon cup of coffee that the average college student picks up after class could in fact be the reason behind much of their sleeplessness, even though they may not feel its effects."
Yet, of all of these findings, one stood out in particular: people cannot correctly perceive how much their caffeine consumption is affecting their sleep. Participants reported disruptions in their sleep as a result of caffeine consumed at bedtime and three hours before, but not as a result of caffeine consumed six hours before. Their sleep monitors told a different story: caffeine consumed six hours before bedtime greatly affected their total sleep time and sleep efficiency. The late-afternoon cup of coffee that the average college student picks up after class could in fact be the reason behind much of their sleeplessness, even though they may not feel its effects.
So listen up, college students. You'll feel more awake during the day if you cut back on your caffeine consumption. Not drinking caffeine past 1 p.m. will greatly improve your sleep quality. So the next time you think about walking into Starbucks after a late-afternoon class, choose to prioritize sleep over caffeine.
This post is part of our series on sleep culture on college campuses. To join the conversation and share your own story, please email our Director of College Outreach Abby Williams directly at firstname.lastname@example.org. And you can find out here if the #SleepRevolution College Tour will be visiting your campus, and learn how you can get involved. If your college is not one of the colleges already on our tour and you want it to be, please get in touch with Abby.