Nighttime Coffee Does Not Affect Sleep, Study Concludes

Coffee is the most popular drink in the world; so popular, in fact, that people drink it all day. Indeed, it is not just a morning beverage.  However, many have been concerned that having some coffee later in the day might upset sleep patterns.  Obviously, coffee has caffeine—a stimulant that many people appreciate in the morning—so it would make sense that coffee might make it hard to sleep. 

But the surprising results of a new study indicates that coffee actually may not be as detrimental to sleep as you might think.  As a matter of fact, drinking alcohol within fours of sleep is actually more disruptive than caffeine.  The study also found that nicotine—whether a cigarette or vape, etc—had a stronger link to insomnia than caffeine.

In terms of coffee, though, the researchers found there is actually no significant link with sleeplessness. 

Now it is important to recognize that the researchers involved with the study are from Florida Atlantic University, Harvard University, and Emory University, as well as Mississippi Medical Center.  It is also crucial to recognize that the study followed 785 African Americans for 14 years; and they chose this population because previous data indicates that American Americans appear to suffer sleep disorders like insomnia, sleep apnea, and other conditions related to sleep.  Most importantly, though, none of the people involved with the study have been diagnosed with a clinical sleep disorder.

For the study, every participant was instructed to wear a wrist-band sensor that monitors their sleep. They were also asked to track their own sleep observations in a journal, including data on their comfort level, physical well-being, diet, and whether they smoked or drank before bed. Even when controlling for age, gender, weight, stress, anxiety, stress, and other factors, they found that caffeine had the smallest effect on sleep. 

Florida University’s Dr. Christine Spadola comments, “This study represents one of the largest longitudinal examinations of the associations of evening use of alcohol, caffeine, and nicotine with objectively measured sleep outcomes.  A night with use of nicotine and/or alcohol within four hours of bedtime demonstrated worse sleep continuity than a night without.”

She makes sure to warrant, also, “We did not observe an association between ingestion of caffeine within four hours of bed with any of the sleep parameters.”