If you’re reading this while enjoying an afternoon coffee, you want to reconsider. Not the reading, but the sipping, as new research strengthens the case for avoiding caffeine too close to bedtime. While that might sound like common sense, what’s surprising is what length of time can qualify as “too close.”
Researchers had people take caffeine pills or a placebo on different days at bedtime, three hours before bedtime, and six hours before bedtime. The caffeine pills contained 400 milligrams of caffeine. By way of comparison, a grande 475mL coffee contains 330 milligrams of caffeine.
Regardless of when they took the caffeine, the study participants reported disturbed sleep. Even when they took caffeine six hours before bed, they lost more than an hour of sleep compared to when they took the placebo.
Everything else aside, missing sleep can compromise your running, because you won’t be able to recover as quickly from hard or long workouts. If you’re regularly dragging by mid-afternoon, you’re probably better off examining your morning and midday nutrition habits than taking a coffee break.
The research was published in the Journal of Clinical Sleep Medicine.