How Long Before Bed Should You Actually Stop Drinking Caffeine?

As sleep expert and holistic psychiatrist Ellen Vora, M.D., previously explained to mbg, caffeine has a half-life of five to seven hours for most people, meaning it takes roughly six hours2 for your body to metabolize half of that cortisol-inducing caffeine—and another six hours to metabolize half of that.

"A cup of coffee at 9 a.m. is still lingering in your body at bedtime, and having a cup of coffee at 3 p.m. is effectively like drinking half a cup of coffee at 9 p.m.," she says, adding, "even a little bit of caffeine lingering in the body can disrupt the quality of your sleep."

In addition to that, research has shown caffeine doesn't actually make up for poor sleep, creating what Vora calls a vicious cycle of bad sleep, more caffeine consumption3, more bad sleep, and so on.

So, when should you actually cut the caffeine if you want to ensure you can fall asleep? Again, this will depend on the person, but according to one study that looked into caffeine intake zero, three, and six hours before bed, you'll want to stop sipping at least six hours prior to bedtime.

Still, the study authors write, "caffeine consumption even 6 hours before bedtime can have important disruptive effects on both objective and subjective measure of sleep" in some people, so the "at least" is important here.

We all metabolize caffeine differently, so blanket recommendations won't necessarily hold true for everyone. If caffeine consumption is affecting your sleep, your best bet is to keep it early in the day and limit the amount you drink, too.