You know you've been there: Your alarm starts blaring in the a.m., and with your brain consumed by a lethargy haze, you reflexively reach over and hit snooze, stealing yourself 10 more minutes of shuteye, then another 10 minutes, and then another. You probably have an inkling that relying on the snooze button so heavily isn’t doing your sleep quality any favors. But the damage you’re racking up and how it spills over and messes with your day might surprise you.

First, pressing snooze screws with your REM sleep. This is the most restorative sleep stage, crucial to feeling mentally focused the next day, said sleep specialist Michael Breus. It occurs just before you wake, and your alarm pulls you out of REM sleep. But hitting snooze and shutting your eyes again sends you right back into a new phase of it, which your brain stays in long after you’ve forced yourself to get up. The result: You’re foggy all day, and your productivity takes a dive.

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Another consequence is that your body clock gets out of whack, said Breus. The circadian rhythms that govern your internal timer want you to wake when the alarm sounds—the first time. Retreat back into sleep, however, and these rhythms get thrown off. Soon your body isn’t sure when to wind down and when to wake up. It’s a vicious cycle: You’re increasingly sleep deprived, so you rely more on the snooze button, but that just leaves you zombie-like day after day.

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So swear off hitting snooze, advised Breus. It’s a hard habit to break, but begin by investing in a new clock that doesn’t have a snooze setting, or just set your alarm for when you typically snooze to in the first place (so if you hit it then, you'll definitely be late).

Then, make a real effort to turn in earlier at night, which might mean sleep-proofing your bedroom so it’s easier for your body to doze off (these tips can get you started). Do it in half-hour increments until you find the bedtime that allows you to feel rested and ready to rise and shine…not slink back under the covers.

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