What affect does alcohol have on sleep?

Alcohol generally makes sleep more fragmented and less restorative, suppresses REM sleep, and disrupts the normal sequence of sleep stages. 1

• Nighttime awakenings: Alcohol can cause more awakenings—many too brief to remember—and you may wake feeling unrefreshed. 2
• Sleep stages and memory: It suppresses REM sleep and sleep spindles involved in moving memories to the cortex; alcohol can also disrupt the normal pattern of deeper sleep earlier and more REM later in the night. 3 4
• Timing: Alcohol consumed before sleep affects sleep until it has been metabolized, so drinking closer to bedtime can interfere with sleep. 5
• Regular use as a sleep aid: Alcohol may make you feel sedated and fall asleep faster, but sedation is not natural sleep; it fragments sleep and suppresses REM, undermining restorative sleep. 6