# Alcohol: what the research actually says

Alcohol shortens the time it takes to fall asleep and damages nearly everything that happens afterwards.



## All studies

- **Acute effect of alcohol intake on cardiovascular autonomic regulation during the first hours of sleep in a large real-world sample of Finnish employees: observational study** — Pietilä J, Helander E, Korhonen I, Myllymäki T, Kujala UM, Lindholm H (2018), JMIR Mental Health 5(1):e23. In 4,098 people, even 'low' alcohol intake cut sleep HRV by ~9%; high intake by ~40%, more so in fit and young people.

- **Alcohol and sleep I: effects on normal sleep** — Ebrahim IO, Shapiro CM, Williams AJ, Fenwick PB (2013), Alcoholism: Clinical and Experimental Research 37(4):539–549. Alcohol shortens sleep onset but suppresses REM and fragments the second half of the night.

- **Sleep, sleepiness, and alcohol use** — Roehrs T, Roth T (2001), Alcohol Research & Health 25(2):101–109. Review: alcohol's sedative effect fades quickly and rebounds into lighter, more disrupted sleep.

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Educational summary of published research, not medical advice. Screening scores are not diagnoses. If a score is elevated or you feel unwell, talk to a clinician.

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