Pre-Bed Booze May Bust Rest

A nightcap may force the body to work harder at repair during sleep, making for a less restful night. Katherine Harmon reports

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People often turn to wine, beer or cocktails to unwind at the end of the day. These drinks might seem to be relaxing and to aid sleep. But research has shown that people who drink alcohol in the evenings actually get less REM sleep and have less restful nights.

Now a study demonstrates that late-night alcohol might decrease the amount of necessary overnight repair work that the body can do.

Subjects in the study drank strong, weak or alcohol-free beverages an hour-and-40-minutes before going to bed. The more booze the volunteers imbibed, the higher their overnight heart rate. These rapid beats were an indication that their bodies were not in the most productive rest mode, say the researchers. The work appears in the journal Alcoholism: Clinical & Experimental Research. [Yohei Sagawa et al., "Alcohol Has a Dose-Related Effect on Parasympathetic Nerve Activity During Sleep"]

The findings might help explain why those who frequently drink often suffer from insomnia at night and sleepiness during the day, as well as more long-term health effects.

So if you're looking for better, more healthful sleep, maybe avoid the nighttime nightcap.

—Katherine Harmon

[The above text is a transcript of this podcast.]

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