Researchers from the University of Washington and the University of California claim that a glass of wine after work can help you sleep better. But there’s a catch: you need to have had coffee during the day.
Interestingly, this effect isn’t achieved if you’ve only consumed one of these beverages that day.
To avoid backlash from coffee and wine critics, the scientists noted that the best sleep is actually experienced by those who abstain from both drinks.
For those who enjoy coffee and wine, this study provides a great excuse to continue indulging. Now, they won’t have to deny themselves either drink throughout the day.
How the Study Was Conducted
It’s well-known that daytime coffee can make it harder to fall asleep at night. However, researchers have demonstrated that consuming alcohol at night can lead to longer sleep, partially offsetting the effects of caffeine. According to the scientists, daytime coffee and evening wine can counterbalance each other’s negative impacts.
To reach this conclusion, the team conducted a six-week study involving 17 healthy adult men. Each day, the volunteers consumed morning (daytime) coffee and evening wine, then answered questions about how long and well they slept, rating their sleep quality on a scale from 0 to 100.
During this period, the researchers found that each daily cup of coffee (or other caffeinated beverage) reduced the average amount of sleep by about 10 minutes per day (or an hour per week).
The results also indicated that each cup combined with a standard glass of wine shortened sleep by about five minutes per day (or half an hour per week).
Alcohol, which tends to enhance drowsiness, can thus partially negate the effects of coffee consumed during the day.
The researchers also found that each additional dose of alcohol per day (for example, a small glass of wine or half a pint of beer) led to more restless sleep at night, as reported by the participants.
However, when they also consumed caffeine that same day, their sleep quality improved, according to the Daily Mail.
The researchers believe that coffee may help mask daytime drowsiness caused by alcohol’s impact on sleep.
Key Takeaways
Frank Song, the lead researcher from the University of Washington, noted, “The interaction effect of alcohol and coffee turned out to be the opposite of what we expected.” He explained that the team observed people drinking coffee and alcohol in an attempt to “balance” their sleep.
“Indeed, consuming alcohol after coffee may ease the process of falling asleep,” added Frank Song. The downside is that alcohol suppresses an important phase of sleep, known as REM sleep, at the beginning of the night. Overall, as the scientist pointed out, “it’s better to avoid alcohol and caffeine.”
The team emphasized that the study only considered the duration and quality of sleep based on participants’ self-reports. Using sleep trackers might have altered the final results. The scientists also did not monitor when during the day the volunteers consumed coffee and alcohol. Therefore, they believe this topic requires further research.
The findings from this study were published in the journal PLOS One.