A late cup of coffee doesn’t affect your sleep as much as a cigarette before bed.
So tell me a new study published in the journal Sleep, which analyzed data from 785 African American men and women. And while nicotine and alcohol consumption four hours before bed were both associated with poorer sleep – even after controlling for factors like age, gender, and BMI – caffeine was not. not.
African Americans have been under-represented in research examining the effect of these substances on sleep, the report noted, even though they are more likely to experience short sleep duration and fragmented sleep than non-whites. Hispanics, as well as worse health consequences associated with poor sleep (including cardiovascular disease, diabetes, hypertension, and some cancers) compared to other racial and ethnic groups. This study aimed to fill that research gap, lead author Dr. Christine Spadola of Florida Atlantic University told MarketWatch.
“There is no reason to believe that these results cannot be generalized to other racial or ethnic groups,” she said. “This is one of the largest surveys on the impact of alcohol, caffeine and nicotine to date with over 5,000 nights of data.”
Dr Spadola (with collaborators from Harvard, Emory University, University of Mississippi, and Brigham and Women’s Hospital) worked with subjects who wore wristwatch-like sensors that tracked the quality of their sleep for an average of 6.7 nights (for a total of 5,163 nights of data). Subjects also kept sleep diaries in which they noted whether or not they had drunk alcoholic beverages (such as beer, wine, or hard liquor), caffeinated beverages (such as coffee, tea or soda) and / or smoked within four hours of departure. to sleep, although they did not track how much of each substance they consumed.
And good news for coffee and tea lovers: consuming caffeine in the hours before bedtime had no impact on how long it took subjects to fall asleep, how long they slept, or how long they slept. if they woke up during the night. Despite the oft-repeated recommendations not to consume caffeine in the hours before bedtime, caffeine affects different people in different ways. Some studies have also found that caffeine has no effect on sleep, or, the studies that did so were limited by small sample sizes that were not racially diverse. A 2012 study also found that night owls were not as affected by caffeine in the evening as early risers.
As for those who drink an after-work happy hour or sip wine with dinner, alcohol in the evening was linked to “a small but statistically significant reduction” in sleep efficiency (or the percentage of time spent asleep). in bed) and fragmented sleep. Research has shown that while most people think a nightcap helps them relax, alcohol is actually a nap killer. While this may seem to help people fall asleep faster at first, it reduces your body’s ability to fall asleep soundly, so you wake up without rest. Additionally, alcohol drinkers get up in the middle of the night to go to the bathroom more often because alcohol blocks the reabsorption of fluids in the body, which dehydrates you and fills your bladder faster at the same time.
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But the biggest sleep disorder in this study was nicotine, especially in subjects with insomnia. Insomniacs who smoked within four hours of bedtime were associated with just over 42 minutes less sleep, on average, compared to insomniacs who did not smoke. Smokers without sleep problems also woke up more frequently during the night (indicating an additional six minutes of waking up after falling asleep, or WASO) and had lower sleep efficiency than non-smokers.
Researchers wrote that this stems from the fact that nicotine is a stimulant, as well as the fact that the body experiences nicotine withdrawal while a person is sleeping, which disrupts their rest. Previous research has also linked nicotine consumption to difficulty falling asleep, lighter sleep, higher rates of obstructive sleep apnea and shorter sleep than those who do not use it. And of course, smoking is responsible for nearly 6 million deaths worldwide each year, According to the CDC, and is the leading cause of lung cancer.
Related:Smoking costs you over $ 27,000 a year. Here is your BS-free guide to quitting smoking for good.
The study did not ask how many cigarettes, cups of coffee, or servings of alcohol these men and women had consumed each night, so more research is needed to assess how the dosage of each substance affects sleep. And some caffeine-sensitive people may find that a late afternoon shot of java disrupts their sleep, so stick with what works for you.
More than a third of American adults sleep less than the recommended seven hours per night, According to the CDC. This costs the US economy $ 411 billion a year in lost productivity, and Americans spent $ 41 billion for sleeping pills in 2015, which is expected to reach $ 52 billion by next year.
For more tips on getting a more restless rest, these 4 sleep experts shared their own personal routines for catching Z’s.