Another study led by Florida Atlantic University's Christine E. Spadola demonstrated that drinking coffee has far less drag on sleep than nicotine or alcohol. The research, which involved input from Emory University, found "people who used nicotine and alcohol within four hours of going to bed felt the largest impact on their sleep cycle, even when controlling for age, gender, stress, and other factors."
Recent studies have also demonstrated that people who drink two or three cups of coffee per day live longer, and a 2010 study showed caffeine intake reduces errors among night-shift workers.
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That all sounds good, doesn't it? But now comes the "it's complicated" part. Coffee contains caffeine, and caffeine is a central nervous stimulant. That means it has a huge impact on your sleep patterns and even your heart rate. And like anything, lots of coffee can certainly become too much of a good thing.
There's some debate on whether the study that showed drinking more than six cups of coffee per day bumps up your risk of cardiovascular disease holds up. But even the authors of a conflicting study that said people who drank 25 cups a day didn't suffer heart issues recommend against indulging in those amounts, ever.
That leaves night shift nurses trying to balance the benefits of drinking coffee with the downsides of drinking too much. And when you work at night, you've got the extra considerations of messed up sleep-wake cues and a higher likelihood of trying to function with sleep deprivation.
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According to a position statement from the American Nursing Association reported in American Nurse Today, sleep disorders like insomnia are one of the many chronic medical conditions that can be exaggerated by shift work. "The negative effects of shift work arise primarily from circadian rhythm disruption, sleep deprivation, and impaired melatonin production," the ANA said. To combat this aspect of Shift Work Syndrome, it recommended that "shift workers can help adjust to their schedules by avoiding caffeine, nicotine, and alcohol intake for at least five hours before bedtime." Other research suggests limiting coffee to two or three cups per day for maximum health benefits.
There are other ways to make sure that coffee is a friend, not a foe, when you work nights. Jenny Askew, a cancer survivor and registered dietitian at Balance Fitness and Nutrition in Alpharetta commiserated with night shift nurses. "Night shifts are so hard I wouldn't dare tell you not to drink coffee," Askew noted. "But you may want to start thinking of coffee less in terms of 'How can I rev myself up?' and more in terms of 'How do I take care of myself?' You're taking care of other people so you need to feel good, not just stretch yourself to do far more than your body wants using coffee."
Here are her tips for getting the benefits of coffee without sabotaging your sleep or energy:
Treat your first cup like you would at any job. "If you need it to get going, drink and enjoy!" Askew encouraged. "A cup when you're just starting your shift is fine, just like it would be if you had any other job."
Limit end of shift coffee. Switch to water or at least a decaffeinated beverage in the last few hours of your shift, Askew recommended. "Treat it like any other job, only at a different time of day." Even though the rest of the world will be waking up as you leave work, your bedtime is coming right up.
Along with skipping caffeine for at least the four or five hours before bed, Askew cautioned night-shift nurses to cut out the screen time as bedtime draws near. Both tactics will help you get better sleep, even if you're trying to sleep in daylight hours. "Instead of thinking about whether you're drinking coffee, it's more helpful to focus on the sleep habits that are conducive to being well-rested," she said. "Getting six to eight hours of sleep is what's really essential."
Pack some nutrient-dense snacks. Part of taking care of you so you can take care of others is maintaining your energy levels. It all gets back to setting yourself to feel restored and energetic, versus trying to rev yourself up with caffeine when you're sleep-deprived and undernourished, Askew added.
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For night-shift nurses, nutrient-dense foods replenish your energy far more than a second, third or fourteenth cup of copy, she pointed out. "Those nurses stations are notoriously bad, with everyone always giving nurses lots of food and night shift being so tired. It's set up for sabotage. And nurses are one of those professions where it's so hard to even have time to eat," she added. "As much as you can, I would advise packing your own food for work if you're a night-shift nurse. I'm sure there are terrible things you could also be bringing from home, but in general, you're bound to have much healthier options with your own selections than you would at work, especially overnight."