Medically reviewed by Susan Kerrigan, MD and Marianne Madsen

If sleep were a drug, it would be rightly celebrated as a miracle. Getting a good night’s sleep can improve your creativity, boost your immune system, and help you hit your diet goals. Over time, inadequate sleep has been linked to a host of health problems, including obesity and heart disease. Because lack of slumber increases the risk of infection, it makes the sleep deprived vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) –– the virus that causes COVID-19. So what is the connection, why are some virus survivors reporting insomnia, and does the sleep hormone melatonin provide protection?

Trouble Sleeping

Before the pandemic, inadequate sleep was rampant. In the United States, studies conducted by the American Academy of Sleep Medicine and Sleep Research Society suggest the “sweet spot” of healthy sleep for adults is seven to seven and one-half hours each night. For decades, growing numbers of people reported averaging less than six hours per night. This put them at a high risk not only for health issues but emotional ones as well. For the sleep deprived, a low-stress situation often feels like a high-stress one. In the United States, around 70 million people have at least one sleep disorder. As many as 80% of sleep disorders are undetected or undiagnosed. The U.S. is not alone. The wearable fitness tracker Fitbit recently labeled Japanese as the most sleep deprived, followed by Indians and Singaporeans. 

There has been some good news. Since 2004, studies show the average amount of sleep reported by respondents has been rising –– by around one minute a year. Sleep experts warn this is not enough. Blame for inadequate sleep has been laid at everything from our 24-hour entertainment options to late-night emails from employers to poor diet. Regardless of the cause, before the novel coronavirus arrived, insomnia was often described in pandemic terms. It’s a silent killer and a cumulative one –– it usually takes time before poor sleep takes its toll. However, its link to obesity in particular is part of a vicious cycle because overweight people often sleep poorly while those who are sleep deprived often crave the sorts of foods that contribute to weight gain. Worse, people with a body mass index over 30 are more likely to die from COVID-19 than those at a healthy weight –– one reason countries with higher percentages of obese people like the U.S. have also experienced a higher death toll. 

Extra ZZZZs

While enduring pandemic-motivated shut downs and stay-at-home orders, many discovered a newfound joy of sleep. Freed from a 9-to-5 schedule’s tyranny, more people were able to get their seven or eight hours despite post-midnight bedtimes. Studies have suggested the average person slept more in 2020 than they did in prior years. However, the sleep quality was often inferior, with more time needed to doze off and wakeful periods throughout the night.

Of course not everyone was as blessed. Even discounting the direct worries about getting the virus itself, millions more were impacted by closures that affected their income. Money worries are a main contributor to insomnia. Unfortunately, being tired might make you a target. That’s because lack of sleep weakens your cytokines. These disease-fighting proteins help your body fight infections and recover faster from illness. Vaccines also aren’t as effective in sleep-deprived people. Unfortunately, people of color are statistically more sleep deprived –– which may be one reason they suffer disproportionately from the virus. 

Sleep may also be an issue for those who have successfully battled COVD-19. Even those with mild symptoms have reported later issues with insomnia where prior to infection they didn’t suffer a sleep disorder. Research is ongoing. No one knows if “long COVID” is actually a physical complication or a psychological one. While battling a serious flu, younger people generally don’t worry that it could be fatal. Yet given all the coverage concerning the sudden unexpected progression of the illness in a few healthy people, it’s natural that those with the virus would have increased anxiety that their mild symptoms could suddenly become bad enough to require hospitalization. Afterward, survivors may have the sort of nightmare-inducing post-traumatic stress disorders seen in people who have lived through car crashes or witnessed acts of violence.

There’s another interesting sleep-related development. Researchers have consistently found that melatonin may protect against COVID-19. This naturally occurring hormone is partly responsible for our body’s sleep regulation. Although it’s too early to have a definitive answer, some patients have been given melatonin along with drugs designed to fight the virus. For many, it’s worth trying, as the supplement is generally considered safe (although anyone on medication should check with their healthcare provider before taking anything as it may interfere). Regardless, making sleep a priority is important. Keep a consistent bedtime –– even if it’s after midnight. Avoid the blue light from computer and smartphone screens an hour or so before slumber. Abstaining from caffeine and alcohol in the evening can also help you sleep better. The most important thing is to remember that good sleep is as vital for your body as a healthy diet and exercise.

References

• The Benefits of Slumber
• The Extraordinary Importance of Sleep
• Singapore is the third most sleep deprived after Japan and India, Fitbit’s data indicates
• Obesity, Race/Ethnicity, and COVID-19
• Studies find that people are sleeping more during COVID-19 pandemic
• COVID and Sleep: Better Slumber During the Pandemic May Help Protect Your Health
• Facing up to long COVID
• Melatonin potentials against viral infections including COVID-19: Current evidence and new findings