Scientists estimate the human brain houses as many brain cells (neurons) as there are stars in the Milky Way, about 100 billion. Those brain cells “talk” to each other, sending messages across about 100 trillion lines of communication, called neural connections. In short, the human brain is the most complex thing we know of in the universe. And it needs its sleep.

Specifically, one-third of our lives should be spent sleeping. Not getting enough shuteye affects everything from our immune system to our memory and mood. In the time of COVID-19, sleep is especially critical.

In Oregon, insufficient sleep (fewer than seven hours daily) has been linked to many chronic conditions including depression, heart attack, cancer, stroke, asthma and obesity. It has even been linked to having suicidal thoughts among people who may not be clinically depressed.

What exactly is the brain doing while we sleep that’s so important?

• Recharging: Just like a cell phone may need recharging overnight, so do our brains. A good night’s sleep means we start each day with a fully charged battery that typically runs out by bedtime.
• Housekeeping and waste management: Our brain has a tool that filters out waste when we sleep, preventing harmful toxins from building up in the brain. Also, those 100 trillion neural connections get stronger. You can think of sleep like a software update for your brain.
• Rapid-Eye Movement (REM): This phase of sleep is when most of our dreams occur. It’s thought to be a time when we process emotions and recover from stressful events. The late morning hours shortly before you wake up tend to be REM heavy, so if you’re cutting sleep short (e.g. with an alarm clock) you may be losing out on much-needed REM sleep for your mental health. Kim Hutchison, M.D., FAASM is associate professor of neurology and sleep medicine at Oregon Health & Science University, says “When you specifically deprive somebody of REM sleep after a traumatic event, they tend to have more PTSD.”
• Non-Rapid Eye Movement (NREM): There are a few stages of NREM sleep, and the deepest stage is when your body’s energy gets restored. In addition, NREM sleep is when short-term memories turn into long-term memories, which helps keep us sharp as we age and strengthens our ability to learn and be creative.

Sleep, COVID-19 and immunity

When we don’t get enough sleep, our immune systems can get weaker due to reduced antibody production. This makes us potentially more susceptible to infections including COVID-19.

When sleep problems start or get worse because of the pandemic due to illness, general stress or distress, scientist have now dubbed this “COVID-Somnia,” which can result in a vicious cycle of mental and physical health problems and disrupted sleep.

Stress and anxiety caused by the pandemic may make it hard for your thoughts to quiet down when you go to bed, and your mind races. In other words, you can’t stop thinking about things. That makes it harder to fall asleep and, once you do, more likely you’ll wake up periodically. According to Hutchison, this pattern can be self-perpetuating. “If you have a few nights in a row where you wake up and can’t go back to sleep, you’re more likely on future nights to not be able to go back to sleep because then you’re also worried about not falling asleep.” Hutchison describes this as a “panic button” in your brain that struggles to turn off.

No time for sleep

For some people it may be difficult to get adequate sleep due to factors out of their control, such as working multiple jobs or taking care of very young children. If you have trouble finding the time to sleep, try to prioritize catching up on sleep when you can. Ask for help from family members or friends, or take naps if possible. This may not solve the problem, but it can help manage it.

We may not know everything about the most complex thing in the known universe–our brains–but we do know that sleep is critical to our mental health and immune systems. The Centers for Disease Control and Prevention recommends we get at least seven hours of sleep per night. Many need a bit more. Check out the graphic on this page for tips on how to fall asleep faster and get better quality sleep.

If you are getting fewer than seven hours of sleep and routinely have trouble falling asleep, or if your sleep is frequently disturbed throughout the night, contact your health care provider. If you don’t have a health care provider, call 211.