Americans are more sleep-deprived than ever. Yet, this wasn’t always the case. In 1910, people slept for about nine hours a night. Today, that number has dropped drastically to less than seven hours, likely fuelled by technology and the internet, which gives us more excuses to stay awake. If there’s one thing we’ve heard often enough, it’s that we need to get 7 to 9 hours of good sleep each night. Too little sleep leaves us bleary-eyed and foggy-brained, while too much sleep makes us groggy. But why is this? Why can’t we sleep for less than 7 hours or more than 9 hours without feeling refreshed? Does it pose any real danger to health, or is it just a myth? In this article, we take a look at the science between this sweet sleep spot.
Before getting into the details of why we need 7-9 hours of sleep, you need to understand what happens during sleep and how sleep itself works. Each night, you go through several stages of sleep: stage one, stage two, stage three, stage four, and Rapid Eye Movement (REM) sleep. The first stage is a light sleep stage where your brain produces alpha and theta waves, and you’re easily woken by disruption. In stage two, sleep becomes a little heavier. Brainwaves spike and then dip. From here on out, your brain produces slow delta waves, and you enter stage three and four of sleep. You won’t awaken easily. Your body undergoes restoration as muscles and tissue repair. Your brain rids itself of waste via the cerebrospinal fluid. Once the fourth sleep stage is complete, you move back to stages two and three before entering REM sleep where your brain becomes active. You begin dreaming, and eye movement increases. In this stage, your brain consolidates new information that you’ve learned the previous day in order to form memories.
Most of us go through five sleep cycles each night. One cycle takes approximately 90 minutes to complete, which is around 7 to 9 hours. Being able to complete each sleep stage and cycle through them five times is important in order to feel rested the next day. If you sleep too little, you won’t be able to go through all the stages. Waking up in the middle of a sleep cycle can also prevent you from feeling rejuvenated. Conversely, too much sleep can also leave you tired and not at your best. While the science behind this is more unclear, it’s believed that sleeping too much is a sign of disrupted sleep. For instance, if you have sleep disorders like restless leg syndrome or sleep apnea, you can’t sleep peacefully through the night. Those frequent awakenings compel you to sleep more to compensate. What’s more, having disrupted sleep puts you at risk of developing health conditions in the long run. Those same health conditions may, in turn, make it difficult to sleep well, creating a cycle.
Poor sleep and oversleeping can create numerous health problems, including heart disease, stroke, diabetes, and high blood pressure. It even kills sex drive and can contribute to unhappy relationships, at work, and at home.
Now that we know why we need 7-9 hours of sleep, the only thing left is to get it! But that’s easier said than done. If you have trouble hitting the 7-9-hour mark, try making changes to your lifestyle and sleep routine. You should avoid consuming caffeine and nicotine, especially before bedtime. Since they’re stimulants, they’ll prevent you from falling asleep easily. In a study by Freiburg University Medical Center, nicotine users were found to have a shorter sleep period time, longer sleep latency, more sleep apneas, and leg movements in sleep than non-smokers. In addition, you should follow a set bedtime routine as this trains your body to settle into a regular sleep-wake schedule.
Along with these, consider changing your mattress to one that promotes sleep and comfort like the Nuvanna mattress. Designed by a material scientist with over 20 years of experience, it features three layers that address excess heat, motion transference, and poor support – factors that all disrupt sleep. The cooling top layer uses phase-changing gel particles to absorb heat and disperse it away from the body. The middle layer isolates motion and prevents it from being transferred across the surface of the bed. The bottom layer supports the entire length of the body and keeps the spine aligned. Together, the layers encourage uninterrupted sleep the whole night through.
Making lifestyle changes takes time and effort, but it’s worth it. You’ll sleep better and enjoy the many benefits that come with sleeping well, such as a healthy weight, a sharper mind, and more energy. You’ll also keep dangerous health conditions at bay. So starting today, make sleeping 7-9 hours your goal!