Why Do We Need to Sleep?

Everyone knows how much better you feel after a good night of sleep, but the science behind why we need it is only now coming to light. It turns out that sleeping isn’t just about resting and taking a break; it affects every system in your body on a cellular level. Sleep repairs your body, helps fight disease and strengthens key systems that help you look and feel healthier. It also improves your ability to learn and concentrate, and may even keep you from gaining weight. Yet, many people don’t get enough sleep to stay healthy. In fact, a lack of sleep can actually lead to health problems including high blood pressure, diabetes and depression, and increase the risk of accidents that could cause serious injury or death.

Researchers aren’t sure exactly why we need to sleep, but several theories have been proposed. One is that sleeping evolved as a way to conserve energy and reduce the risk of predators after dark. Another is that it allows your brain to reorganize itself, and strengthens memories by turning short-term ones into long-term ones. Finally, it may clear out waste from the central nervous system by removing excess proteins that build up during the day and can contribute to dementia.

All of these processes are active during the sleep cycle, which lasts about 90 minutes to two hours. During the first half of the sleep cycle, your eyes move rapidly in front of you, and brain waves are similar to those during wakefulness. Then, your brain switches to REM sleep, and the eye movements stop. At the same time, your heart rate and breathing increase, and you may dream. During the last stage of sleep, called SWS (Slow Wave Sleep), you enter deep SWS and your brain’s glymphatic (waste clearance) system removes excess proteins from the brain.

While you’re sleeping, your body releases growth hormone and the immune system gets a chance to repair cells damaged by stress, exercise or illness. It’s important for regulating your mood, supporting good judgment and decision making, and keeping you energized throughout the day. Sleep also helps regulate your body’s glucose and cholesterol levels, as well as support your metabolic rate and help you maintain a healthy weight.

The more you sleep, the more energy you’ll have for the rest of your life. And a good night’s sleep will make you more resistant to illness and infection, especially common colds. For most adults, it is recommended to get about 7-8 hours of sleep each night. But if you are having trouble getting to sleep or staying asleep, talk to your doctor. They can help you determine what is causing your problems and provide tips on improving your quality of sleep. If you have severe problems with your sleep, it may be necessary to see a sleep specialist, who can evaluate you for sleep disorders and treat them. They can also refer you to other specialists if they think that you need it.