The feeling of waking up well-rested after a good night’s sleep is one of the simplest pleasures in life. But it’s much more than that: during slumber, your body is hard at work, fixing muscles, cleaning up cell debris, restoring hormone levels and forming memories. In fact, there are few health factors as consistently linked to your well-being as getting enough sleep.
Insufficient or poor-quality sleep can lead to a variety of physical and psychological problems, including obesity, heart disease, depression, diabetes and more. Even if you are not suffering from any of these conditions, lack of sleep can affect your energy level, concentration and mood. Sleep is so important that it’s considered to be one of the human body’s “primary functions,” along with digestion and metabolism.
Scientists have been studying sleep for more than 100 years. But there are still many questions about its function and how it works. For example, researchers are still not sure why humans need sleep. One theory is that sleep helps conserve energy. Another is that the brain needs to reorganize itself and clear out waste products. Another theory is that sleep allows the immune system to work properly and fight off infection.
Other research shows that during a phase of sleep called non-rapid eye movement, blood flow increases to the muscles and tissues, which allows them to repair themselves. This is thought to help your body heal after a strenuous workout or injury. It also may help reduce chronic pain, such as from arthritis or injuries to the back and spine. In addition, sleep may improve cognitive functioning by helping you concentrate and make fewer mistakes. Researchers are exploring the role of sleep in emotional regulation as well.
During the first non-rapid eye movement stage of sleep, or deep sleep, your eyes don’t move, and your brain waves slow down. Then comes REM sleep, or rapid eye movement. During this phase, your heart rate and breathing increase, and you dream. REM is thought to be critical for learning and memory.
Sleep is also important for maintaining a healthy weight and controlling your blood sugar, cholesterol and blood pressure levels. Studies have shown that getting adequate sleep can help you avoid heart attacks, stroke and high blood pressure, and it may lower your risk of diabetes by improving how your body uses insulin. It can also boost your immune system and help you stay stronger, which may protect you from diseases like the common cold or the flu. And it can help you recover more quickly from illness or surgery. Interestingly, researchers have found that people who get adequate sleep are more likely to practice other healthy behaviors, such as exercising regularly and eating a balanced diet. That’s why experts recommend that you make sleeping a priority in your daily life. Stick to a regular schedule and do things to help you relax before bed, such as having a warm bath or reading a book.