The Benefits of Sleep

For a long time, scientists viewed sleep as an inactive state in which the body shuts down and takes a break. But a good night’s rest does more than just give your muscles a chance to repair themselves. During slumber, the brain organizes and stores information from the day. It also converts short-term memories into longer-term ones, which helps us learn. Sufficient sleep also boosts the immune system and clears toxins from the brain and body, keeping inflammation levels low.

In addition, the hormones that regulate hunger and stress levels are balanced during sleep. Studies show that those who don’t get enough sleep are at greater risk for obesity, heart disease and depression. Sleep deprivation can also affect mental health and make it more difficult to think, react and work effectively.

The body’s major restorative functions, such as tissue growth, muscle protein synthesis and cell repair, occur almost exclusively during sleep. The human body will normally spend four or five cycles of REM and N2 NREM sleep during a night, each taking about 90 minutes to two hours to complete. During REM sleep, the eyes move rapidly behind closed lids and brain activity is similar to that of wakefulness. This is when we dream. N2 NREM sleep is characterized by relatively deactivated brain waves and slow-speed eye movements.

Researchers are still debating how the different phases of sleep differ from one another, but there is a general agreement that the brain has multiple states of activation during sleep, including drowsiness and deep sleep. The drowsiness phase is characterized by slow-speed eye movements and a low level of brain activity, while the deepest stage of sleep is characterized by a very high level of brain activity.

There are several theories as to why the brain is so active during sleep. The most popular view is that the brain is preparing for the day ahead and transferring memories from short-term to long-term storage. Another theory is that the inactivity of sleep gives the brain a chance to rest and clear cellular and protein debris that can cause inflammation.

Scientists are also working out whether or not all mammals, birds and reptiles sleep, because there is evidence that some do. However, other research has found that the criteria used to identify a sleep-like state in these animals do not always match with those of humans.

It is important to understand that if you are suffering from a sleep disorder, you will not automatically get better by sleeping more. Getting adequate sleep can help reduce your symptoms, but you will need to treat the underlying causes of your problem to get the most benefit. Talk to your doctor if you are concerned about how much sleep you are getting, or if your symptoms persist for more than a few weeks. They can recommend the most appropriate treatment for you, depending on the underlying condition.