What happens in your body when you sleep?

3 Mins read

Sleep accounts for a quarter to a third of a human lifespan. That’s a fact. So what happens when you sleep? Long before, people and scientists believed that sleeping was a passive stage where brains go dormant or shut. But it turns out that the brain engages in some activities closely linked to the quality of life, said a sleep expert from John Hopkins. Researchers are working tirelessly to unearth the effects sleep has on the physical and mental health and what really happens during sleep. Here are some findings many of us won’t believe about sleep.

Sleep cycles

Not all sleep is the same. When you go to sleep, your brain starts to engage. Your brain will cycle through two states repeatedly until you wake up, namely: REM (Rapid Eye Movement) and non-REM. Your brain first enters into a non-REM cycle, which has four stages. The first stage comes between being awake and being asleep. The second stage is a light sleep mode. Here, your heart rate and breathing start to regulate, and the body temperature begins to drop. The last two stages are deep sleep. Long ago, the REM state of sleep was believed to be the most important sleep phase, but new data indicate that the non-REM phase is the most important phase for learning and memory restoration. It is believed that the non-REM phase offers more restoration overall compared to the REM state.

When your body begins to enter into the REM phase of sleep, eyes move rapidly behind the closed eyelids, the brain waves are believed to be similar to wakefulness. The breath rate increase while the body becomes temporarily paralyzed. The cycle repeats but now spending more time in the REM stage than on stage three and four of non-REM sleep. On a typical night, your brain will cycle through 4-5 times before you wake up.

Built-in sleep controls

Two main processes regulate sleep, namely circadian rhythms and sleep drive. A biological clock in the brain controls circadian rhythms, and one of the vital functions is to detect light cues. It is also connected to ramping up the production melatonin hormone at night and switching off when it senses light. People who are blind have trouble sleeping because they are unable to detect or respond to light cues.

Sleep drive, on the other hand, plays a key role. Imagine how you crave food when hungry; your body craves sleep too! There is a build-up of desire to sleep all through during the day, but your body demands sleep when it reaches some point. The only difference between craving for food and sleep is; your body won’t force you to eat, but your body will force you to fall asleep when you are dog-tired. Your body will even engage in some micro-sleep episodes about a second or two with your eyes wide open. And if you nap for more than 30 minutes during the day, it is believed to decrease your sleep drive.

Why you must sleep

If you have ever felt foggy during the day after a poor night’s sleep or a trans night, it won’t surprise you that sleep impacts your brain functionality. The first foot forward –sleep is vital for brain plasticity; in other words, the brain’s ability to adapt to new input. Researchers have linked little sleep to the inability to process what is learned during the day and, worst of all, the inability to remember what was learned. Sleep promotes the removal of waste products from brain cells, which happens while someone is asleep. Sleep is vital for the body’s health too. Without sleep, risks arise to depression, seizures, migraines, high blood pressure, and, worst of all, compromised immunity. Sleep is key to metabolism; a single night of missed sleep creates lots of metabolic imbalance in our bodies.

Now you know how vital sleep is to our bodies. It’s time to prioritize sleep for healthy living. A minimum of five hours of sleep per day is sufficient for an adult. Although there is still a need for research about sleep, experts work around trying to understanding how processes within the brain cells affect the ability to sleep.