What Happens When We Sleep

The Importance of Sleep to Our Physical Health

Scientists and researchers are still learning why we sleep. What we do know is that our bodies secrete many important hormones while we sleep. These hormones control metabolism and many other bodily functions.


For example, cortisol, a stress hormone, enters our blood stream near the end of the sleep cycle to promote wakefulness. It’s the reason we wake up after a good night’s sleep.

Growth Hormone

The growth hormone helps regulate muscle mass and is also secreted mainly during sleep. Sleep actually helps your body get better results from your exercise routines. Hair follicle growth is stimulated during sleep.

Sleep Loss Consequences

Other hormones are secreted that influence appetite and weight. This is the reason we often wake up hungry. Therefore, sleep loss, or the lack of good quality sleep, contribute to diabetes and obesity as well as heart problems, depression and substance abuse, all of which have grown to epidemic proportions in recent years.

Neuron Repair

Sleep also gives neurons that are constantly used while we are awake a chance to shut down and repair themselves. Without adquate sleep, neurons become so depleted or polluted they begin to malfunction. Sleep likewise gives the brain a chance to exercise neurons that may deteriorate from a lack of acitivity.

Beauty Sleep

While we sleep many of our cells increase production of proteins, as well as decrease their breakdown. Protein is needed for cell and tissue growth and for repair from stress and ultraviolet rays. Deep sleep is actually “beauty sleep.”

Memory and Learning

Parts of the brain that control emotions, decision-making and social interaction are drastically reduced during sleep. This helps people maintain optimal emotional and social functions while awake. Studies also show that certain nerve-signalling that occurs during the day is repeated during sleep, helping to improve memory and learning.


We often automatically retreat to bed when we have a cold, flu, or sore throat. We seem to instinctively know that sleep helps us heal. This phenomenon is backed up by scientific fact – not just wishful thinking. The body’s immune system is severely delayed in people who are sleep deprived.

Pot Belly

Research shows that decreased slow wave sleep in young men is associated with decreased production of growth hormone. Growth hormone is vital to controlling the bodys proportion of fat and muscle, which when gone awry causes paunch or pot belly in later life.

Craving Carbs

Inadequate sleep also causes lower levels of the hormone leptin, which regulates carbohydrate metabolism. Low levels of leptin cause the body to crave carbohydrates – regardless of the amount of calories consumed. Lack of quality sleep makes us fat.

Mood Swings

Prolonged sleep loss is harmful to our nervous system, impairs memory, and causes hallucinations and mood swings.

This report is not a diagnosis. We hope this information can guide you toward improving your life.

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