Insomnia, Sleep Cycles & How They Impact your Health

Insomnia is a sleep disorder that causes an inability to sleep sufficiently.  It impacts both sleep quantity and quality.

Symptoms of insomnia include:  

1) Trouble falling asleep or staying asleep. This can lead to tossing and turning throughout the night or waking up frequently during the night.

2) Worrying about falling asleep while trying to sleep, or tossing and turning at night, unable to fall asleep.

A diagnosis of insomnia requires that these sleep problems occur at least three nights per week, over at least a 3 month period.

Research says that people who sleep between 6.5 and 7.5 hours live longer than those who sleep more than 8 hours per night.  People that sleep 9 to 10 hours a night do not live as long as those who sleep as little as 5 or 6 hours a night.  People who sleep between 7 to 10 hours have the highest well-being scores.  Though longer sleep could be a symptom of and underlying health condition than rather a cause for a shorter lifespan.

We do not need more hours of sleep to make up for lost sleep.  Our body naturally takes care of this problem by spending a greater portion of time in deep sleep on the following night.

Stages of Sleep:

N1:  This is between being awake and falling asleep.  It is a light sleep and easily interrupted lasting about 1 to 7 minutes.

N2: The onset of sleep is still light but you become unaware of surroundings.  Breathing and heart rate slow down, become regular, brain wave activity slows, and body temperature drops.  This cycle lasts about 10 to 25 minutes per sleep cycle and makes up 50% of total sleep.

N3: This is the deepest and most restorative sleep.  Your blood pressure drops, breathing becomes slower, muscles relax, blood supply to muscles increases, tissue grow and repair occurs, and energy is restored.  Hormones are released for muscle development.  This cycle last 20 to 40 minutes and happens mostly in the first half of the night. This is the most restorative stage.

REM (Rapid Eye Movement):  This cycle first occurs about 90 minutes after falling asleep and again every 90 minutes, and last longer later in the night. First cycle lasts 10 minutes increasing to 60 minutes in later cycles. Dreaming occurs in this cycle.  Your brain is active during this cycle, providing energy to the brain and body, and supporting daytime performance.  Blood pressure, heart rate, and breathing increase.  Eyes dart back and forth.  Your body becomes immobile and relaxed, as muscles are turned off.

Full Sleep Cycle Breakdown:

A full cycle lasts about 90 to 110 minutes.

The first half of the night has more deep sleep (N3).

The second half has more REM sleep, with longer REM periods closer to the morning.

Optimal sleep means completing multiple cycles (4 to 6 cycles per night), ensuring deep and REM sleep for full recovery.

How getting less than 4 sleep cycles will impact you:

Less deep sleep (N3): Poor physical recovery, reduced muscle/tissue repair, weaker immune function, increased risk of injury and chronic pain.

Less REM sleep:  Poor memory consolidation, difficulty learning and problem solving, increased stress, anxiety, and mood swings.

Not getting enough sleep cycles increases fatigue and health risks.  You are at higher risk of heart disease, diabetes, and weight gain.  Also have elevated cortisol (stress hormone) levels, and increased risk of metabolic issues and inflammation.

Long term effects can put you at an increased risk of neurodegenerative disease like Alzheimer's and a higher risk of cardiac issues.