Sleep Deprivation - Less than 7 hours rest?
Sleep deprivation, what is the meaning of this? If you’re not getting enough sleep this can create a ripple-like effect on the rest of your life – your performance, mood, cognitive functions, coordination, weight, libido and a general deterioration of health with a lack of efficient recovery being the contribution. Some can find that this occurs just by struggling to get a good night’s sleep, but one other factor that can contribute to sleep deprivation is nightshift work, long hours with limited rest and burning the candle at both ends. The irony of health is that many health professionals struggle with this with such long hours! Especially those involved in an emergency, there is no sticking to a specific clock off time, you often don’t have a choice!
Why is sleep so important then? How can it have such a massive flow-on effect on so many parts of our lives! It doesn’t seem fair really… 20% of the adult population fits the profile for sleep deprivation, that’s a large portion… what if you do have that 7-8 hour window of sleep it doesn’t mean that it is quality sleep.
Why do humans sleep?
Well, nearly all animals sleep and this state is considered in science to be a reduced state of responsiveness, motor activity and overall metabolism in the body. A limited state of consciousness but not total unresponsive unconsciousness like that of coma or anesthesia.
Let’s start with the phases of sleep:
There are two phases of sleep – Rapid Eye Movement (REM) and Non-Rapid Eye Movement (NREM). Within this, an average sleep phase will contain within it 5 cycles throughout.
Non-REM has 3 subcategories:
Non-Rem 1 – the initial transition from wakefulness to sleep, limited eye movement occurring. This is a very subtle and light sleep stage, so light that being awoken will feel as if you were not even sleeping.
Non-Rem 2 – 50% of your total sleep cycle happens in this stage. This is a deep but not the deepest sleep state, it’s the transition to the deepest.
Non-Rem 3 – 10-20% of your sleep happens here – the deepest sleep state. This is the most difficult stage of sleep to be awoken from.
REM Sleep: Around 20% of sleep occurs in this phase, with very rapid eye movements happening and simulation of paradoxical wakefulness. This is where dreams occur, visons created in the subconscious. Its a realm that science is still discovering as its so purely fascinating.
These two sleep phases alternate in between each other over a full 7-8 hours sleep.
Physiological benefits of sleep? Where do we go when we fall asleep?
Well let’s have a look at what happens to the body during:
- Slowing of Brain Activity.
- Heart Rate slows.
- Blood pressure lowers.
- Respiration and breathing rhythm slow.
- Airway resistance decreases.
- Body temperature is lowered.
- Sexual arousal in infrequent moments.
- Sensory and motor activity increased in comparison with NON-Rem.
- Heart rate increases from Non-Rem.
- Blood pressure increases around 30% from the state of Non-Rem.
- Blood flow to the brain increases anywhere from 50-200% from Non-REM.
- Respiration increases In comparison with Non-rem, APNEA usually occurs in REM sleep states.
Sexual arousal more frequent from Non-Rem in both men and women (Dream state) may have a role here.
So, we know that these changes occur in sleep, but these are usual functions – why is it so critical for sleep? Well, we still don’t 100% know why we do it. There are however theories…
“Energy conservation theory: From an evolutionary perspective, if the food was scarce, then this state of lowered caloric needs would promote survival.
Restorative theory: This theory implies that the body rejuvenates and repairs during sleep. Sleep reverses the damage that occurs in waking, including oxidative stress, depletion of energy stores, death of neurons in the hippocampus, and downregulation of receptors.
Information processing theory: This theory argues that sleep promotes learning and storage of memories by returning saturated learning circuits back to baseline levels.” - (From Biological Sciences Curriculum Study. Sleep, sleep disorders, and biological rhythms. Bethesda (MD): National Institutes of Health; 2003. NIH publication no. 04-4989.)
The biggest issue with sleep deprivation is that over time it becomes that of an accumulative debt. It takes a lot to restore balance. Long term disruption of our natural circadian rhythm. Our day/night cycles can have impacts short term and long term.
The short term being exposure to sleep deprivation:
- Increased weight gain.
- Cognitive issues, brain fog, poor attention span, mood disorders.
- Increased release of Grehlin and limited amounts of leptin. Meaning that cravings and hunger are constant. Usually, palette satisfying salty and sugary foods.
- Increased likelihood of depressive and anxious states.
- Increased risk of diabetes due to insulin resistance.
Long Term exposure to sleep deprivation:
- Increased risk of cardiovascular disease.
- Higher increased the likelihood of developing Alzheimer’s.
- The higher increase in developing osteoporosis.
- 4 x increase of early life mortality.
Modern-day sleep impairments we never had exposure to before now:
- Blue lights from electronic devices interrupting melatonin disrupt REM sleep stages reduce alertness in the morning due to interruptions of delayed sleep, cortisol, and melatonin.
- Gut health and poor nutrition.
- High amounts of stimulants consumed.
- Higher exposure to stress and anxiety triggers disrupting cortisol patterns.
- Low-grade inflammation from viral exposure or past unhealed structural injury.
What can you do to combat it?
- Switch off devices at least an hour before bed.
- Get your cortisol screened.
- Eliminate stressors where possible, at least the avoidable ones.
- Use cortisol and anti-inflammatory compounds to balance your stressors, these are usually adaptogens such as Ashwagandha, Schisandra berry, Turmeric/curcumin, Rhodiola. \
- Improve your diet – poor diets are massive contributors to poor sleep, recovery, and anxiety/depressive states.
Cherish your sleep, it takes up 1/3 of your life… you might as well live a full happy and healthy life!
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- Sleep Deprivation Robert M. Abrams, MD