Sleep is a behavior that occurs across the animal kingdom.
Even bacteria are known to have active and passive states that correspond to the sleep cycle of our body.
Major discoveries over the last couple of decades proved that sleep comes with a host of health benefits.
Sleep gives our body the opportunity to rest and recharge ourselves. In that time our body also focusses the energy in healing, detoxification, and repair processes.
Without this, our system will be subject to constant wear-and-tear with no opportunity to relax and repair itself appropriately.
What are the different stages of sleep?
The two main stages of sleep are:
- Non-Rapid Eye Movement (NREM)
- Rapid Eye Movement (REM)
NREM and REM occur in a recurring fashion every 90 minutes.
What is NREM?
The main aspect of NREM is that there is little or no eye-movement during this stage.
Other characteristic features of this stage include:
- Slow breathing
- Slow, regular heart-rate
- Low blood pressure
- Sleeper is relatively still
What are the stages of NREM?
The NREM has 4 stages:
Stage 1: A wake-to-sleep transition period where the person falling asleep can be easily woken up by softly calling their name.
Stage 2: A characteristic of this stage is specific bursts of electrical activity called sleep spindles. This help in the transfer of information from the short term to long term memory. A more intense stimulus can wake the person in this stage.
Stage 3: Progressing further, slow-wave activity marks stage 3, a period of deep sleep. The body begins its restorative process and sleep slowly transitions into stage 4
Stage 4: Called ‘the deepest stage’, the body’s reset process occurs now in full-swing: cells rebuild, protein synthesis occurs in high frequency, immune system is reset
Sleep then slowly ascends to the lighter stages of NREM (stages 1 and 2) and then to REM.
What is REM?
REM is the phase of sleep characterized by rapid eye movements.
Other characteristics of REM:
- Paralyzed body.
- The brain shows activities associates with wakefulness.
- Irregular heart rate
- Irregular breathing
- Prone to dreams
During REM, the information learned during the day is typically bounced around information boxes to relate this new piece to the existing ones.
This is often cited as a possible reason for dreaming.
Quick Fact: REM is a phase of sleep that is unique to birds and mammals.
About 90% of markers regulating sleep homeostasis is inherited
Several genes are involved in sleep regulation in humans.
Some of the candidate genes are CLOCK, PER2, PER3, DEC2, and GRIA3.
CLOCK gene is short for clock circadian regulator.
Quick Fact: One of the first genes identified to be associated with sleep is the CLOCK gene.
Variations in this gene cause behavioral sleep changes.
A to G variation- influences the way CLOCK activates other genes (ARNTL, PER2, PER3) in the circadian regulatory complex and delay the onset of sleep.
This determines the chronotype of an individual.
CLOCK gene variations have also been shown to influence the habitual duration - to be either a long sleeper (>8.5 hours) or a short sleeper (<7 hours).
Hand-picked content for you: The Expert Guide To Deep Sleep With Your DNA Raw Data
Tips for a healthy sleep
- Stick to a consistent sleep schedule:. Sleeping and waking up at the same time, even on weekends, can help us adjust to the pattern much faster and fall asleep as we are creatures of habit.
- Avoid cups of coffee late-afternoon to prevent caffeine circulating in the system when you go to bed.
- Avoid alcohol right before bedtime as it only helps in sedation.
- Do not exercise two or three hours before bedtime. This may increase your heart rate and make falling asleep harder.
- Have a hot shower before bed each night. This helps to drop core body temperature and help you fall asleep.
- Avoid using phones and tablets on the bed. Read a physical book instead.
- Journal for 5 minutes. This will help lift the stress of the day and keep you from tossing in the bed at night.
Of the 24 hours, humans have a recycling rate of 16 hours. That means, after every 16 hours, we need an indispensable 8 hours of shut-eye.
If you have been experiencing difficulty in sleep you could consider digging up the information in your genes and making the appropriate lifestyle changes that