Reading time – 10 minutes
Category – science
A modern human being is obsessed about profits and bank balances and hence, easily forgets about real wealth, that a man can desire and achieve.
A healthy body with a healthy mind is the most precious thing one can achieve.
Everyday, every human on the face of the earth does a thing which is most undervalued and neglected; inspite of being a absolute healer.
Sleep is an automatic and useless thing till we are unable to sleep even after trying or time doesn’t permit for it.
In this article let’s see what is the latest scientific knowledge about sleep and how it can help us .
Every living being on earth has a circadian rythm, which is internal clock set by the Sun over the millennia.
It was shown in plants in 1729. And after two hundred years it was shown in humans too.
It decides our waking and sleeping times. It is controlled by suprachiasmatic nucleus situated just above the point where both optic nerves cross each other.
It controls various rythms in body like temperature, metabolic rate, sugar levels, adrenal hormones and other vital functions.
Circadian rhythm varies in different people. Around 40% are morning type, who go to bed early and get up early in the morning.
30% are night types who sleep late and hence get up late. It includes the author of this article.
30% fall somewhere in between.
There are two main things that control sleeping habits of humans.
1. Circadian rhythm controlled by suprachiasmatic nucleus. It signals release of Melantonin which is a hormone secreted by pineal gland. It signals as a starting signal to the person that dark has arrived and you should try to sleep. It is a signal but it doesn’t help in induction of the process of sleep.
2. Sleep pressure – During wakefulness adenosine accumulates in the brain neurons which creates a pressure on the person to sleep. When we sleep it is cleared and sleep pressure falls to normal
Most important thing is that these two systems work independent of each other.
Types of sleep.
Let’s now come to sleep. It is mainly of two types depending on whether your eyes move automatically in your orbits or not at a particular point while you are sleeping..
1. NREM is non REM sleep in which eyeballs show only slow rythmic movements.
2. REM – Rapid eye movement sleep – in it eyes dart fast in the orbits.
Individual pecularities of both types of sleep.
NREM has 4 stages going from light ( stage 1) to stage 4 ( very deep).
It is believed to be a phase of consolidation of new information and facts. It declutters unwanted and less useful information from the neural connections.
It dominates first half of the night.
It is main sleep after a long period of sleep deprivation.
EEG in it is slow wave.
During this dreaming occurs. Muscles loose tone. Eyes dart fast. It is believed to be responsible for integration of new data with other data and old information available in brain’s neural connections.
It is hence place for creativity and innovation as it connects different fields of information which are unrelated.
It is important for brain development of infants and kids. Hence REM sleep is more in early age and reduces as we age.
Quality and quantity of sleep reduces as we age.
Factors affecting sleep.
1. Caffeine – It competes with adenosine binding sites in brain and reduces sleep pressure. It’s half life is 6-7 hours. So avoid consuming caffeine during second half of the day.
2. Alcohol – Fragments sleep and disrupts REM sleep. Restorative power of sleep falls.
3. Temperature – Fall in the core temperature of the body helps in inducing sleep. Shower helps. Cool room helps. Excercise just before sleeping disrupts this effect.
4 Jet lag – Confuses circadian rhythm.
Areas of sleep generation.
Mid frontal cortex just above nasal bridge is site of the origin of sleep. And it spreads backwards towards occipital lobe. These are the areas which are earliest to degenerate as we age.
What happens if we sleep less.
Decreased memory, retention and reproduction of the facts. Increased chances of diabetes, infections and cancers. Increased emotional liability and obesity. Increase incidence of psychiatric illness.
Increased incidence of accidents.
Do sleeping pills help.
No . They produce unnatural sleep. They have addictive potential. Rebound insomnia can occur. People taking pills have increased mortality over next two and half years.
Normal length of sleep
Generally eight hours of good quality of sleep is recommended. It follows J curve like water consumption and food intake. After 9 hours, benefits of sleep start to reduce again.
New enemy of sleep
Blue LED light reduces Melantonin secretion by 50%. It also reduces REM sleep. Hence reading a paperback is better than reading on an ipad near the bedtime.
At last what helps us to sleep
1. Stay away from caffeine, alcohol and nicotine.
2. Stick to a sleep schedule. Try to go to bed at same time and get up at same time.
3. Excercise but not close to the time of sleeping.
4. Avoid day naps after 3 pm.
5. Avoid medicines that disrupt sleep.
6. Avoid large meals near bedtime.
7. Wind down before sleeping. Do something that relaxes you.
8. Dark room. Cold room. Gadget free room. Keep the clock away. Comfortable bedding.
9. Taking Bath before sleep can help lower your body temperature.
10. Get cozy with sunlight. Get one hour sunlight exposure in morning and dark indoors in the evening.
11. Don’t stay in bed if you are not sleeping. Do some relaxing stuff like reading a paperback. And return to the bed when you feel sleepy.
Inspiration – Why we sleep by Matthew walker.
Get your copy.