Sleep : a vital function

Sleep: a vital function for our organism
We spend one third of our life sleeping, so let’s care about it! Yet, today, sleep deprivation has become a fact: we sleep on average 1.30 less than 50 years ago ….⁽¹⁾

How can we learn to sleep properly again? How can we find this refreshing sleep again?By understanding what sleep really means through 5 different key points

5 key points about sleep

What is sleep?

Sleeping is a vital function of the body, like breathing, digesting or immunity. We spend one third of our life sleeping. During sleep our body works slowly as far as our brain activity; heart; lungs, muscles are concerned : our pulse slows down, our blood pressure drops; our breathing decreases ; our muscles lose their tonicity ; our body temperature diminishes too ⁽¹⁾

What are the sleep cycles?

Sleep is not continuous; It consists of different stages progressing into identical cycles throughout the night. These stages are divided into:

•Slow sleep: may be light sleep (Stage 1 ), intermediary sleep ( stage 2) or deep sleep ( stage 3), • Paradoxical sleep: also called rapid eye movements sleep or REM sleep. The dreams we make are best remembered during this cycle.

Sleep is composed of different successive stages. A sleep cycle lasts around 90 minutes for young adults; every cycle starts with light sleep and ends up with Rem sleep. Deep sleep mainly occurs during the first part of the night while light and REM Sleep are more numerous during the second half of it. A night’s sleep can be represented by an hypnogram as below:

Why do we sleep?

Sleep is essential for numerous reasons : • the learning and retaining of new knowledge, • muscle, skin and bone repair, • Growth in children and in young adults, • The recovery of the energy stores of the body…

^{The researches carried out on sleep are still being newly developed and scientists are still unsure of all the different functions of sleep.(1,2)}

How many hours of sleep do we need?

We all have our own sleeping patterns, with our own sleeping schedules and habits: whether we are a heavy or light sleeper; an early or late riser… our belonging to a specific group of sleepers as well as the particularities of our sleep ( the amount of necessary sleeping time, the length of the cycles, etc.…) are genetically determined. The ideal sleep time duration is the one which gives you the feeling of being fit and efficient the next morning: on average the 25-45 age group says it needs around 7.30 hours of sleep to be fit the following day.

Today sleep deprivation is a genuine public health issue: on average, we sleep 1.30 hours less than 50 years ago

45% of the French believe they sleep less than what they need ⁽³⁾

What are the consequences of a lack of sleep on the body?

As long as the lack of sleep is moderate and punctual, its consequences are limited. However, even a limited lack of sleep can have serious consequences if it occurs regularly : weight gain, headache ; less motivation, learning difficulties, school dropout, professional concerns , not to mention drowsiness, the first cause of car accidents.

In the long run, a lack of sleep increases the risk of numerous diseases: diabetes, cardiovascular diseases, blood hypertension, gastrointestinal disorders, viral infection and depression

45% of the French believe they sleep less than what they need (3)

45% of the French believe they sleep less than what they need ⁽³⁾