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(Latin ‘circa diem’ or ‘approximately a day.’) 

Circadian Rhythms

It’s extremely important for every one of us to ‘get this right’ but as we travel further into the 21st century our lifestyles are growing further and further apart from our fundamental needs.

There’s a clock that ticks away inside our cells. Plants and animals have one too.

This clock allows us to synchronise our activities with the day-night-day-night cycle that results from the Earth’s rotation. 

It prompts our body to sleep and wake at the right times. 

Trouble is that these days we live in a 24 hour society, disconnected from the natural rhythms of Nature. 

  • It never truly gets dark. Light pollution stops us from seeing the stars. 
  • Light pollution from outdoors or even from LED displays in our bedroom can stop us from sleeping properly.
  • The opportunity for rest and renewal afforded in darker months does not occur in lighter months, yet we are expected to be as productive in Summer as in Winter.
  • We take exercise in gyms rather than in open air and switch off the TV with a remote when we are well past the point of tiredness. 
  • We adopt timetables for when we eat, how long we work, when we go to bed; we attend late social engagements, ingest too much sugar, prescription drugs and drive to shopping malls, some believe“….to fill those empty holes in our lives.”
  • The technology of mobile phones, laptops and the internet stops us getting away from work, especially when we should be utterly independent of the office on holiday.
  • Our children sleep with their iphones beside their pillow anticipating the ping of incoming text messages to arrive through the night.  

Circadian Rhythms is a fascinating topic that has captured the attention of scientists and researchers for centuries.

And as someone who has spent countless nights burning the midnight oil, I can tell you firsthand how important it is to understand the workings of this intricate system.

But what exactly are Circadian Rhythms?  Put simply, they are the natural, 24-hour cycles that govern everything from our physical, mental, behavioural changes and sleeping patterns to our hormone levels, metabolism and even our cognitive function. 

They are controlled by a group of specialised cells in the hypothalamus called the suprachiasmatic nucleus, which receives signals from light-sensitive cells in the eye and adjusts the body’s internal clock accordingly.

And while most of us are familiar with the basic concept of Circadian Rhythms – we know that we’re supposed to sleep at night and be awake during the day – the truth is that these cycles are more complex than we ever imagined. 

There are multiple circadian rhythms in the body, each with its own unique pattern and function.

Sleep: A Vital Medicine

One of the best known is the sleep-wake cycle that is regulated by the hormone melatonin. This hormone is produced by the pineal gland in response to darkness, and it helps to signal to the body that it’s time to sleep. 

But melatonin isn’t the only hormone involved. There’s also cortisol, a hormone that is released in response to stress and helps to keep us alert and focused during the day.

And it’s not just hormones that are involved in Circadian Rhythms – our genes play a role too. 

Recent research has shown that there are certain genetic mutations that can disrupt the body’s internal clock, leading to sleep disorders, mood disturbances and even an increased risk of certain diseases.

So what does all of this mean for us? Well, for one thing, it underscores the importance of getting enough sleep and maintaining a regular sleep schedule. 

Perhaps most importantly, understanding Circadian Rhythms can help us to appreciate the incredible complexity of the human body. 

We may never fully understand all of the intricacies of our internal clock, but by studying it and learning from it, we can gain a deeper appreciation for the amazing anatomy we function in.

For Shift Workers

Because shift workers operate outside the 24-hour cycles of light and dark, theri body’s natural Circadian Rhythm can be thrown out of kilter, leading, long term, to a range of health issues, including:

  1. Sleep disturbances, making it difficult to get enough sleep, which can cause fatigue, decreased alertness and reduced cognitive function.
  2. Increased risk of chronic diseases such as cardiovascular disease, diabetes and certain types of cancer.
  3. Mood changes and an increased risk of depression, anxiety and other mental health issues.
  4. Gastrointestinal disorders, disrupting the body’s natural digestive processes, leading to conditions such as constipation, diarrhoea and indigestion.
  5. Reduced fertility in men and women, likely due to disruptions in hormone production and other physiological processes.

The Downside

Disrupting the rhythms through irregular sleep patterns, excessive screen time or continuous late-night activities can lead to consequences such as reduced productivity, impaired cognition, weakened immune system, mood swings and increased risk of chronic illnesses.

I was interested to note that the Nobel prize committee described these findings as having “vast implications for our health and wellbeing”.  

Whilst I applaud the committee for recognising and rewarding such empowering research, Circadian Rhythms were first brought to our attention by Androsthenes in the 4th Century BC when he observed the diurnal movements of a tamarind tree leaf.  

13th century Chinese medical narrative also observes this diurnal process as do an increasing number of scientists in subsequent centuries.  

It was not however until the 1950’s that German scientist and Founder of Chronobiology Franz Halburg coined the word ‘Circadian’.

If you’re getting up to start every day on purpose……great.  But if you’re getting up to go to school or to a job that doesn’t push all the right buttons, scientists have revealed their findings that school/work should NOT start before 10am.

(Click Here) Minds: Starting work before 10am isn’t just soul crushing, this scientist says it’s equivalent to torture.

Somehow I don’t think your teacher or boss will go along with this.

Graeme Dinnen

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