Sleep Apnoea Articles

Regular circadian rhythms can help sleep disorders

Here’s something you may have heard before:

“Go to bed and wake up at the same time, even on weekends. Our bodies are creatures of habit; they love a good routine.”

But maybe this is not so familiar:

“Our cells and internal organs each have their own internal biological clock.”

From ‘Circadian Rhythm’ to circadian rhythms

For a long time, scientists (and the rest of us) thought of the brain as a master command centre. It would send out signals to the body saying “okay lungs: inhale, then exhale.” Or “okay body, you’ve been awake for 16 hours, it’s time to sleep.” And from a big-picture level, that made sense.

In recent years however, scientists have posed fundamental challenges to the command-centre theory by asking questions like these:

  • How come your whole body – not just your sleep schedule – feels “off” if you change time zones?
  • How come eating later during the day tends to produce more weight gain than eating the same meal earlier

Not one clock, but many

It turns out that our bodies – and the cells that make up our organs and tissues – operate not under a single master clock, but rather by a series of clocks that synchronise as part of our overall circadian rhythm.

In trials with mice1, scientists have found that when they shifted sleeping and eating schedules in mice, the mice not only gained more weight but their new behaviour also altered the mice’s functioning on a cellular level.

This research into the influence of circadian rhythms may have profound consequences for understanding human health. When we veer off schedule – in activities like sleeping, and eating – we disrupt our circadian rhythms and may cause dysfunction2 at the cellular level. Scientists may be cracking the biological code for that age-old human sense of the importance of routine to daily life.

Sleep is a ‘force multiplier’

What does this have to do with you? It suggests there may be serious consequences for having an inconsistent sleep-wake schedule:

  • You could be packing on more pounds3 than you realise if you eat later in the day rather than earlier.
  • You could also be more vulnerable to metabolic diseases4 such as high blood pressure, diabetes, and high cholesterol.
  • You could be making more mistakes if you’re forgoing sleep to finish a project for work or school the night before it’s due, or if you’re giving a presentation right after that red-eye flight.
  • If you’re exercising, you’ll have to work extra hard just to get the minimum results.

Given everything that we do have to juggle day in and day out, choosing to make our lives even harder seems pretty dumb. Who really wants more work?

Keeping clocks running well

One important way to help keep your internal clocks running in sync and on schedule simply go to bed and get up at the same time. Really. By establishing and maintaining a consistent sleep schedule, you’re allowing for greater synchronisation within your body of all these different clocks. You’ll be smarter, fitter, and more alert as a result.

Get with a routine

If you don’t have a sleep-wake schedule in place – or if you’ve fallen away from your routine – there’s no time like now to start.

Spend the next week implementing a schedule that allows you to go to bed and to wake at the same time every day. That’s weekdays and weekends, both. It may take a little effort, but commit to 7 consecutive days of the same bedtime and rise time. You’ll find your schedule will get easier to follow once you’re used to it, and you’ll be doing important good for your health and well-being, now and over the long term.


Obesity and Metabolic Syndrome in Circadian Clock Mutant Mice, 21 April 2015

Biological role and clinical relevance of central and peripheral circadian clocks, 26 February 2013

Circadian timing of food intake contributes to weight gain, 3 Sept. 2009

Circadian disruption and metabolic disease: findings from animal models, 3 August 2010


Read Dr.Guy Meadows’ tops for a better night time routine

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