Circadian Rhythms
The sun may rise is the East and set in the West – but is your body responding?
The circadian rhythms refer to our body’s internal clock, the innate connection to the whereabouts of the sun throughout the day – including when it is absent. This homeostatic mechanism is regulated by the light & dark, the temperature throughout the day, as well as ones eating patterns.
Dysfunctional circadian rhythms have shown to contribute to mental health issues, sleep disorders, cardiovascular issues, metabolic disorders, and poor immune function – as well as the disruption of many other important processes.
As the sun rises, our body registers light, this stimulates a rise in cortisol. Our cortisol levels – when regulated – peak around the same time each day. The reason for the cortisol peak is to rise you from rest, and wake your systems.
We get a natural cortisol decline throughout the day, and it begins to signal rest time as the day comes to an end. As the light fades, our body recognises dark. This is when our sleep hormone Melatonin is produced.
Melatonin is responsible for onset of sleep, but also plays a role in detoxification processes, neurological health, and healthy foetal development. Melatonin onset in delayed with the exposure to light in the evenings, and this partakes in the disruption of healthy circadian rhythms.
Understanding these levels is important, but it is also important to understand why so many of us are not in sync with our circadian clocks.
Firstly; light doesn’t stop for us when the sun sets. We live in a synthetically lit up space, and we glue our eyes to bright screens until we decide we need to sleep. Blue light is the main contender in this and has been linked to irregular circadian cycles, and delays the onset of Melatonin release.
We also aren’t prioritising sleep. Evidence has shown the direct link between those who don’t have a regular sleep schedule – such as shift workers & pilots; and the higher instance of metabolic issues and diabetes, as well as cardiovascular disease.
Ways you can keep your circadian rhythms regular:
Sleep 8 hours each night; ensure to try go to sleep and wake around the same time each day.
Turn off your devices at least an hour before bed, and if possible utilise ‘night mode’ on devices or use blue-light blocking glasses from the time the sun downs.
Regulate your eating patterns; aim to eat at the same time each day to create a balanced feeding cycle. Extended fasting times can trigger a stress response which spikes cortisol, especially in the evenings preventing the body from following the natural cortisol drop throughout the day.
Manage stress! Stress effects many things in your body, and this is not an exception. Stress raises your cortisol levels an unnecessary amount and keeps them high for prolonged periods of time preventing your body from relaxing into the restful and healing sleep. This causes irregularities in your natural rhythms.
Expose yourself to some morning sun. Exposure to early morning sunlight triggers the rise in cortisol levels to start the day and works to regulate the circadian clock.
Circadian rhythms are an important part of health, and with healthy lifestyle changes and sleep hygiene practices we can restore and regulate our natural body clock.
*Exciting update: Recent research has suggested that circadian rhythms were regulated in cells of organs isolated in petri dishes – this hypothesises the idea that the circadian rhythms are cellular rather than being controlled by the hypothalamus as previously thought!
