What is Circadian Misalignment?

Circadian rhythms are patterns in physiology and behaviour which run on a cycle of around 24 hours, driven by an internal clock. The demands of our hectic modern society can cause our internal rhythms to become out of sync with our environmental cycles as well as becoming misaligned with one another. The term ‘circadian misalignment’ applies to a whole range of circumstances, one of which is when our sleep/wake cycle becomes out of sync with the day and night cues of our environment. With holiday season under way, a relevant example of this is jet lag… so let’s find out more.

Jet lag occurs when our sleep/wake cycle is in sync with the time zone of our original location and is therefore misaligned with the day and night cycle of our destination. Symptoms of jet lag include difficulties falling asleep at night and staying awake during the day, issues with concentration and even digestive problems.

One method of reducing the symptoms of jet lag is to try to adjust your internal clock towards the destination time zone before travelling and light therapy can be a powerful tool! There is no one-size-fits-all method for achieving this, and the schedule that you follow will be dependent on multiple factors including your current sleep/wake schedule and the sleep/wake schedule that you intend to have whilst in the new time zone, the number of time zones which will be crossed during your flight and the number of days available to try to adapt. See guidance on adjusting your sleep/wake cycle ahead of travel here.

We have all heard of jet lag, but what about social jet lag?

Social jet lag occurs when our internal rhythms become out of sync with cycles of our society, often due to social commitments such as work. Due to habitual misalignment of their internal rhythms and actual sleep/wake times, shift workers experience social jet lag which causes symptoms similar to that of jet lag due to long haul travelling. It is suggested that as well as the circadian rhythms of shift workers being out of sync with the light/dark cycle of their environment, the circadian disruption caused by their working schedules may also cause various levels of the internal circadian system to become out of sync with one another. Because of this, shift work has been associated with various health issues including metabolic health, heart health, mental health and cancer.

Light is the most powerful synchroniser of our circadian rhythms, and when they become out of sync, light therapy can be an effective tool for regulating them. Bright light therapy works by mimicking natural daylight, stimulating the brain and suppressing the production of melatonin, the hormone which is conducive to sleep. When sleep and waking does not align with the light cues of the environment, for example in the case of shift workers, bright light therapy can help to regulate the internal rhythm. A daily session of bright light therapy upon waking can help to boost mood, energy and alertness, leaving you feeling refreshed.

Dawn simulation also helps you to feel ready for sleep and to wake much more gently than with a regular alarm. Lumie wake-up lights offer an effective solution for unwinding at bedtime, whatever time that may be, and waking gradually, whether that is in the morning or in the middle of the night. The sunrise and sunset features of these lights stimulate appropriate hormones through light. Fading light is a natural cue for the body to increase the production of the sleep hormone, melatonin, allowing you to wind down and feel ready for sleep. When it is time to wake up, the sunrise feature of Lumie wake-up lights activates with gradually increasing levels of light, prompting the suppression of melatonin production and allowing you to wake feeling rejuvenated.

So, whether you're preparing for a long haul flight or are looking to make your sleep and waking a little easier, Lumie light therapy lamps are a trusted companion!

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