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The power of light: Tool for recovery, improved mental health and quality of life

Here in Dunedin we know all about dealing with dark cloudy days, given we have the lowest mean annual number of sunshine hours in the country – 1590 (in contrast to Auckland’s 2066). We also know well what a boost a few days of warm sunny weather can bring.


The Circadian Rhythm

It is not surprising that sunlight has such a strong effect on the way we feel. Light is the most important zeitgeber (regulator) of our circadian rhythms – our body’s master clocks. Special receptors in your eyes transmit signals to this master clock that in turn regulates your sleep-wake cycle, metabolism, alertness and levels of energy, enabling you to be in sync with the environment. Work on circadian rhythms even received a Noble Prize in Physiology or Medicine this year.

Change in sunlight during the day

An important thing to note is that sunlight is not uniform throughout the day; there is a spike of blue light in the morning, white light during the day, while the sunsets are in the yellow, orange and red ranges. These changes influence production of the sleep hormone melatonin. Exposure to bright blue and white light from smartphones, laptop and TV screens in the evening suppresses melatonin production, which delays sleep onset and negatively impacts sleep quality.


Poor sleep leads to poor health

Circadian rhythm misalignments and associated poor sleep may lead to a vast array of health problems, such as obesity, diabetes, decreased cognitive performance, decreased memory consolidation, increased fatigue and atherosclerosis.

The sick and elderly are more susceptible to circadian rhythm deregulations, and unfortunately, hospital environments are frequently reported to contribute to poor sleep quality. Constant uniform artificial hospital light may have a negative effect on patients’ quality of sleep, recovery and overall quality of life.


The Innovation Award

A project proposed by Kristina Aluzaite, a researcher at the Department of Medicine, is aiming to tackle this exact problem. She is proposing to install naturalistic lights that would mimic the natural variation in sunlight in patients’ wards, which would allow them to restore and stabilize healthy circadian rhythms and get a good night’s sleep.

From Left: Southern Innovation Challenge CEO award winner Kristina Aluzaite, staff priority award winners Layla Hehir and Ohad Dar, and Southern DHB CEO Chris Fleming

The idea received the Southern Innovation Challenge CEO award and 7,000 NZD to trial in the Southern DHB setting. If proven successful, this method will be considered for the new Dunedin hospital. Read more about other winning Southern Innovation projects.


Naturalistic light may be the solution

There has been a lot of research done showing that patient rooms with more natural light decrease hospitalization duration and even decrease mortality rates. Using naturalistic lights to decrease circadian-rhythm-misalignment-related health impact is a new concept, and only a handful of hospitals around the world have explored this option. A recent Danish study reported significant decrease in depression, fatigue and increase in sleep quality in the patients.

In a nutshell, bright morning light is required to awaken the body, uplift energy and mood during the day, while filtering that light out towards the evening allows the body for prepare for a quality night’s sleep.


Benefits for staff

This approach is also likely to have large benefits to the members of staff, by increasing productivity, alertness, improving quality of life, and having fewer negative effects on the night-shift workers.


Follow for more updates.

If you want to find out more about the project, contact @MontaneHat


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