Blue Light and Sleep
Sleep is instrumental to health. I've talked about this a lot (check out our blog on sleep if you have not yet read it).
Evidence abounds on the impact of blue light on the quality and quantity of sleep. While blue light exposure during the day can boost alertness and mood, exposure to blue light after sunset can affect your ability to both fall and stay asleep.
There are a number of considerations to the effect of blue light (the kind emitted from electronic devices) and sleep patterns. Ganglion cells in the retina of the eye act as receptors for light and are connected to the suprachiasmatic nucleus (aptly named the master clock) in the brain. Light is so effective at setting the body’s internal clock that the best way to overcome jet lag is to get out in the sunlight as soon as you can when you arrive at your destination. As the day ends and it starts to get darker, the ganglion cells signal to the brain that it is time to start making melatonin thereby lowering your body temperature in preparation for sleep.
In short, exposure to artificial light has screwed with the natural response. Not all light is created equal. Ganglion cells are especially sensitive to blue light (the kind emitted from computer screens and other electronic devices and LED light bulbs). Blue wavelengths in natural light help improve attention and mood helping you stay awake during the day. In fact, the fastest way to wake up in the morning is to look at a bright computer screen (a good tip if you are trying to trick your jet-lagged brain). When you are exposed to these blue wavelengths at night it disrupts the body’s release of melatonin which in turn affects the amount of REM sleep you receive.
There are a number of things you can do to reduce the effect of blue light on sleep:
Get in sync with the natural cycle of light (day) and dark (night) which stimulates sleep in diurnal (night-sleeping) animals. Sunrise, high noon and sunset act as milestones for the body’s natural clock (known as circadian rhythm). Getting out into the sunlight at these times of the day helps to set our body clock and prime ourselves for sleep
Minimise the use of electronics after sunset
If you do need to use your device after dark, many laptops, smartphones and tablets offer a blue light shield that you can set to increase the warmth of the colour thereby filtering out the blue light (such as the night mode on Apple devices where you can schedule night mode to automatically change the spectrum of the display. On an Apple device, go to Settings > Display > Night Shift and choose the warmthness setting and move it to “More Warm” between sunset and sunrise)
Get some glasses that block blue light (I have a pair from Baxter Blue - https://www.baxterblue.com.au/ - that are both stylish and functional) and use them if you need to work on a screen after sunset. Glasses of this type can block up to sixty per cent of the blue light from your electronic screen
