Natural blue light is emitted by the sun and it’s essential in regulating our circadian rhythm aka the sleep-wake cycle and body clock. It stimulates cortisol and suppresses melatonin production in the morning thus making us more alert. It also improves reaction time and a sense of wellness. In the evening, when the sun goes down, our body starts producing melatonin, the so-called sleep hormone.
Natural blue light is accompanied by all the other colours from the light spectrum, making it a healthy light source and body clock regulator. In countries where winter days are very short and dark, people often suffer from Season Affective Disorder, which lowers mood and heightens feelings of depression and anxiety.
So if blue light is healthy, why should we reduce exposure?
Unlike natural blue light from the sun, artificial light coming from digital devices and light bulbs are potentially harmful to human health because it contains far more blue compared to other colours in the spectrum. This excessive blue light penetrates the eye and over a day, will cause digital eyestrain. If you keep exposing yourself to it after the sunset, it will also reduce melatonin production and increase the release of adrenaline, dopamine, serotonin, and cortisol, which is the best recipe for insomnia and mental health issues.
Chronic excessive exposure to artificial light can cause:
Computer vision syndrome (eye fatigue, blurred vision, dry eyes, headaches)
Retinal cells damage and vision problems such as age-related macular degeneration
Sleep disruptions and insomnia
Depression and anxiety due to increased production of hormones like adrenaline, dopamine, serotonin, and cortisol
How to reduce blue light exposure
1. Reduce your screen time
This is the easiest strategy that won’t cost you a thing. If your work description entitles staring at a computer screen all day, don’t watch TV when you come home. Go for a walk, read or listen to audiobooks and podcasts. Beware that many household appliances also emit blue light through their displays. Don’t use digitally lit appliances three hours before bed and don’t use a digital clock in your bedroom.
2. Use blue light software and filters on your laptop and phone
Use blue light filtering software on your computer and turn the display on your smartphone red. Although the latter doesn’t have a strong scientific backing, it’s worth trying.
3. Wear blue light blocking glasses
Blue blocking glasses are our favourite bio-hack when it comes to controlling the circadian rhythm and protecting our eyes from strain. There are three types of blue light blocking glasses- blue blockers, blue reducers, and blue/green blockers. You wear blue reducers during the day to avoid eyestrain and headaches and the other two to three hours before sleep to prevent disruptions to your sleep-wake cycle.
BLUblox (blublox.com) are our favourite blue light blocking glasses. They are backed by science and made in Australia from the best quality materials. Find out more about the differences between blue light blocking glasses in their blog here.
4. Get in the sun!
Get outside at sunrise to let the brain set your body clock. Then get outside again at lunch for your second dose of full-spectrum natural light. The blue light wavelengths in sunlight help your brain maintain an optimal circadian rhythm including hormone production. Essentially, you want cortisol in the morning and melatonin at night.
5. Reduce blue light in your house
Another cheap and effective strategy is reducing blue lights in your house, especially in the bedroom. The bedroom should be only used for sex and sleep. Laptops, phones, tablets, TVs and any digital devices don’t belong there. To reduce blue light in the whole house, you can replace LED bulbs with blue light filtering light bulbs.
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Computer vision syndrome (CVS) is an umbrella term for a pattern of symptoms associated with prolonged digital screen exposure, such as eyestrain, headaches, blurred vision, and dry eyes.