Blue Light (from devices) and its Effects on our Eyes and Sleep

Blue light is a type of high-energy visible light with a short wavelength that is emitted from the sun as well as electronic devices such as smartphones, tablets, and laptops. While blue light from the sun is beneficial during the day because it boosts alertness, mood, and helps with cognitive function, it can disrupt sleep patterns due to its impact on melatonin production. In recent years, there has been growing concern about the potential negative effects of blue light emitted from digital devices on our eyes and sleep. ?

Effects of Blue Light on the Eyes

Blue light has the potential to cause damage to the eyes, especially with prolonged exposure or at high intensities. Studies have shown that blue light can affect the mitotic phase of corneal epithelial cells, which can lead to dry eyes. Blue light can also cause damage to the lens, leading to cataract formation. While the lens blocks blue light to protect the retina, it undergoes a decrease in transparency or color change, which can lead to cataracts. Additionally, blue light can cause glare or haze, especially in someone who might be developing cataracts. ?

Blue light can also cause damage to the retina, specifically the retinal pigment epithelium, by releasing cytokines that disturb the integrity of the retinal pigment epithelium (RPE)-choroid complex. It can also cause atrophy of the outer nuclear cells, which can disturb visual transduction. The French Agency for Food, Environmental and Occupational Health & Safety (ANSES) maintains that blue light from LEDs, including those in digital screens, causes adverse health effects. ?

However, there is currently no evidence that screen use and LEDs in normal use are harmful to the human retina. Research indicates that further studies are necessary to fully understand the long-term effects of blue light exposure. ?

Beyond its potential impact on eye health, blue light also plays a significant role in regulating our sleep patterns.

Effects of Blue Light on Sleep

Blue light suppresses the body's release of melatonin, a hormone that makes us feel drowsy. While this is beneficial during the day, it can be detrimental at night when we are trying to sleep. Exposure to blue light in the evening can trick our brain into thinking it is still daytime, disrupting circadian rhythms and leaving us feeling alert instead of tired. ?

Studies have shown that blue light exposure before bedtime can create circadian disruptions and inhibit melatonin secretion in the brain, which can lead to deteriorated sleep quality and duration. Sleep deprivation can have negative effects on mood, learning, memory, and academic performance. A meta-analysis reported students sleeping an average of approximately 7 hours per night with anywhere from 60%–80%...source There are a variety of sleep disorders that appear to be closely related to visual impairment, suggesting that sleep quality is related to eye diseases. ?

One study found that blue light exposure before bedtime reduced the ratio of deep sleep in healthy young men. Another study found that blue light exposure can decrease sleep quality and duration. Interestingly, some research has also shown that blue light can have positive effects on cognitive performance, alertness, and reaction time. This suggests that blue light may have different effects depending on the time of day and the individual. ?

Blue Light Filters and Their Effectiveness

There are different types of blue light filters available, including clear and amber-tinted lenses. Clear lenses filter only a portion of the blue light spectrum (about 400 to 440 nm), typically around 20% to 40%. Amber, blue light glasses filter more blue light, from about 400 to 480 nm. ?

Some blue light glasses have red or orange-tinted lenses that are designed to block more blue light. Yellow-tinted glasses are intended to block a narrow spectrum of blue light and may be a suitable option for daytime use. ?

One example of blue light filtering technology is BlockBlueLight Screen Time Computer glasses. These glasses use ClearBlue lens technology, which filters 50% of light throughout the entire 400 to 500 nanometers range while maintaining clear vision. The ClearBlue lens technology allows just the right amount of light to pass through to contribute to alertness, function, and good mental health. ?

The effectiveness of blue light filters varies depending on the type of filter and the amount of blue light it blocks. It is important to choose a filter that blocks the higher-energy wavelengths of blue light (380 to 450 nm) for maximum effectiveness. Studies have shown that reducing blue light with a filter by 50% could reduce retinal damage by 80%. ?

Best Practices for Using Electronic Devices

Practice

Description

Reduce screen time

The simplest way to reduce exposure to blue light is to limit the amount of time you spend using electronic devices.

Take breaks

If you must use a computer or other device, take regular breaks to look at something 20 feet away for at least 20 seconds every 20 minutes. This can help reduce eye strain and prevent your brain from thinking it is still daytime.

Use a screen filter

Applying a screen filter to your devices can help reduce the amount of blue light emitted from the screen.

Adjust screen settings

Many devices have a "night mode" setting that reduces the amount of blue light emitted from the screen. You can also adjust the brightness and contrast of your screen to make it more comfortable to view.

Use computer glasses

Computer glasses with yellow-tinted lenses can help filter blue light and ease digital eye strain.

Maintain a good working distance

Position your devices at least 30 inches from your eyes to reduce blue light exposure.

Control lighting and glare

Make sure your workspace is well-lit and that there is no glare on your screen.

Take supplements

Some studies have shown that taking supplements with lutein and zeaxanthin can help ease eye strain and improve sleep quality.

disclaimer: Do not take any supplements without consulting a doctor

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Conclusion

Blue light from electronic devices can have negative effects on our eyes and sleep. While more research is needed to determine the long-term effects of blue light exposure, it is important to take steps to minimize our exposure and be mindful of its potential effects on our health and well-being. By following the best practices for using electronic devices, such as reducing screen time, taking breaks, and using blue light filters, we can reduce the risk of eye strain, sleep problems, and other health issues. While blue light is a necessary part of our daily lives, it's crucial to be mindful of its potential effects on our health and well-being. By taking proactive steps to manage our exposure, we can harness its benefits while minimizing its risks.

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