We all take special care to protect our eyes from the sun’s harmful UV rays; but what about the harmful effects of blue light rays?
Usage of blue light emitting gadgets before bedtime prolongs the time it takes to fall asleep, delays the circadian clock, suppresses levels of the “darkness hormone” melatonin.
Sources of blue light include the sun, digital screens (TVs, computers, laptops, smart phones and tablets), electronic devices, and fluorescent and LED lighting.
As the day progresses, we actually move closer to the back lit devices
Impact on Sleep:
Digital Screens emit blue light which are so bright that at night, brain gets confused by that light. Blue wavelengths—which are beneficial during daylight hours because they boost attention, reaction times, and mood—seem to be the most disruptive at night. This causes the brain to stop producing melatonin, a hormone that gives body the “time to sleep” commands. Because of this, digital screen light can disrupt sleep cycle, making it harder to fall and stay asleep.
Changes in sleep patterns can in turn shift the body’s natural clock, known as its circadian rhythm. Studies have shown that shifts in this clock can have devastating health effects because it controls not only our wakefulness but also individual clocks that dictate function in the body’s organs. Research also shows that it may contribute to the causation of cancer, diabetes, heart disease, and even obesity.
Eyes and Blue Light:
The visible wavelengths – which include the harmful blue wavelengths – pass right through the pupil and are absorbed by the retina. When blue light hits the retina, its high energy mixes with oxygen creating a destructive force that destroys photoreceptor and retinal pigment epithelium cells (RPE). Over time, this process can lead to Age‐related Macular Degeneration, (AMD).
- Eye redness or irritation
- Dry eyes due to reduced blinking
- Blurred vision
- General fatigue
- Back pain
- Neck pain
Parents take a note: Children are at high risk when it comes to the negative effects of exposure to blue light
Children and teenagers (ages 8-18) spend around 7 hours a day consuming electronic media in today’s increasingly technological society. Blue light is extremely damaging for kids as for children their eyes are still developing, and they may not have the protective pigments in their eyes to help filter out some of this blue light.
For children aged 2-4 screen time should be limited to less than 1 hour per day. For children aged 5-11 and 12-17 less than 2 hours of screen time per day.
- An effective way to avoid or help to resolve digital eye strain is to follow the “20-20-20 Rule” — every 20 minutes, stare at something at least 20 feet away for at least 20 seconds
- Use dim red lights for night lights. Red light has the least power to shift circadian rhythm and suppress melatonin.
- Avoid looking at bright screens beginning two to three hours before bed.
- Use orange tinted blue light blocking glasses also called blue blockers to counter such light effects. They filter out the short wavelengths in the blue range portion of the spectrum.
- LEDs with an emission peak of around 470–480 nm should be preferred to LEDs that have an emission peak below 450 nm.
- Download a light-reducing app like f.lux
- Ensure your child has computer glasses to wear that have a blue-blocking coating while they are on devices to prevent the blue light from entering their eyes.
- Expose yourself to lots of bright light during the day, which will boost your ability to sleep at night, as well as your mood and alertness during daylight.