Are Blue filter lenses worth the extra cost for your eyeglasses?
The Power of Blue Light to Energize Your Day
Dear Readers,
Welcome to Science Simplified, a newsletter which Unlocks the Wonders of Science, One Simplified Concept at a Time!
Recently, while waiting for an eye exam, I found myself observing the people around me to pass the time. I noticed a common trend: each person was being encouraged to opt for blue filter lenses, with reasons given such as preventing eye strain, dryness, and shielding against harmful blue light emitted by screens. Considering screens have become ubiquitous in our lives, this reasoning seemed to resonate with everyone.
What surprised me was that none of the individuals declined the blue filter for their lenses! This observation inspired me to write this article. Are people truly unaware of the potential benefits of blue light or are we falling prey to what can be termed as 'fear marketing'—a strategy that targets our primitive fear response center, the amygdala, leading us to make emotional rather than intellectual decisions?
In this article, we will explore different scientific studies to holistically understand whether opting for blue filter lenses for our prescription glasses is advantageous or merely an additional expense added to an already inflated fees.
Let’s start with basics:
What is blue light?
Blue light is a high-energy, short-wavelength light within the visible spectrum. It is emitted naturally by the sun and also artificially by digital screens and LED lights.
What happens when blue light enter your eyes?
Light enters the eye through the cornea, the transparent outer covering and hits the retina at the back of the eye. Retina contains photoreceptors called cones and rods. Cones are responsible for color vision and high-resolution detail while rods take care of peripheral vision and night vision. Besides rods and cones, our eyes also contain specialized cells called melanopsin-containing retinal ganglion cells (mRGCs). Melanopsin is a photopigment found in these cells, which is particularly sensitive to blue light. When exposed to blue light, melanopsin is activated which controls the master biological clock and in turn your sleep-wake cycle.
Let’s simplify it:
The Master Biological Clock, located in your brain, acts like your body's own timekeeper. It manages your internal clock, which controls when you feel awake and when you feel sleepy, among other things like your body temperature and hormones.
Light, especially blue light, is like a signal for your body clock. When you're exposed to blue light during the day, it tells your body it's time to be awake and active. This light switches off the sleepy hormone called melatonin and helps your body produce cortisol, which gives you energy.
At night, when there's less blue light, your body gets the signal that it's time to wind down. Without blue light, melatonin production starts up again, helping you feel sleepy and ready for bed.
So, blue light plays a big role in keeping your body's internal clock in sync with the natural day and night cycle, helping you feel alert during the day and ready for sleep at night.
What are Blue filters for Eyeglasses?
Blue filter is a special type of lens coating or material designed to reduce the amount of blue light that reaches your eyes when you wear glasses. These filters work by selectively blocking or absorbing a portion of the blue light emitted by sun, digital screens, LED lights, and other sources.
Why blue filters are suggested?
Reducing Eye Strain: Prolonged exposure to screens, can lead to digital eye strain or computer vision syndrome. Symptoms may include eyestrain, dry eyes, headaches, blurred vision, and difficulty focusing.
Improving Sleep Quality: Exposure to blue light, particularly in the evening and nighttime, can disrupt the production of melatonin, a hormone that regulates sleep. By reducing evening exposure to blue light, either through blue light filters on glasses or by using screen filters on electronic devices, you can help maintain your body's natural sleep-wake cycle and improve sleep quality.
Protecting Eye Health: While more research is needed, some studies suggest that prolonged exposure to blue light may contribute to retinal damage and increase the risk of age-related macular degeneration (AMD), a leading cause of vision loss.
Let’s dissect the evidences based on Scientific Studies:
Multiple studies have found associations between increased screen time and symptoms of eye strain, including dryness, discomfort, and fatigue. The research on the role of blue light in causing eye strain is still evolving, and while there is evidence suggesting a link between blue light exposure and symptoms of eye strain, the findings are not yet conclusive.
While blue light emitted by screens may contribute to eye strain, it's just one of several factors. Extended periods of screen use often lead to reduced blinking, which can exacerbate dryness and discomfort. Encouraging regular blinking to maintain adequate tear film and eye moisture and taking breaks to rest the eyes can help alleviate this issue. Following the 20-20-20 rule (taking a 20-second break every 20 minutes to look at something 20 feet away) is a recommended rule of thumb. Factors such as screen brightness, glare, viewing distance, and individual visual habits significantly impact eye strain. Adjusting screen settings, using anti-glare filters, maintaining an appropriate viewing distance, and practicing good posture can all contribute to reducing eye strain. Blue light filters on screens is another good strategy.
Blue filter glasses can be beneficial if you wear them only in the evening. Here's why: In the evening, our bodies get ready for sleep, and exposure to blue light can interfere with this process. Blocking or reducing blue light can help preserve our natural sleep preparations. However, we still need blue light during the day to kickstart our wakefulness. Wearing blue filter glasses all day might mean missing out on these beneficial daytime effects of blue light, which could disrupt your sleep-wake cycle. It's essential to use blue filter glasses thoughtfully to maintain a healthy sleep rhythm.
What is the role of blue light filters in protecting eye health?
Blue light filters, like those found in glasses or screen protectors, are still being studied to see if they can help protect our eyes, especially against conditions like age-related macular degeneration (AMD). While some studies suggest they might help by reducing exposure to strong blue light from screens, we're not sure yet.
For AMD, some studies suggest that certain nutrients like vitamins C, E, and zinc, as well as lutein and zeaxanthin, found in foods or supplements, might help slow down its progression in people at high risk. But it's important to talk to a healthcare provider before starting any supplements because they might not be safe for everyone.
Lastly, staying active with regular exercise can also be good for overall health and might lower the risk of AMD. Try to get at least 150 minutes of moderate-intensity exercise each week, as recommended by health guidelines.
Final Judgement!
The solution is to use glasses with a blue filter specifically during the evening and night. In the morning and during the day, opt for glasses without a blue filter to allow the beneficial effects of blue light for wakefulness.
If using different glasses is not feasible, another option is to utilize the night shift/ night mode feature available on digital devices. Night shift mode or Blue light filter mode reduces the amount of blue light emitted by screens, which can help prevent disruption to your sleep cycle. This adjustment can be particularly useful in the hours leading up to bedtime when exposure to blue light should be minimized to support better sleep quality.
To enable the blue light filter, often called Night Shift on iPhones and Night Mode on Android devices, follow these steps:
iPhone (Night Shift):
Open the Settings app.
Scroll down and tap on "Display & Brightness."
Select "Night Shift."
Toggle the switch next to "Scheduled" to turn on Night Shift.
You can customize the schedule or adjust the color temperature to your preference.
Android (Night Mode):
Open the Settings app.
Look for "Display" or "Display & Brightness" settings.
Locate and tap on "Night Light," "Night Mode," or "Blue Light Filter."
Toggle the switch to turn on Night Mode.
You can usually customize the schedule or intensity of the blue light filter to suit your preferences.
Summary
In conclusion, while scientific research on the impact of blue light on eye health remains ongoing and inconclusive, studies have highlighted its association with disturbances in the sleep-wake cycle and inhibition of melatonin production, potentially affecting sleep quality. When considering the use of blue light filters for your lenses, it's important to weigh the potential benefits against their limitations. While blue filters may offer some relief from eye strain and discomfort, they are not a foolproof solution and should be used thoughtfully. Remember, maintaining good screen habits and overall eye health practices is key to protecting your eyes from the adverse effects of prolonged screen use.