Emerging studies suggest potential upsides and downsides to blue light blocking glasses. As research continues to evolve, what‘s needed is an evidence-based reference to help readers draw informed conclusions aligned with their doctor‘s advice. This overview article aims to provide that balanced, nuanced analysis.
What is Blue Light?
Before analyzing the promise and pitfalls of blue light blocking tech, it helps to understand what blue light is. The visible color spectrum that human eyes can detect ranges from violet light with short wavelengths, all the way to red light with longer wavelengths. Blue light sits squarely in the middle.
We used to get most of our blue light exposure from the sun. But in today‘s device-filled world, we also get artificial blue light from smartphone and computer screens, LED bulbs, and other electronics.
Natural blue light, like that emitted from the clear daytime sky, helps regulate healthy circadian rhythms. But some emerging research questions whether prolonged exposure to artificial blue light at night from devices might negatively impact sleep. More studies are still needed. Credit: Luis Villasmil.
The Origins of Blue Light Blocking Glasses
In response to concerns about excessive blue light exposure from electronics, innovators developed lenses that filter out more of the blue light spectrum. The first blue light blocking glasses emerged in the mid-2010‘s.
Brands market them as a way to reap benefits like:
- Alleviating digital eye strain
- Reducing headaches
- Improving sleep by limiting blue light exposure at night
But other experts argue blocking healthy exposure to natural blue light from daylight could also cause issues. Let‘s analyze some of the promising theories as well as areas requiring more research.
The Possible Upsides: The Case for Filtering Blue Light
First, let‘s review some of the potential benefits that proponents claim blue light blocking glasses offer:
Reducing Digital Eye Strain
It‘s true that many of us spend hours daily staring at phones, laptops, tablets and more. Reports of tired, strained eyes are also increasing.
Multiple studies suggest that excessive blue light exposure contributes to eye fatigue. Glasses that filter some of that intense blue light out may relieve this eye tiredness.
For example, research published in the International Journal of Ophthalmology in 2018 concluded blue light blocking lenses "showed significant efficacy" for improving eye comfort and vision compared to regular lenses during computer use.
Easing Headaches
If you get headaches after long days spent scrolling screens, blue light filtering may also help per some reports.
One study had people use electronic devices for up to 4 hours with either regular or blue light blocking glasses. Those wearing the blue light filtering glasses reported significantly fewer headaches.
So when it comes to digital eye strain and headaches, blue light blockers show promise. But what about sleep?
Better Sleep
Here‘s where things get more complex. Many brands market blue light blocking glasses as magic bullets for sleep troubles.
The underlying theory is sound: Research shows exposure to bright light at night, especially blue light, can suppress natural melatonin production and make it harder to fall and stay asleep.
- One study found using an eReader at night without blue light blocking glasses reduced participants‘ melatonin levels by over 50%.
So in theory, when worn at night, the glasses should improve sleep by filtering that disruptive blue light from your phones, tablets, and e-readers.
But not all studies have found such clear benefits when put to the test on actual sleep quality measures:
- A meta-analysis of 10 studies concluded blue light blocking glasses had "little to no effect on sleep quality."
Clearly more randomized controlled longitudinal studies are still needed to determine effects on sleep.
Protecting Eye Health
A final claimed upside is protecting eyes from possible damage caused by excessive blue light exposure over many years.
For example, some concerning research indicates blue light could contribute to macular degeneration later in life.
But more longitudinal studies over longer periods are still necessary to determine if blue light glasse prevent retinal damage over time.
So in summary:
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When it comes to digital eye strain and headaches, the best current research suggests blue light blocking glasses likely help.
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For sleep benefits, the science is still inconclusive despite the marketing claims.
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As for long term eye health protection, more longitudinal studies are needed.
Now let‘s dig deeper into why other experts argue avoiding blue light blocking glasses altogether may be wise…
The Potential Downsides: Why Limiting Blue Light Could Backfire
Recent concerning studies suggest completely filtering healthy blue light exposure long-term might cause issues like:
Circadian Rhythm Imbalances
Remember, our bodies rely on natural cycles of light from the sun to set our internal "body clocks." This circadian rhythm regulates crucial functions:
- Alertness & sleep cycles
- Mood
- Focus
- Energy levels
- Body temperature
- Hormone regulation
Healthy blue light exposure from daylight helps maintain these stable cycles. Yet some research indicates blocking blue light could disrupt our natural circadian rhythms even during daytime hours.
For instance, one small study had participants wear blue light blocking glasses for 3 hours during midday. Those who wore the glasses ended up secreting melatonin earlier in the evening than expected, indicating an abnormal shift in their circadian cycle.
Problems With Mood Regulation
Related to impacts on internal body clocks, depriving ourselves of healthy blue light exposure might also hamper mood regulation:
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Studies confirm bright blue daylight triggers the brain to produce serotonin, dopamine and other "feel good" chemicals that regulate our emotions.
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There are even FDA-approved "light therapy boxes" that help treat seasonal depression with healthy blue light exposure.
So if worn over long periods, blue light blockers may interfere with some of these natural mood and emotion regulatory processes that require blue light as an environmental cue.
Lower Vitamin D Production
Here‘s another issue with excessive use of blue light blockers: they prevent our bodies from naturally producing sufficient vitamin D through sunlight exposure.
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You see, the UV rays in sunlight react with oils in our skin to trigger vitamin D synthesis.
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But studies show blue light also plays an assisting role in this process.
Less blue light reaching our eyes can mean lower vitamin D levels as a result.
In one study, people wearing blue light blocking glasses while exposed to UV rays from the sun ended up producing significantly less vitamin D than those without the glasses.
Deficiencies in this crucial vitamin are already widespread. So excessive use of blue light blockers year-round could worsen this issue.
In summary, potential downsides include:
- Circadian rhythm disturbances
- Impacts to natural mood regulation
- Reduced vitamin D production
The risks above focus on extended, excessive use of blue light blockers. But what about more moderate use aligned to each individual‘s needs?
Personalized Use: The Best Path Forward
Rather than take an all-or-nothing view, a more nuanced approach based on each person‘s lifestyle and environment may be wisest:
For those with excessive full-spectrum light exposure at night from screens and devices, blue light filtering glasses could provide real sleep benefits without the downsides from daytime use.
But for office workers deprived of natural light all day or night shift workers constantly awash in indoor lighting, blocking even more healthy blue light from any midday sunlight might be detrimental.
The healthiest approach likely lies somewhere in the middle: Avoid overdoing use of blue light blockers without forgoing their potential benefits altogether when used judiciously.
Discussing options with your eye doctor or sleep specialist based on your individual situation is wise rather than relying on generic mass-market advice.
They can help determine if occasional use, prescription strength or lens coatings might suit your needs while considering any pre-existing conditions.
Key Takeaways: Who Might Benefit Most From Blue Light Blockers?
Given the double-edged nature of the research, who stands to gain the most from blue light blocking glasses used prudently?
- Those exposed to excessive blue light from screens late into the evening, negatively impacting sleep. But only use glasses selectively at night.
- People suffering chronic digital eye strain or headaches during daytime device use.
- Night shift workers on abnormal sleep/wake cycles awash in artificial indoor lighting.
For these groups, blockers could filter the most disruptive light spectrums without interrupting healthy exposure long-term.
But unless facing excessive nighttime blue light disturbance related to screens, the average person likely gets more upside than downside from naturally occurring blue daytime light. Limiting that could backfire.
In the end, people should make individual choices based on lifestyle needs and in discussion with their doctor.
There are also other ways to be smart about blue light, like installing blackout shades in the bedroom, enabling warmer nighttime screen settings, taking regular screen breaks and more.
The Bottom Line
Based on current evidence surrounding emerging blue light research:
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Potential benefits like reduced eye strain and headaches exist from blocking excessive artificial blue light exposure during the day.
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Judicious use at night also holds promise for better sleep by preventing screens from suppressing melatonin production.
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But blindly over-wearing blue light blocking glasses year round without considering healthy sun exposure needs may be unwise.
Rather than adopt yet another unnecessary "wellness trend" claiming exaggerated benefits, have candid discussions with your eye doctor or sleep specialist. Together decide if occasional, selective use of blue light blockers makes sense based on your lifestyle and environment.
FAQs
Who needs prescription blue light blocking glasses?
Rather than rush out for prescription blue light blocking lenses without context, have an open conversation with your eye doctor first. Discuss your typical light exposure from devices and screens, sleep habits, pre-existing conditions, and more. Together determine if coating lenses or wearing filtering glasses only during select activities makes sense for your situation.
Don‘t device screen settings remove the need for glasses?
Many devices today offer built-in "Night Shift" type screen modes that cut down on emitted blue light. While helpful, the benefits likely don‘t match dedicated glasses. Consumer Reports testing found blue light blocking glasses to filter 2-4 times more high-energy blue light than iPhone Night Shift settings alone. But for mild cases, built-in screen modes might provide sufficient relief.
Can children wear blue light glasses?
Research on blue light blocking glasses specifically for children remains limited. While many manufacturers market kid-friendly options claiming benefits, consult your pediatric eye doctor or sleep specialist first before putting young children in filtering eyewear day in and day out. Together evaluate actual need based on your child‘s lifestyle and environment.
