Do blue light glasses work? Generally speaking, yes.

Do blue light glasses work? Generally speaking, yes.

For many people, blue light filtering glasses can increase comfort.

Blue light glasses offer one of a handful of ways you may be able to improve your visual comfort in front of digital screens. People primarily use them during extended screen sessions, when they’re exposed to LED blue light for hours at a time.

Blue light glasses feature special light-filtering technology that prevents a certain percentage of blue light from reaching the eyes.

These FAQs will provide a better understanding of what blue light is, how glasses can filter blue light and why it's a good idea to wear blue-violet light filtering glasses.

What is blue light?

All of the light we see falls somewhere along the rainbow-colored visible light spectrum.

The light of each color has a different wavelength. Blue light is on the lower end of the spectrum, with wavelengths between about 380 and 500 nanometers.

Light with shorter wavelengths has higher energy. So, blue-violet light is also called high-energy visible (HEV) light.

Digital electronic devices emit blue light.

Digital screens, like the ones on our phones, TVs and computers, also emit blue light. 

What does blue light from sunlight do to your eyes?

The sun is the largest producer of blue light, even indoors. Scattered blue light in the atmosphere is what makes the sky look blue.

Blue light can be separated into blue-violet light (about 400-455 nm) and blue-turquoise light (about 450-500 nm). Blue-violet light — HEV ( high-energy visible) light — is in the potentially harmful range, and the longer wavelength blue-turquoise light is lower energy and what impacts sleep/wake cycles. 

When blue-turquoise light enters your eyes (especially late in the day), it sends a signal to your brain to stay awake by disrupting the production of the natural hormone melatonin. When melatonin production is out of whack, so is your sleep schedule.

It’s possible that overexposure to HEV blue-violet light from the sun might damage the retinas of your eyes over time, leading to sight-threatening diseases like macular degeneration.

Is blue light from the sun bad?

Yes and no — blue light can be both good and bad.

Blue light is a little like UV radiation. The sun’s UV rays can be a great thing in moderation, leading to healthy vitamin D levels and overall well-being. But if you overdo it, you could experience damage to your skin and eyes.

Blue-turquoise light is one of the primary elements regulating circadian rhythms (sleep cycles). Blue-turquoise light from sunlight tells the brain to stay awake. But too much blue light (especially late in the day and before bedtime) may interrupt your sleep cycle.

Researchers at Harvard found that 6.5 hours of blue light exposure had twice the negative impact on sleep cycles when compared to the same amount of exposure to green light.

The amount of blue light emitted from digital screens is very small compared to sunlight. We don’t know for sure whether long-term digital blue light exposure can impact the eyes or not. But people are spending more time than ever staring at screens, and wearing blue light filtering glasses can increase visual comfort.

SEE RELATED: What is computer vision syndrome?

Do blue light glasses filter all blue light?

They can, but they usually don’t — and for good reason.

Blue-light glasses that are clear usually filter only blue-violet light, not blue-turquoise light. A dark orange or amber tint is required to filter some blue-turquoise light. 

Lenses that filter a large portion of blue light, including blue-turquoise light, have a deep orange or amber tint, greatly changing the way everything looks around us.

However, lenses with 10% or 20% filtering can appear almost clear. These usually make more sense for all-day wear. Many computer- or gaming-specific glasses have visibly yellow lenses, since they tend to filter around 50% or 60% of blue light.

You may want to experiment with different levels of filtering to see what works best for you.

Can you wear blue light glasses all day?

Yes, filtering blue light all day will not hurt your vision.

But be aware that filtering too much blue-turquoise light from the sun may have the reverse effect on your alertness, making you feel groggy earlier in the day. This is especially true for high-percentage lenses.

If you feel more tired wearing high-percentage blue filtering glasses, consider stepping down to a lower percentage.

What’s the difference between blue light glasses and computer glasses?

Most computer glasses are also blue light glasses, but not necessarily the other way around.

Computer glasses usually have a higher degree of LED blue light filtering plus slight magnification to increase comfort. Computer glasses with magnification act like reading glasses, except they optimize intermediate-distance vision instead of near vision, and they may also have blue light filtering.

If these specialized glasses work for you, the additional comfort can translate into increased work productivity.

Gaming glasses also tend to include slight magnification and mid-range blue light filtering.

Clear everyday blue light glasses may be better for general use. These lenses filter blue-violet light and offer more flexibility in terms of style and facial fit.

If you're not sure how to find the best computer glasses for your needs, it's always a good idea to consult with your eye doctor.

Are there ways I can reduce eye fatigue?

Absolutely. Free programs like f.lux or your phone’s “night shift” and dark modes can also reduce the amount of blue light that reaches your eyes.

Computer glasses with magnification can reduce digital eye strain that can be caused by focusing on the small print of a screen for long periods of time, producing symptoms like headaches, squinting, dry eyes and blurry vision.

Practicing the 20-20-20 rule is another great way to reduce computer eye strain: For every 20 consecutive minutes of screen time, take a quick break and look at an object 20 feet away for 20 seconds. This gives the tiny muscles inside your eye a well-deserved break.