Do you need blue light glasses?

Does it seem like everyone is talking about blue light these days? There’s a reason for it. If you’re reading this on one of your screens (smartphone, laptop, tablet), you’re exposing your eyes to blue light now, though that might be a bit simplified.

Blue light is just one color on the light spectrum that we’re exposed to on a daily basis.

Even the sun and indoor lights have some level of blue light, it’s just a matter of figuring out how to manage it.

But back to the screens for a minute. As we spend more time staring at monitors, iPads, and smartphones, we increase the amount of blue light we’re exposed to — and that’s where blue light filtering glasses might help.

What is blue light anyway?

For starters, blue light doesn’t actually appear blue to the naked eye.

“Blue light is the portion of the visible light spectrum with the shortest wavelengths (400 to 500 nanometers or nm) and with the highest energy, hence it is often referred to as high-energy visible (HEV) light,” according to Dr. David Friess, OD, FAAO, of the Eyesafe Vision Health Advisory Board.

The eye does not block blue light well. The cornea and lens block UV rays from reaching the back of the eye (the retina). Blue light passes through these structures and can reach the retina.

Blue light exposure may increase the risk of macular degeneration and does contribute to digital eye strain.

“There are also two primary domains of blue light highlighted,” Friess says. One kind of blue light damages cells of the retina, while other blue light affects our wake/sleep cycle."

This “good” blue light “appears to contribute to physical and emotional health,” he says.

What does blue light do to your eyes?

Blue light is everywhere, and it can throw off our natural body clocks.

“We get constant exposure to blue light from ambient sunlight, computer screens, tablets and mobile phones,” said Dr. Rohit Varma, MD, MPH, founding director of Southern California Eyecare and Vision Research Institute.

“The brain associates blue light as daytime, so if a person is exposed to blue light for long periods of time during the night, blue light makes it more difficult for us to fall asleep at night and wake up in the morning,” Varma said.

While there’s no definitive information on the exact amount of blue light you can be exposed to before showing serious side effects, “long-term exposure to screen light can have some intense serious side effects,” said Caroline Dubreuil, product marketing manager for EyeBuyDirect.

“Headaches, disorientation and loss of sleep are just the start of it” said Dubreuil, whose website, like many eyewear retailers, sells blue light blocking glasses.

Benefits of blue light eyeglasses

All that screen time may be causing digital eye strain.  

“There are many causes for eye strain,” said Dr. Raj K. Maturi, MD, a spokesman for the American Academy of Ophthalmology. “Blue light is just one of them.”

Maturi said being too close to your screen doesn’t help: “We strain our eye muscles when looking at such a close target.”

Late-night screen time throws off sleep patterns, because blue light affects melatonin (the sleep hormone) levels.

How? Decreased light at night signals the body to generate sleep hormones like melatonin. Blue light disrupts these signals, and less melatonin is generated.

For some, blue light filtering glasses are a great way to combat the eye strain and sleeplessness that come with excessive screen time.

How do blue light eyeglasses work?

“Blue light lenses filter out blue light by blocking the transmission of a specific segment or range of wavelengths,” said Dr. Sheri Rowen, MD, FACS, of the Eyesafe Vision Health Advisory Board.

In addition to actual filtering, Rowen says “the lenses are designed to help reduce the occurrence of digital eye strain and avoid circadian rhythm cycle disruption, affecting sleep and overall well-being.”

The blue light lenses are usually a pale yellow tint (if you can see any color at all) and block harmful blue light, while modulating the wavelength impacting circadian rhythm.

Do you need blue light glasses?

Maybe. “The average time on devices and in front of screens for adults is pushing 11 hours per day, and as such, our eyes are under a lot of digital light strain,” Rowen said.

Even if you don’t need glasses to see clearly, Dubreuil believes it’s a good idea to always wear blue light blocking glasses when using digital devices.

If you spend a lot of time looking at your phone at night, blue light glasses might help you.

“Digital screens are major sources of blue light, specifically the kind of blue light our bodies use to regulate our sleep,” Dubreuil said.

“Whenever we use our digital devices, especially late into the night, we’re actually telling our brains to keep our bodies awake." 

Dubreuil added, “Research shows that wearing light filtering glasses 3-4 hours before bedtime can lead to better and more restful sleep."

Where can you find blue light filtering glasses?

“The best first step is to consult with an eye care professional who will help ascertain your needs for protection,” Rowen said.

She also advises an annual comprehensive eye exam to maintain overall eye health.

If you choose to buy blue light glasses online, do some research. Check reviews, return policies and most of all, make sure the lenses block harmful blue light.

NEED AN EYE EXAM? Find an optician near you and schedule an appointment.

What to look for in blue light glasses

When purchasing blue light glasses, Rowen recommends keeping an eye out for a certificate that specifies the wavelength range that’s filtered.

“For blue light filtering, this range should at least cover up to 455 nanometers,” she says.

Other ways to block blue light

If you’re still on the fence about blue light filtering glasses, you can try apps or settings built into your phone.

Maturi reminds us, “Most phones have some sort of a nightlight option. The phone screen changes imperceptibly over a few hours, and this keeps the melatonin levels going the right way.”

You can also try a program like F.lux which is free to use and adjusts your screen color according to the time of day.

For a small investment you can try Iris, which has more customization options.

There are also blue light screen filters that fit directly over your monitor, and blue light filtering lightbulbs that automatically filter out blue light at night.

Photochromic lenses are another eyeglasses option. Light adjusting lenses block both the sun’s harmful ultraviolet rays and blue light rays — and they can be worn inside and outside, day and night.

Other causes of digital eye strain

In summary, proper use of blue light filtering glasses and “sleep aware” apps on your devices can reduce blue light transmission to visual system. Blue light is certainly not the only contributor to the digital eye strain that so many experience today.

Accommodative or focusing issues, problems with eye tearing and dry eye syndrome are other conditions that contribute to digital eye strain.

“When we’re looking at our screens, we don’t blink as much,” Maturi said, and our eyes can become tired, blurry and dry as a result.

Maturi recommends the 20/20/20 approach: “Every 20 minutes, look 20 feet away for 20 seconds. This allows the eyes to come back to normal.”

Use of spectacle technology and digital apps can work to decrease blue light exposure and digital eye strain.

As participants in this digital age, we must also consider the need to achieve balance with use of digital devices and know that the simple act of decreasing use and exposure can also play a role in visual health.

The key takeaway: Do you need blue light glasses? Maybe.

The way you choose to protect your eyes from harmful blue light isn’t as important as consistently doing just that.

SEE RELATED: Computer eye strain: 10 steps for relief

Page published on Monday, 6 July 2020