Do Blue Light Glasses Work?

Quick Summary (What Does Science Say?)

Blue light blocking glasses sales have skyrocketed in the last few years. Especially in 2020, with the COVID-19 pandemic increasing digital screen time for people of all ages. 

Companies that produce blue light glasses (also called computer glasses), such as Zenni and Warby Parker, claim that these lenses can improve your lifestyle. Their two central claims are:

• Reducing blue light exposure can help combat digital eye strain (aka computer vision syndrome)
• Blocking blue light will increase your quality of sleep by helping regulate your circadian rhythm

But what does science say about these claims?

Digital Eye Strain

According to the American Academy of Ophthalmology¹ and multiple studies,^{2, 3, 4} blue light from digital screens has little to no effect on digital eye strain symptoms. More research is needed to draw conclusions, but it is unlikely that blue light blocking lenses can help reduce symptoms of digital eye strain.

Circadian Rhythm

Multiple studies have linked exposure to blue light with decreased melatonin levels and poor sleep quality.^{5, 6} More studies have shown that blue-light blocking glasses may provide a viable method for preventing melatonin suppression and increasing sleep quality.^{7, 8} Again, more research is needed to prove these theories. However, it seems likely that blue light blocking lenses have the potential to help improve your body’s circadian rhythm.

What is Blue Light?

Blue light comes from digital screens, the sun, fluorescent lighting, and LED lighting. It contains the most energy of all visible light. Invisible light, also known as ultraviolet or UV, has even higher energy levels and is proven to cause eye diseases.^{9, 10, 11} However, no harmful UVA or UVB light is emitted from computers, tablets, lamps, or TV monitors.¹²

Blue Light & Circadian Rhythms

Blue light plays an important role in your circadian rhythm. Exposure to sunlight throughout the day helps synchronize your body’s internal clock and natural processes.¹³ These processes include your wake/sleep cycle, cardiovascular system (heart rate, blood pressure, etc.), and core body temperature regulation, among others.

Poor circadian rhythms may lead to:¹⁴

• Cardiovascular diseases, including stroke or atherosclerosis
• Digestive disorders including ulcers, GERD, and IBS
• Metabolism disorders including obesity, diabetes, and metabolic syndrome
• Mood disorders including depression and anxiety
• Cognitive and behavioral disorders including difficulty focusing, reduced motor skills, and poor memory
• A weakened immune system
• Fertility Problems
• Sleep disorders including sleep apnea and insomnia may become worse

Blue light exposure in the average human has increased significantly within the past few decades. The sun used to be our only source of blue light. Now, with a huge increase in fluorescent and LED lighting, many of our offices, homes, and stores are filled with blue light.

Computer, tablet, and cell phone screen exposure have also increased exponentially. Many of us use these devices long after the sun has set. This can decrease our melatonin production. Melatonin is a hormone released by the pineal gland. It helps control your sleep-wake cycle.

Research suggests that wearing blue light blocking glasses before bed can effectively treat melatonin suppression.⁸

Blue Light & Digital Eye Strain

Computer vision syndrome (CVS), or digital eye strain (DES), is a group of eye health and vision problems. They result from prolonged computer, cell phone, tablet, or e-reader use. 

Common symptoms include:

• Eyestrain (red, dry, or irritated eyes)
• Eye fatigue
• Blurry vision
• Headaches
• Dry eye
• Neck and shoulder pain

There are numerous causes of these symptoms, including

• Improper lighting
• Incorrect viewing distances or angles
• Bad posture
• Screen glare
• Uncorrected refractive errors or other eye conditions

Notice that blue light is NOT listed as a cause of digital eye strain.

At this time, only a few studies have attempted to measure the effect of blue-blocking filters on digital eye strain. However, the studies that have come out and the American Academy of Ophthalmology (AAO) suggest that there is no evidence that computer screen light is damaging to your eyes. In addition, blue light filters do not provide any relief for digital eye strain.

In fact, according to the AAO:

“It’s not necessary to spend money on special eyewear for computer use. Here’s why:

• Blue light from computers will not lead to eye disease. It is true that overexposure to blue light and UV light rays from the sun can raise the risk of eye disease, but the small amount of blue light coming from computer screens has never been shown to cause any harm to our eyes.
• Sleep can be improved without special eyeglasses. You don’t need to spend extra money on blue light glasses to improve sleep— simply decrease evening screen time and set devices to night mode.
• Digital eye strain is not caused by blue light. The symptoms of digital eye strain are linked to how we use our digital devices, not the blue light coming out of them.”

— American Academy of Ophthalmology 

If you’re looking to help improve your symptoms of computer vision syndrome or digital eye strain, blue light blocking glasses are NOT recommended. However, DES affects many people, especially those who work online. Here are some tips to help minimize symptoms of DES.

How to Reduce Digital Eye Strain

Digital eye strain is not caused by blue light. It is caused by the ways we use our digital devices. Here are some methods you can use to combat digital eye strain:

• Maintain proper distance. Your computer screen should be an arm’s length away — approximately 25 inches, or at the point where your palm rests flat against the screen. The monitor should be positioned at a slight downward angle (about 15-20 degrees from your eye level to the center of the screen).
• Sit properly. Maintain good posture with your feet flat on the floor and back straight. Your chair should have a backrest. Relax your shoulders and keep your forearms flat with your wrists on the keyboard.
• Place reference materials properly. If you’re using reference materials, such as textbooks, a notebook, or a second monitor, they should be at the same height as your monitor.
• Blink often. One of the biggest causes of digital eye strain is not blinking. Our blink rate can reduce up to 50 percent when focusing on digital screens. Try to blink as often as possible to reduce dry eye and other symptoms.
• Reduce glare. You can adjust your screen settings, buy anti-glare coatings, or make sure your computer screen is high quality. This will reduce the amount of light reflected from your screen.
• Reduce competing lighting. Using drapes or blinds on windows and low-wattage bulbs in your work area can help reduce glare and contrast. Avoid using screens in situations of extreme brightness or darkness.
• 20-20-20 rule. Every 20 minutes, look at an object 20 feet away for 20 seconds. You should also rest your eyes for 15 minutes after every 2 hours of computer use. This helps prevent eye fatigue.
• Increase text size. Reading small letters can strain your eyes and cause headaches. Increasing your font size can help combat this.
• Clean your screen. Removing dust and smudges can help reduce glare.

If you are experiencing any digital eye strain symptoms, we suggest speaking with your local ophthalmologist or eye health specialist. They can check your eyes for undiagnosed vision problems, recommend best practices, and suggest any products that may help improve your condition.

Takeaway

Here’s what science says about blue light blocking glasses in regards to your eye and overall health:

• Blue light blocking glasses are effective at reducing melatonin suppression
• Blue light glasses may have the potential to help regulate your body’s circadian rhythm
• Digital eye strain is most likely NOT caused by blue light
• Blue light glasses have little to no effect on digital eye strain symptoms
• To reduce digital eye strain symptoms, see an ophthalmologist or optometrist and focus on how you interact with your devices rather than wearing blue light glasses
• More research is needed to fully understand the effects of blue light and whether blue light glasses have any medical value

If you’re interested in purchasing a pair of blue light glasses, read our review of the Best Blue Light Blocking Glasses