Can Blue Light Cause Headaches?

Digital eye strain (DES) describes a cluster of symptoms related to the use of digital devices for a long period. Symptoms include:

• headache
• dry eyes
• sore or tired eyes
• blurry vision
• neck pain
• shoulder pain
• sensitivity to light

Computer screens, laptops, tablets, and cell phones can all cause digital eye strain. Each of those devices also emits blue light. This connection has led some researchers to wonder whether it’s the blue light that causes digital eye strain.

So far, there isn’t much research to indicate that it’s the color of the light that leads to DES symptoms. Researchers think the culprit is long hours of demanding up-close work, rather than the color of the light coming from the screens.

Photophobia, an extreme sensitivity to light, affects around 80 percent of people who have migraine attacks. The light sensitivity can be so intense that people can only get relief by retreating to dark rooms.

Researchers have found that blue, white, red, and amber light worsen migraine pain. They also increase throbbing and muscle tension. In a 2016 study involving 69 people with active migraine headaches, only green light didn’t intensify the headache. For some people, green light actually improved their symptoms.

In this study, blue light activated more neurons (the cells that receive sensory information and send it to your brain) than other colors, leading researchers to call blue light the “most photophobic” type of light. The brighter the blue, red, amber, and white light, the more intense the headache became.

It’s important to note that while blue light may make a migraine worse, that’s not the same as causing the migraine. Recent research shows that it might not be the light itself that triggers a migraine. Instead, it’s the way the brain processes the light. People who are prone to migraines may have nerve pathways and light receptors in their eyes that are particularly sensitive to light.

Researchers have suggested blocking all wavelengths of light except green light during a migraine, and some have reported that their sensitivity to light went away when they wore blue light-blocking eyeglasses.

Blue light has been implicated in several health conditions, including:

Sleep disruption

A 2018 study pointed out that sleep disturbance and headaches go hand-in-hand. Sleep problems can lead to tension and migraine headaches, and headaches can cause you to lose sleep.

Decreased leptin

Leptin is a hormone that tells your body you have enough energy after a meal. When leptin levels drop, your metabolism can change in ways that make it more likely that you will gain weight. A 2019 study found lower leptin levels after people used a blue-light emitting iPad at night.

Skin damage

Exposure to UVA and UVB rays (which are not visible) damages your skin and increases your risk of skin cancer. There is some evidence that exposure to blue light may also damage your skin. A 2015 study showed that exposure to blue light decreased antioxidants and increased the number of free radicals on the skin.

Free radicals can damage DNA and lead to the formation of cancer cells. Antioxidants can keep free radicals from harming you. It’s important to note that the dose of blue light researchers used was the equivalent of sunbathing for an hour at noon in southern Europe. More research needs to be done to understand how much blue light from LED devices is safe for your skin.

If you have been using a device that emits blue light, you may notice these symptoms:

• squinting
• burning, stinging, sore, or itchy eyes
• blurry vision
• tension in facial, neck, and shoulder muscles
• increased sensitivity to light
• headache

A few simple habits may help you prevent headaches while you’re using blue-light emitting devices. Here are some tips:

Adjust your workstation to help you maintain better posture

If you spend long hours in front of a computer without paying attention to the position of your body, you may be more likely to develop headaches. The National Institutes of Health recommend that you:

• Adjust the backrest on your chair or use a lumbar support pillow to make sure your lower back stays at a 90 degree angle to your hips.
• Raise or lower your armrests so your shoulders can relax as you type.
• Locate your keyboard an inch or two above your thighs.
• Keep your monitor 20 to 26 inches from your body.
• Place your monitor screen at eye level to avoid tilting your neck too much.
• Use a screen to reduce the glare from your devices.

Use a document holder

If you’re typing while referring to a document, prop the paper on an easel holder. When the paper is closer to eye level, it reduces the number of up-down movements for your head and neck, and it keeps your eyes from having to change focus dramatically each time you glance at the page.

Take breaks to stretch and exercise

Muscle tension causes most headaches. To relieve some of that tension, you can do “deskercise” stretches to loosen the muscles in your head, neck, arms, and upper back. You can set a timer on your phone to remind yourself to stop, take a break, and stretch your body before you get back to work.

Try the 20/20/20 method

If you use an LED device for hours at a time, you can reduce the risk of DES with this simple strategy. Stop every 20 minutes, focus on an object around 20 feet in the distance, and study it for about 20 seconds. The change in the distance gives your eyes a rest from up-close and intense focusing.

Change the light settings on your device

Many devices allow you to switch from blue light to warmer tones at night. There is some evidence that switching to warmer tones or “Night Shift” mode on a tablet can help maintain your body’s ability to secrete melatonin, a hormone that prepares your body to sleep.

Keep your eyes moist

When you’re staring at a screen or concentrating on a difficult task, you are probably blinking less than you normally would. Using eye drops, artificial tears, and office humidifiers may help you maintain moisture levels in your eyes if you’re blinking less.

Dry eyes contribute to eye strain—and they’re also related to migraine headaches. A large 2019 study found that the odds of having dry eye disease were about 1.4 times higher for people with migraines.

Search for “blue-light glasses” on the internet, and you’ll see dozens of specs that claim to prevent digital eye strain and other dangers. While studies have shown that blue-light glasses are effective at blocking blue light waves, there isn’t a lot of evidence showing that these glasses prevent digital eye strain or headaches.

Some people have reported headaches from blue-light blocking glasses, but there haven’t been any reliable studies to support or explain these reports.

It is not uncommon to have headaches when you first wear new glasses or your prescription has changed. If you’re having headaches when you wear glasses, wait a few days to see if your eyes adjust and your headaches go away. If they don’t, speak with an optician or ophthalmologist about your symptoms.

Working and playing for long periods on blue light-emitting devices like phones, laptops, and tablets can lead to headaches—but it may not be the light itself that causes problems. It may be posture, muscle tension, light sensitivity, or eye strain.

Blue light does appear to worsen the pain, throbbing, and tension of migraine headaches. Using green light, on the other hand, may lessen migraine pain.

To prevent headaches while you’re using a blue light-emitting device, keep your eyes moist, take frequent breaks to stretch your body, use the 20/20/20 method to give your eyes a rest, and make sure your work or play area is set up to promote healthy posture.

Researchers don’t yet know exactly how blue light affects your eyes and your overall health, so it’s a good idea to get regular eye check-ups and speak with a doctor if headaches are interfering with your quality of life.