Light is one of the most common triggers for migraines and over 90 % of migraineurs are light-sensitive during the attack. Thus, many migraineurs seek dark room and rest during an attack. For example, stepping from indoor lightning out into the bright sunlight or getting bright sunlight exposure through an office window can start an attack within seconds and lead to excruciating pain for the rest of the day.
Migraine basic: it’s disabling, costly and poorly understood
Migraine is a neurodevelopmental disease. (S)
In migraines, the person experiences frequent headaches. Sometimes the headache pain is preceded by aura symptoms (i.e. visual disturbance, loss of words, and shaking hands) and other symptoms such as nausea, food cravings, muscle stiffness, and sensitivity to light (photophobia).
Migraineurs are hypersensitive (S)
Migraine is linked to “sensitive brain” (i.e. hyperreactivity of the brain and nervous system) and can co-occur with sensory processing sensitivity. In other words, migraineurs are sensitive to detect environmental signals such as sounds, light, and changes in temperature as well as food, bodily signals, and pain sensation. Light is one of the major causes of migraine and an extremely important one since it is present in many forms of our daily lives.
Migraine is disabling and costly. (S)
Migraine is the most disabling neurological disease in the world and one of the most disabling diseases from all diseases. 15 % of people globally suffer from migraine; Women three times as often as men. More than 90 % of people are unable to work and function normally during the attack, which might last for days. That means several days in pain, with lost social connections and lost working days. Considering all this, it is not a surprise that depression and anxiety are more common in migraineurs than non-migraineurs. In a family with a migraine-sufferer, the healthcare costs are 70 % higher. It has been estimated that healthcare & absenteeism caused by migraine cost 5-7 billion each year in the UK and 36 billion in the U.S.
Migraine is poorly understood, undiagnosed and untreated. (S)
In the U.S. there are 39 million headache sufferers but only 500 specialists. It has been estimated that over half of the migraine sufferers are never diagnosed because the majority of migraine sufferers never seek medical help. Migraine research is very poorly funded despite its economic impact on society and its importance in human health.
How light, migraine and eye pain are connected
Migraineurs have a so-called hypersensitive brain which is also common in photophobia (i.e. light sensitivity) (S) (S) As much as 30-80 % of migraineurs report light as a trigger for headaches. (S) Light can trigger migraine within seconds; for example when stepping from indoor lightning into the bright sunlight. This happens because of the general sensitivity of the brain and the so-called defect in habituation. A defect in habituation means that the brain will not adapt to the bright light like the brain of a non-migraineur does.
Light over-activates the nervous system of a migraineur
When you step out into the sunlight, your eyes will adapt to the new very bright environment. However, the brain of a migraineur will not adapt, but instead, the light signals will keep stimulating the brain more and more. This way, the person actually becomes increasingly sensitive. (S) In other words, the light and hypersensitive brain create a feedback loop which becomes a vicious cycle. This continues until a trigger point of migraine is reached. After the migraine is online, the brain is even more sensitive to all stimuli and this is normally when a migraineur seeks dark room, silence and rest.
Photophobia is reported in almost all migraine types and up to 90 % of the attacks. Photophobia is also one of the major diagnostic criteria for migraine. (S)
Even a cloudy day can be too bright for a migraineur
Migraineurs should be mindful of the fact that even between attacks (when a migraine is not online), migraineurs are more sensitive to light. Those without migraine reports light becoming too bright at 23,000 lux, which is the brightness of a sunny, cloudless day. However, for migraineurs, even illumination as low as 500-1000 lux can cause headache and pain; this resembles the illumination of a cloudy day. (S) (S) Thus, having a more sensitive brain, migraineurs may perceive things brighter that non-migraineur even in the same environment. Also, they may judge the bright light to be painful (a symptom of photophobia) whereas non-migraineur don’t. Thus, a normal sunny day or office lightning may trigger a migraine.
Common light levels outside (in lux)
- Sunlight: 100 000
- Outdoor light during a sunny, cloudless day: 10 000 – 25 000
- Outdoor light during a cloudy day: 100 – 1000
- Outdoor light during a very dark day: 10 – 100
Common light levels in offices (in lux)
- Normal office: 200-500
- Groceries, Library: 500
- Detailed mechanical work: 700-1000
- Office in which very detailed visual performance is required 1000 <
Bright office lightning can also trigger a migraine
The level reported to cause pain for migraineurs (500-1000 lux) is recommended for some working and public places, especially in those where the work requires fine detail (such as factories, production lines, hospital examination, and treatment rooms, libraries, groceries, supermarkets, and some offices). This sort of light exposure for several hours a day may explain some of the chronic headaches that migraineur with photophobia may feel.
Flickering and rapidly changing light can trigger migraine (S)
One of the most reliable triggers of migraines is flashing or flickering lights. For some, they provoke migraines more than office lighting or bright light. Just the sirens of a passing police car on an ambulance or a broken overhead fluorescent light at work or in the street might trigger a painful attack. There are many situations in which you may suddenly experience flashing lights such as flash photography, concert lights, decoration lights on in movies. Flickering is sometimes harder to notice; for example, some computer screens flicker and may trigger a migraine. (S)
Also, when the migraine is online, flashing lights can increase the pain intensity even if it didn’t trigger the attack. People with migraines generally have a lower tolerance for even low-contrast flicker.
Blue light increases migraine pain, green light reliefs (S)
Another aspect of light beside is brightness is the color of the light (wavelengths). A Harvard study found that certain wavelengths of light can increase the pain whereas others can alleviate it. (S) Interestingly, it was found that that particularly short and long visible light waves increased the pain intensity. These included blue (400-500) and red (600 and up) spectrum lights. However, this narrow band of medium frequencies (green light; 500-600 nm), which falls between blue and red light reduced headache pain even for 20 %. Another study found that blue light hurts more even blind migraineurs. (S)
Many everyday devices such as office lighting, street lighting, phones, laptops, and SAD-lights emit blue light. Blue light supports normal melatonin production when the exposure happens in the early hours of the day. However, it is harmful to human health (also for non-migraineurs) in the afternoon and evening time. Blue light suppresses the melatonin production even for 3 hours which means that if you look at the phone or computer sleep anywhere 3 hours prior to sleep time, your sleep might be delayed for 3 hours. Red light, interestingly, has been shown to increase melatonin production and has various health benefits for energy production and recovery. However, even red light can increase the pain of a migraineur when the migraine is online.
In one animal study, it was noticed that neurons in the thalamus, which relays light signals from the eye to the cortex, were the most responsive to blue light and least responsive to green light, explaining why the migraine brain responds favorably to green light and less favorably to blue. (S)
How to optimize the light to reduce migraines
The brain of the migraineur is hypersensitive and can’t adapt to environmental signals with the same efficiency as the brain of a non-migraineur. (S) For example, in bright light conditions, both the eye and the brain of a non-migraineur quickly adapt to the new illumination. This may not happen to migraineurs; instead, the eye, brain and nervous system keep reacting intensively which causes even more hypersensitivity until migraine is triggered. This is why good light hygiene is especially important for a migraineur.
1. Get a good pair of sunglasses and remember to use them
Get a pair of sunglasses with good anti-glare lenses, UV-protection, and polarized lenses. Some studies show that lenses with purplish-pink shade (FL-41) can reduce light sensitivity and headache frequency for migraineurs. (S)(S) Also, there are glasses with smart LCD lenses. Their tint will adjust according to the environment or let the user themselves to adjust the tin of the lens.
Remember to put the sunglasses on before you step out to the sunshine since bright light can trigger migraines in seconds for light-sensitive people. Also, street lights can cause strain and trigger a migraine because they are high in illumination and flicker.
Very light sensitive people might benefit from keeping the glasses on in very bright indoor lighting (especially in the environments where there are fluorescent LED lights over 500 lux) such as supermarkets, airports, hospitals, factories, and libraries.
2. Optimize your home lighting and office lighting
Migraineurs are especially sensitive for bright, flickering, blue-shaded led lights. (S) Sometimes too bright lights at home and office can cause headaches. They can also prevent or delay sleep since blue light exposure in the night suppresses the melatonin (sleep hormone) production.
Incandescent lights are traditional light bulbs that have a warm glow and don’t flicker. However, they are not the most ecological solution and they might be hard to find.
Warm white led lights: Led lights are easier to find, cheaper and long-lasting and some migraineurs tolerate Led lightning. However, they also emit low levels of blue-green light and some led lights might have invisible flicker.
Avoid cool fluorescent led lights: when possible, especially very bright (over 500 lux) once, since they emit high levels of blue light. They also flicker. These are typical in offices, shops, and street lighting. If you have a chance, change office and home lightning for non-flickering lights.
Smart home lighting allows you to control the dimness of your light, which is a useful solution especially when the attack is on. Migraineurs often find dim lights more tolerable and more calming. This is a more costly option but might make a significant impact on life when migraines are decreased.
3. Use blue light blocking glasses especially in the night
Blue light is can be especially straining for the eyes, which can cause tension in the trigeminal nerve and cause a migraine attack. It has also been shown that blue light waves can increase pain intensity during an attack. (S)
Wearing yellow-tinted computer glasses or blue light blocking glasses may help to reduce strain in the eye and tension associated headaches. It also protects melatonin production and sleeps which is very important for people suffering from headaches.
4. Reduce computer screen flickering
Even flickering computer screens have been shown to trigger migraines for light-sensitive people. To reduce computer screen flickering: 1. use good cables to connect the screen to the computer, 2. use a high-quality monitor, 3. make sure that the refresh rate of the computer screen is set high enough.
4. Get exposed to green light (or darkness) when a migraine is online
Blue and red light have been associated with increases in pain intensity during a migraine and green light decreased pain intensity (even by 20 %). Thus, blocking blue and red spectrum light and being exposed to green colored light might offer some relief for migraineurs especially during the attack.
5. Smart goggles
Though this product is yet not in the market, I want to bring up a product that I recently had a chance to test. They are a new patented smart eyewear technology that can help light sensitive migraineurs to manage migraine in all lighting conditions. INOPTEC is a German company that has invented smart goggles which:
1. Let the user set the illumination level (with an App) that they want their eyes to be exposed (no matter what is the environmental condition); for example 400 lux
2. The glasses lens tint change automatically in milliseconds in response to the change in environmental light so that your eyes will always perceive the same illumination
3. The glasses even out all the flickering so that flickering street lights and such won’t cause strain to the eyes
These glasses thus tackle both the problems (with brightness and with flickering) that most commonly trigger a migraine. However, this is not a product yet in the market, but when it will be this might potentially increase the life-quality of a migraineur dramatically.
Light optimization is crucial for light-sensitive migraineurs.
There are many potential light related triggers that may stay unnoticed; computer screens, office or street lighting or bright lights at home. In addition, some migraineurs can get a migraine from an outdoor light that is brighter than a cloudy day. If you pay close attention to environmental light and its associations to migraine attacks, you may start noticing that either (1) too bright light or (2) flashing or flickering lights is triggering a migraine for you.
The best way to correct lightning in order to support your health is to (1) optimize environmental brightness with sunglasses and correct indoor lighting, (2) trying to avoid flickering and flashing lights, (3) avoiding blue and red lights when the migraine is online.
I hope these tips have helped you in gaining more insights into migraines and light and offered you practical ways to reduce migraines with optimizing light.
If you are keen to read more about migraine relieves, you can find more (non-light related) migraine tips here: 10 ways to ease migraine with natural tools
Are you light-sensitive? What is your best tool to prevent headaches caused by light? Let me know in the comments!
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