Jan 04 2008
Global Warming Is Causing More Migraines
OK, not directly. This is more of a manifestation of the law of unintended consequences. Here is the chain of events:
Concerns over man-made global warming have increased awareness of the need for energy conservation. This in turn has led to the popularity of compact fluorescent bulbs (CFB’s) as replacement for the old incandescent bulbs. (CFB’s use 75% less energy for the same light output, as they generate less waste heat). Governments, wanting to seem proactive in tackling the high-profile problem of global warming, are beginning to pass laws requiring the phasing out of incandescent bulbs in favor of the new fangled CFB’s. This will save money, energy, and atmospheric carbon. So far so good.
However, 38.1% of migraine headache suffers are sensitive to bright or fluorescent lights, which can trigger migraine attacks. Fluoresecent bulbs have a subtle flicker – which is too fast for most people to perceive, but it’s there. (BTW – computer screens also flicker too fast for most people to see, but some people can perceive the flicker of computer screens and this can cause headaches and eye strain.) For some migraine sufferers, any bright light can trigger a migraine, but for most light-sensitive migraineurs a flickering light is much more of a hazard. For example, the light dappling through the trees while driving along a country road creates a flicker effect that can trigger a migraine.
So those migraine sufferers who are light sensitive now face a world illuminated by flickering fluorescent bulbs all thanks to Al Gore and global warming. This has led some migraine advocacy groups to lobby their respective governments not to ban incandescent bulbs outright. Perhaps a special exception can be made for those with migraines. Before long I may be writing a prescription for a migraine patient to obtain otherwise-banned incandescent bulbs for their home. (disp: 12 70w incandescent bulbs, use as needed for domestic illumination, refills: 5)
The question of how migraine attacks are triggered by bright or flickering lights is an interesting one. The current thinking is that migraines are very similar, neurophysiologically, to seizures. Both are the result of excessive or out-of-control neuronal firing in the brain. Seizures can be triggered by many of the things that trigger migraines, including flickering lights (remember the Japanese video game that induced seizures? – although this sparked a flurry of anxiety attacks that were not true seizures also). Many of the same medications that are used to treat seizures are also effective as a preventive treatment for migraines. All of this speaks to a similar underlying mechanism.
The current working model of migraines is that they begin with activation of the trigeminovascular reflex – the trigeminal nucleus is that part of the brainstem that receives sensory information from the face. This sensory information is connected to the cranial vasculature. Hyperactivity in the trigeminovascular system results in a phenomenon known as central sensitization, where the trigeminal nucleus becomes over responsive to sensory input. It also causes the cranial vasculature to go through a process of vasoconstriction (shrinking of the blood vessels) followed by vasodilation (expansion of the blood vessels).
All of this relates well to the symptoms of migraines. They typically begin with an aura, which is commonly visual involving a bright zig-zagging distortion in the vision which moves across the visual field, followed by a trail of darkening of vision. Other auras are possible also, including numbness, tingling, weakness, or nausea. This is followed by a pounding headache (caused by the vasodilation), which is classically one-sided but can occur in any distribution. There are also symptoms of hypersensitivity to sensory input – including intolerance of light and loud noise and sometimes increased sensitivity to even soft touch over part of the face. These symptoms then slowly subside. A typical migraine will run through its course over several hours.
Migraines can be very debilitating and significantly impair quality of life, so having an increased frequency of migraine due to widespread use of CFB’s is no joke. One of the primary preventive treatments for migraines is avoidance of triggers.
And therein lies the dilemma. I am all for energy conservation, especially through implementing new technologies that are more efficient and cost effective. That’s a win-win. It is just unfortunate that there is this unintended consequence of potentially making life more difficult for those who already have the burden of suffering from migraines. At the very least governments need to take this into consideration and perhaps not be so heavy-handed in banning incandescent bulbs.
But fear not – technological advancement has already provided the ultimate solution to this dilemma: the LED lightbulb. These are already available and are cost effective. LED bulbs are 30 times as energy efficient as incandescent light bulbs and last 60 times as long. They do not contain mercury as do CFB’s, and they produce a more natural white light without any migraine inducing flicker. The only downside is the upfront cost is much higher, even though the long term savings are huge. And LED lights will only get better over time.
Ironically, just as there is a big push for CFB’s they are already obsolete. In fact, the technology should be entirely bypassed in favor of even more efficient, environmentally friendly, and non-migraine inducing LED’s.
![[del.icio.us]](http://images.del.icio.us/static/img/delicious.small.gif){kind=small}
Print This Post
23 Responses to “Global Warming Is Causing More Migraines”
Here in the UK we run on 220V household current and two of my lighting fixtures regularly kill any CFB put in them; I suspect voltage spikes.
Anyway, LEDs do not seem to suffer that fate and are smaller. At this point, LED bubls are not much more expensive than CFBs but the ones I have are very directional. The extra lifespan is the real selling point for me.
I’m also impressed that Dr Steve seems to have posted this before 7AM. Does he ever sleep?
ellazimm – Wordpress allows you to forward time stamp your entries. I typically will write an entry the day before or in the evening and then have is post automatically first thing in the morning.
I prefer to think that, like me, you wake up in the middle of the night, can’t get back to sleep and, rather than waste time, sit at your computer and do something. It usually works for me.
Has anyone factored in the extra cost to the environment of manufacturing and disposing of LCDs or CFBs? To measure the real “green-ness” of something its whole life must be accounted for.
It is true that Steve never sleeps, like Thai Ngoc (http://www.thanhniennews.com/features/?catid=10&newsid=12673). Steve is also a breatharian.
Great post Steve. I caught Dr. Gupta on CNN mentioning this today and had initially assumed that it was another anecdote=major health crisis report. I guess there may be some basis to this after all.
This is more a matter of manufacturing and distribution catching up with what we need since compact flourescents are on the shelf already. LEDs are pretty cheap wholesale but putting a bunch of them together with diffusion and whatnot seems to make them hugely expensive.
The problem with LEDs relates to what they are made of. Red LEDs are cheap and easy to make. To get white light you need photons on the blue end of the spectrum. Those are higher energy and so need a higher band-gap material to make them. Those materials are a lot more expensive and difficult to work with.
The problem of flicker can be addressed using different phosphors. CFBs use mercury vapor to generate UV light of 252 nM, then 3 different phosphors convert those photons into photons that maximally stimulate the light receptors of the eye. The “white light” of fluorescent lights are actually just the right balance of 3 different colors that appears to be white.
The flicker comes from using AC to power the electrical discharge through the mercury plasma. Light only comes out during part of the discharge. CFBs can use higher frequency to reduce or the flicker by increasing the frequency.
If you use a phosphor that has some delay in when the fluorescent photon is emitted, the flicker can be eliminated. I think those phosphors cost more, or more of them is required, or the efficiency is lower.
Unlike traditional magnetic ballast fluorescent lights the new electronic ballast CFL’s do not have a 120 Hz continuous flicker, although some may flicker a few seconds on start up. Some claim that it is the spectral properties that cause migraines, but I could not find in a brief search a good authoritative source to confirm this. One company has announced plans for a lower cost (
Mostly on subject, since you brought it up: Migraines.
I’ve heard conflicting info regarding these. I personally experience the very symptoms you describe in the article above, but my personal physician says that what I have are “cluster headaches,” not true migraines. Yet, at the same time, I participated as a subject in a research piece studying artists and the effects of migraine on their work. Most of the stuff in the initial questionnaire pointed out that I indeed (less frequently now) suffer from a form of migraine w/aura.
Is this really such a subjective diagnosis? And is it true that it’s mostly women that suffer from the majority of true migraine? I’ve never gotten what I consider a definitive diagnosis one way or the other. I’ve never taken or really needed medication for my episodes, as they were (though very intense) brief, lasting less than an hour in most instances.
Just curious, again, since you brought it up. Any further info would appreciated.
Just a small correction to yet another excellent blog entry:
Only CRT computer screens flicker, the more popular LCD screens do not flicker. With CRTs, the image is constantly being drawn on the screen (somewhere between 60 and 120 times a second, this is the refresh rate). LCDs on the other hand, have a bulb or some other light source that stays lit, and the liquid crystal that the light passes through constantly shifts.
The flicker is actually a positive for home theatre enthusiasts since there is no motion blur thanks to the flicker. LCD manufacturers are trying all sorts of tricks to reduce motion blur.
http://hometheatermag.com/gearworks/707gear/
Cluster headaches are a migraine variant. Their primary feature is that they cluster – they occur daily, usually at the same time of day, for weeks, then will subside for weeks or months.
Cluster headaches also tend to be briefer than migraines, and more severe.
Migraines are more common in women, cluster more common in men.
Both are diagnosed by clinical history.
Minor correction: I think the situation that I think you are referring to which caused seizures in Japan involved the television Pokemon (which is based on a video game).
http://en.wikipedia.org/wiki/Denn%C5%8D_Senshi_Porygon
http://faculty.washington.edu/chudler/pokemon.html
I use a 3-Way CFB bulb in my living room. It has quite a noticeable flicker, I don’t think the technology to make a 3-Way bulb is where it should be. I usually can’t leave it on very long, certainly can’t read with it. Also, at the lower setting I think it is emitting in the infra-red because it actually blocks my TV remote!
Does the article break down what part of the 38% are due to bright lights, not fluorescents specifically? Does the article state what type of florescent bulbs are being tested? My understanding is that electronic ballast bulbs do not flicker in any perceptible sense because the cycle rate is 20,000+ times per second, vs only 60 times per second for electro-magnetic ballasts. All of the compact/spiral bulbs I’ve seen use electronic ballasts, and most decent quality overhead tube-type fluorescent bulbs do now as well. Of course millions of people are trapped in aging offices and schools that have old magnetic ballast lights, but those are also annoying for other reasons, such the the buzzing noises they make, and their relatively poor efficiency. New florescent bulbs can also be purchased in color temperatures from pure white, to incandescent yellow, to cool blue, so that is no longer a real strike against them.
LEDs are fine for accent and directional/signal lighting, which is why you see them in car brake/tail lights and stoplights, but you never see them in headlights (because they can not flood an area with bright light). Many of the brighter residential LED bubs also require large heat sinks. Hopefully this situation will improve soon.
And I agree with the other poster who mentioned the most common monitors (LCDs) for sale now do not really flicker. They often use fluorescent backlighting (and sometimes LEDs in high-end models), but the ballast in the LCD case would always be electronic.
I suspect good quality fluorescent fixtures won’t actually cause any migrane problems, but I’d like to see the full text of the paper. Maybe, in addition to nudging away from incandescents, governments should also provide incentive to replace older electro-magnetic ballasts, so nobody continues to suffer migraines due to indoor lighting. That said, I don’t want to see the whole fluorescent technology looked down upon because of the downsides of the technology as it existed in the early 70s — newer manufacturing methods are far superior.
Uh oh, CFBs contain mercury and therefore are probably contributing to the rise in autism! Let the panic begin.
http://news.bbc.co.uk/1/hi/uk/7172662.stm
The study which underpins this post (that 38.1% of migraines are caused by light) – appears to be a ’survey’ where patients are asked to attribute the causes of their migraines themselves…
This seriously undermines your point – in effect you are using the same level of evidence as the kind of ‘consumer satisfaction surveys’ employed by homeopathic ‘hospitals.
The article doesn’t even mention ‘flourescent’ light – just ‘light’…
‘weather’ and ‘not eating’ are greater factors… – – what conclusions do you draw from that…??
Dean,
I did not mean to imply that the conclusion that migraines can be triggered (a better term than “caused”) by bright lights is dependent upon this one study. This is a very well established feature of migraines, and is part of the diagnostic criteria. I referenced this study just to indicate the probable percentage of migraine sufferers who report that their headaches can be triggered by bright light.
Basing such conclusions on the subjective experience of the patients and survey-type questioning is problematic, but is not the same as “satisfaction surveys.” Subjects are not asked to make a judgment, just report the presence or absence of a symptom. There is still a subjective component, but it is not the same thing. Also, a a recent study shows that if anything surveys underestimate the number of patients with light-sensitivity. (http://www.ncbi.nlm.nih.gov/pubmed/17868350?ordinalpos=8&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum)
Other studies, and common clinical practice, use headache diaries – patients record the incidence of migraines, listing symptoms and possible triggers. This is more quantitative than surveys.
As a clinical neurologist I take very careful migraine histories, with detailed questioning, not just generic survey questions. And the 38.1% figure for photophobia is much lower than in my patient population. I figured this was likely due to the fact that I see a more severe mix of patients. Patients who have photophobia commonly report that fluorescent lights especially will trigger their migraines.
Steven,
- you haven’t offered any evidence for your hypothesis than this :
“Patients who have photophobia commonly report that fluorescent lights especially will trigger their migraines.”
- and the statement at the top of this post:
“However, 38.1% of migraine headache suffers are sensitive to bright or fluorescent lights, which can trigger migraine attacks.”
- is simply factually incorrect – the abstract makes no mention of ‘flourescent lights’ – let alone the new bulbs.
It would seem that the new energy-efficient bulbs are no brighter than incandescent bulbs – and they don’t actually flicker.
Before you start writing prescriptions for light bulbs, perhaps you should examine the evidence a little more critically, and employ a little scepticism? Have you considered there is a psychological element to triggers?? – since ’stress’ is the most effective trigger of all, there would seem to be rather strong evidence for this from the same study? If patients learn to associate new light bulbs (or any other random stimulus) with migraine – Pavlovian conditioning will lead to a rise in stress levels which itself should be enough to trigger an attack…??
You may not be doing your patients any favours by encouraging such a belief – and may be limiting them to an existence where they can only live where they believe the lightbulbs are ’safe’…
Steven – one other issue which was brought up over at Bad Science was the possibility that the rate of flicker of a normally working CFB is much higher than can be percieved by people. It would certainly be much more rapid than sunlight shining through leaves while driving.
Anyway, it would be great if you could comment.
The flickering issue of the Fluroescent bulb is nothing new, and has been an addressable issue since the bulbs where first invented. A single bulb would cause a some what strobascopic effect and so was not to be used in lighting rotating machinery, Lathes, mills etc. because of this. The use of twin fixture bulbs,( 2 bulbs in the same fixture) was introduced to cancel this effect . Is the technology in the new CFB’s that much different than the existing old style straight bulbs, or is this a few people whining because they are being told they have to change? As far as the mercury is concerned, isn’t it also present in the straight bulbs? I for one have really been amazed that the mercury issue has been so overblown. The mercury thermometer was used for almost a hundred years, and we have mercury in the dental fillings in our teeth. As a child, and teenager we played with mercury in our hands, and were amazed by the shiny liquid metal, as a person now approaching the late years 50+ I am healthy and have suffered no ill effects. So where/what is the danger. I do believe that mercury salts may have some hazardous properties, but so does rat poison, so can somebody out there with the proper credentials please help starighten out all of us by providing the truth!!!
My wife has suffered from Migraines for years. We have experimented significantly with this and come to specific conclusions as to the causes, most of which are related to flashing lights. Her are our findings, for her.
0. Strobe lights such as at a dance or theatrical event, 100% of the time cause a migraine.
1. Sun through the trees in a car, definitely 100% of the time causes her a migraine. This is of course a very bright flash at a relatively slow rate. Sunglasses don’t help. She has to look away or avoid such travel.
2. Older ballast fluorescent overhead lights (buzzing kind) cause a migraine almost all the time for her. Certain places she has to go from time to time consistently cause migraines, they have those lights in places. So flashing lights at 60 cycles cause them.
3. CFB’s cause her migraines. I had one in my office, only room in the house with a CFB at the time. She got headaches when she used the computer. I changed refresh rates, then monitors, no luck, until I changed the bulbs in the room back to incandescent and the problems went away. She can tell right away when she goes into a CFB-lit room that there will be a problem (feels a “pull” on her eyes)
4. (most) LCD’s do flicker! They use CCFL — cold compact flourescent lights. If it’s true that they flash 20,000 times per second, then my wife’s brain can process that. I brought home a brand new 37″ LCD TV (fluorescent backlit) last week, it caused a headache, she could feel that “pull” the moment I turned it on, I packed it up and returned it within an hour of unpacking. The laptop LCD monitor (1920×1200 15″) causes a headache.
5. CRT monitors with refresh rates set up in the 100’s do not cause her migraines. I can only guess that it’s due to the phosphors being slow enough to be apparently steady. The Sony Trinitron CRT we had on a system before the laptop was fine for headaches.
6. CRT TV’s do not cause her migraines. I would imagine again it’s the slow phosphors. Our CRT’s are slowly dying and becoming obsolete as HD approaches., we will soon be forced into some sort of flat screen model. As metioned, the LCD experiment was a dismal failure. I’m hoping plasma is better, but our main viewing room is awash in sunlight.
I live in Canada. CFLs were just mandated here. Will I be forced so smuggle incandescent bulbs in from the US? Will I eventually get arrested for it?
If my wife stays in our house (all incandescent, all CRT televisions) and doesn’t use the LCD-equipped computer, avoids flashing sunlight during drives, and goes only sparingly to stores lit by fluorescent tubes, she can have a migraine-free existence.
We have talked to medical doctors and eye doctors. They either dismiss or disbelieve our story.
Finding this article confirms at least that others have this experience to some degree.
This is a debilitating thing to live with. Avoidance is rather infeasible. As LCD TV’s and CFB’s gain traction, it will surely become almost impossible.
Is there any hope of fixing this problem for her? Medication? Surgery? Therapy? So far we can’t get anyone to even acknowledge that it’s real, which is why I was so happy to find this article. Fixing it seems like a pipe dream…
@envrioguy: I’m not sure what a “typical” migraine sufferer’s symptoms are, but I can certainly empathize with what your wife must have to put up with. CRTs and CCF-backlit LCD monitors make my head pound and my eyes feel like shit. It’s taken a very long time (maybe too long) for me to figure out that staring into computer screens has been the “trigger” that causes me these symptoms. I always get the throbbing and the eye soreness, but they are only occasionally accompanied by intense headaches. Unfortunately, it’s hard for me to avoid computers (my background is engineering, but it’s a long story), so I just try to minimize the amount of time I spend on them and put up with the symptoms when I can’t. Recently, I decided to purchase an LED-backlit LCD monitor, and I should receive it by the end of the week; I’m curious what the results will be? Because I’ve never had problems with bright lights in general … though I can’t recall having any problems with fluorescent lighting either until I started spending a lot of time with computers. I’m also curious about plasma and OLEDs, though for now, neither of those seem to be practical alternatives (plasma for the “plasma burn” issues and the only OLED monitor on the market being 11″ and $2,000). Would you keep me posted on any new developments? If so, I’ll certainly be very happy to do the same.
I don’t get migraines but I sure do get excessively tired and exhausted. This is embarassing when it occurs at a college class or at church. And no, the speaker isn’t boring. Both places are immersed in florescent lighting. Sometimes it occurs at the local Walmart especially since they have the new “green” system.
I also get highway hypnosis. I wonder if that is also related in some way.
I thought it was strange and when I mentioned it to my brother, he said he has it, too.
Any solutions? Does magnetic therapy help?
Envrioguy, I have similar symptoms, but less severe. I can’t stand in front of LCD or plasma displays, after which I begin to feel migraines and difficulty in doing simple and logical reasoning. I found my problem when I bought a laptop, 5 years ago. Meanwhile I did some research.
I don’t like CFB, it makes more difficult to read and gives me some headaches, but it doesn’t give me migraines.
Both plasma and LCD displays trigger migraines. I found that unlike it is commonly believed, both LCD and plasma do flicker. Yes, that’s right, they do. Most people don’t feel the flicker because times it takes to refresh the display is much lower than in CRTs, however, it works like a flash.
Unlike Plasma, in an LCD panel, each transistor (TFT) cannot be polarized all the time under the same tension, so, typically, it is reversed every frame. However, transistors are not perfectly symmetrical; as a result, there is a flicker at half the refresh rate (25-30Hz). This effect appears almost unnoticeable to most people due to pixel interleaving. Another aspect that applies to plasma and most of the LCD panels, is the FRC (Frame rate Control), sometimes called temporal dithering, which is a technique to increase the number of levels of color. With FRC, some colors tend to introduce flickering at frequencies that range from 1/4 (15Hz) to 1/2 (30Hz) of the refresh rate.
I tried LCDs with LED backlights but the problems remained.
I believe that my problem is due to flicker only. However, until now I did not found any solution for it.
Steven, do you known any kind of medicine that might lower the flicker symptoms, or the sensitivity to these kind of “flash flicker”, so I could be able (even if with small headaches) work with LCDs for short periods?
Any help is highly appreciated.
Thanks.
John