Posted tagged ‘Fluorescent’

Colour tolerance and myopia

May 11, 2010

I’ve mentioned before that my partner really hates coloured light.  I haven’t tried that many colours on him, just the blue lightbox and a range of yellow and amber bulbs, but he has strongly disliked all of them.  My eye specialist has finally given a reason for why this might be the case. Colour, she says, is very important to myopes (short-sighted folks), and the more myopic you are, the more colour will matter to you.  I’m fairly fussy about colour myself, I can’t stand fluorescent light (though that’s probably a case of colour and flicker) and I’m very picky about colours when it comes to reading and tinted lenses, though I don’t know how far that is caused by having Meares-Irlen Syndrome.  I’d be curious to test my partner some time and see how much colour he can tolerate, if there are any colours he finds easier than others, or if he’s only really happy when the light is white or close to it.  I mentioned to the eye specialist that I find yellow and orange light mercifully comfortable, and she said, “Oh yes, yellow light is very soothing for the eyes.”  For reference, here is how myopia is usually categorised:

0 to -3: mild myopia
-3 to -6: moderate myopia
-6 to -10: severe myopia
over -10: extreme myopia (not usually listed as it’s so rare)

Including astigmatism, I’m about -7, so my eyesight’s worse than that of most people but I still know a fair few people who are at a similar level to me.  My partner, on the other hand, is about -19.  Before I met him, the worst myopia I’d encountered was one guy at -12 and a woman at -10.  Several opticians he’s been to have never seen myopia as bad as his, although it’s by no means the worst around.

So his reaction is unlikely to be the norm, and even my degree of fussiness about light colour seems fairly unusual.  To people who have tried different coloured light or lenses, are you myopic, and have you found difficulty in tolerating the colour?

What colour should I use for darkness therapy?

February 12, 2010

By now you may be feeling rather overwhelmed by all the colours I talk about for darkness therapy.  Between my own visual comfort and what is actually available, I use products in a variety of colours.  The one thing they all have in common is that they either block/filter out blue light, or they product light which does not have any blue in it.  This means you can use yellow, orange, amber, red, or brown.  You may find that you have strong preferences concerning colour to the point where the wrong one for you makes you feel unwell, particularly if you have dyslexia, migraine, ME/CFIDS, Meares-Irlen Syndrome, epilepsy, and possibly severe myopia (short-sightedness).  Make sure you can try out a colour before committing to anything expensive.


This is the lightest colour of the set.  When used to tint glasses, it increases contrast in a way some people can find disconcerting.  It’s often available as a standard tint for sunglasses, though be sure to ask your optician whether it blocks 100% of blue light.  I have seen some websites selling yellow lenses that claimed that they would work for darkness therapy, but this study suggests that they may not.

I’ve seen two shades of yellow used as a coating for incandescent light bulbs.  Most often it’s the slightly more orangey one.  The light is a little more orange than you’d expect from looking at the bulb coating, and may be described as a marigold yellow.  I personally find it very pleasant.

Reflector bulbs can be sold with a yellow coating, but unless you are going to be using tinted glasses as well, I don’t recommend these as the coating is only translucent and I think it permits some blue light to come through.

Fluorescent bulbs can be bought with a yellow coating as well.  I don’t know what they’re like as I’ve never tried one.  They’re often sold as “bug lights”.

Yellow is rarely used for LEDs, and on the two occasions when I bought something that was sold to me as containing yellow LEDs, they turned out to be a horrible orange.  I’ve been told by lighting specialists that yellow is a tricky colour for LEDs, which is why you don’t see it often.

Candle flames are mostly yellow, although these is a small amount of white light in there as well which may or may not be enough to influence your circadian rhythm.


This is the colour I chose for my tinted glasses, mainly because it’s directly opposite blue on the colour wheel and I already knew that I got on with it from using an orange monitor filter on my laptop.  Objects viewed through orange lenses appear golden yellow, for some reason.  I find it quite a pleasant colour for lenses, it doesn’t increase contrast, and as apparently is true for many people, it makes it easier for me to read.  The colour distortion may bother you, however.

Orange-coated incandescent lightbulbs are likely to be sold as “amber”, but the coating looks pinkish-orange to me.  The light is a fair bit darker than that produced by yellow-coated incandescent bulbs, being an orange that is almost closer to pink.

Orange-coated reflector bulbs are also usually sold as “amber”.  The coating is again translucent, but I think it probably cuts out most, if not all, blue light.  It’s not the best light source, though, I wouldn’t recommend it.

Orange LEDs are commonly used for appliances, such as on electrical sockets.  Again, there seems to be difficulty in getting a pleasant colour, although the light on my kettle is not bad.

If you wish to buy a salt lamp for decorative purposes, the thick layer of salt looks pink when it is not illuminated and glows orange when you put a bulb in it.  I suspect that a small amount of white light is still getting through mine, so I put in a pink-coated 15W bulb instead and it nows glows a deep salmon colour.

Amber and brown

Amber may be used to refer to orange, or it may be a shade of brown (orange + black).  Amber and brown are common colours for sunglasses, although it has been suggested that not all sunglasses which claim to block all blue light actually do so.  I have no idea whether this is true, I suspect that it may be a marketing myth, but again, check with your optician.

The main advantage of brown is that it doesn’t distort colour in the way that orange does, and the disadvantage is that in order for it to be strong enough to block blue light, it will be quite a bit darker than the equivalent orange.  I tried a pair of amber fitover blue-blocking glasses and not only did everything appear very dark through them, but they completely hid the parts of my face which were behind them.  My orange glasses do nothing of the sort.


Red is the darkest pure colour of the set, and anything viewed by red light or through a red filter will appear monochrome.  This will be off-putting for many people.  On the other hand, there’s a school of thought that red is far more effective than orange or yellow for darkness therapy, so you may prefer to use it for that reason.  However, this site claims that “red is a very uncomfortable color to look through”, so you may prefer to restrict its use to light bulbs.

Red-coated incandescent bulbs exist, but I have not tried them.  You can also buy incandescent bulbs with red (translucent) glass called “fireglow” which will give off more light than the solid-coated bulbs, but I don’t know if the translucent coating is enough to filter out blue light.  Red reflector bulbs are probably similar to these.

Red LEDs are cheap to produce and give off a pleasant colour, so they’re commonly seen in remote controls and so forth.  If you want to use a bike light as the equivalent of a torch, it will probably be red.

Red glass is a popular option for tealight holders.  While the jury is still out on whether candlelight is acceptable for darkness therapy, I would guess that putting the candle into a red candle holder should be enough to compensate for the small amount of white light that may be present.

Bright light therapy: review of the GoLite

February 12, 2010

The GoLite is a nifty little lightbox at only 15 x 15 x 3cm, which makes it extremely portable.  It comes with extra international plugs and a padded carry case, and I have successfully used mine in Israel as well as the UK.  My version is not rechargeable, but the newer ones are, so that if you need to use it somewhere else, you wouldn’t have to scrabble around on the floor to unplug and replug cables.  The case has a clamshell design, so that when it’s closed the lid protects the LED panel, and when it’s open the lid acts as a base.  Unfortunately, the stand is not adjustable and I’ve found that it’s at the wrong angle when it’s placed on a table, so that I have to prop it up on my glasses case.  LEDs are a very directional form of light and you have to position LED lightboxes just right.  While the brightness of traditional fluorescent lightboxes is measured in lux, with 10,000 lux being ideal, the light produced by LEDs is so different that the lux measurement doesn’t apply.  I don’t think I’ve heard yet of an LED lightbox which was not bright enough, but do read reviews if you are looking at different models.

Unlike the lightboxes which came before it, the GoLite doesn’t just use LEDs, it uses blue LEDs. The manufacturers found through research that there’s one particular bandwidth of light that affects the circadian clock, at around 470nm, and luckily blue LEDs naturally peak in exactly that bandwidth.  (Despite what the manufacturers claim, all blue LEDs do this, so any lightbox with blue LEDs should do the same job.)  Traditional fluorescent lightboxes do contain some light in that bandwidth, but they don’t have very much of it.  By isolating the correct bandwidth, the idea is that you can get away with a smaller lightbox and a shorter treatment time, thus hugely increasing how effective it is.  My experience and all the reviews I’ve read of blue lightboxes appear to bear this theory out.  The manufacturers recommend a treatment time of 15-45 minutes, which for bright lightboxes is excellent, and even with stubbon sleep disorders I have always found 35-45 minutes to be sufficient.  The snag is that not everyone likes blue light, but most people are fine with it and it’s a pretty soothing light as such things go.  I have difficulty tolerating bright light and I’m absolutely fine using the light on full intensity.  The build quality appears to be good and the only problem I’ve had in five years of near-daily use is that one of the 66 LEDs now only lights up intermittently, which does not affect the efficacy or visual comfort at all.

Apart from the inability to adjust the stand and the high price, my only niggle with the GoLite that I own is that the settings are a nuisance to understand and the instruction manual wasn’t much help.  It does have various features, including a clock, treatment timer, variable light intensity, and the ability to save three different programmes, but you may need to ring up your seller or the manufacturer in order to learn how to do this.  It’s not intuitive to set, involving strange combinations of holding down several buttons at once, and you’re unlikely to remember how to do it.  After five years of use, I’ve sorted out my preferred treatment time and light intensity so that I just need to turn it on and hit “light” in order to get my treatment running, but I have no idea how to change the programme settings or even how to change the time when the clocks go back.  Thankfully I only use the one programme and don’t use it as my clock (it lives in a bedside drawer when not in use), so this doesn’t particularly matter.  I did try using Programme B for a shorter treatment time with lower light intensity for when I had a headache, but eventually I stopped bothering.  If I have a migraine, I skip the lightbox for that day, and if it’s only a mild headache, the light doesn’t seem to do me any harm.

The GoLite was my first big step in improving my sleep.  Before using it, my daily pattern was 25 hours, so that I would fall asleep an hour later every day.  I started using the GoLite when I woke up, and the pattern immediately stabilised at 24 hours.  With judicious occasional use of sleeping tablets, I could even move my bedtime and waking time back when they had crept too far forward, although I still tended towards late hours and had to accept that while the Non-24 Sleep-Wake Disorder was now firmly under control, the Delayed Sleep Phase Syndrome was only partially managed.  (Darkness therapy is what finally solved the latter.)  After some experimentation, I have settled on a 45 minute treatment time, although now that I am using darkness therapy as well I may be able to get away with less.  I found after a few years that even if I skipped my treatment for the odd day here and there, my sleep pattern remained stabilised at 24 hours, so it seems that to some degree my circadian clock has been retrained.

I bought my GoLite in 2005, back when it was the only LED lightbox on the market and pretty new at that.  The version I bought was the P1 (the link takes you to the place I bought it from, which I highly recommend).  As you can see, it’s still for sale at quite a good price now, although some people may prefer to pay more for the newer, fancier versions.

Back then, the GoLite was made by an American company called Apollo Health who made a variety of fluorescent lightboxes as well and had done quite a lot of research into light therapy.  I loved their website.  It had some of the best information about bright light therapy for various conditions that I’d ever seen, and devoted plenty of space to sleep disorders, where most lightbox manufacturers just talk about SAD.  It even had a free test you could take to find out whether you had a circadian rhythm disorder, rather like the Morningness-Eveningness Questionnaire.  When I rang the company, there was an extraordinarily knowledgable chap I could speak to about exactly how I should treat my sleep disorders using light therapy.  Apollo Health has since been taken over by Philips, which means that you have a household name, you can speak to customer services in your own country, and it’s doubtless doing great things to get the product out there, but that wonderful resource of the Apollo Health website has been lost.

The new GoLite

Philips have redesigned the GoLite so that it now looks rather different.  I haven’t tried it out yet, but I’ve spoken about it in some depth to the National Light Hire Company.  It does look snazzier, but frankly I’m not that interested in its decorative value and it’s certainly not something I’d be willing to pay more money for.

The new GoLite BLU (no, Philips, misspelling words does not make your product more attractive to me) still lacks an adjustable stand, but it does feature a built-in battery, so that it is rechargeable.  I’ve always hated having to mess around with unplugging cables whenever I wanted to move my lightbox to the other room, so this would have been a very useful feature for me, and it would have made it easier to take over to my partner’s flat in the days before he moved in.  I’ve read that it has a much wider treatment angle than the older model, though I’ve not been able to confirm this.  When I talked to the National Light Hire Company, we discussed how it compared to the Lumie Zip, another popular LED lightbox, and they said that the new GoLite has a lot more features than the Zip and is generally more modern and high-tech.  They did not know whether it was easier to use, but judging from the user manual it’s still awkward.  It features a touchscreen, which I suspect may make it even more awkward when it comes to holding down two buttons at once, although at least the display looks nice and clear, in a blue that matches the bright light panel.  Abandoning the clamshell design of the older GoLite means that you no longer  have a back that can flip over to cover the screen. From having knocked mine onto the floor countless times over the years, I think the GoLite is sturdy enough that it doesn’t matter, and they do provide a nice slimline carry case.

The GoLite continues to be known as one of the highest-quality lightboxes around, and its small size and relatively short treatment time give it a big advantage over traditional fluorescent lightboxes.  It is no longer the only LED lightbox on the market, however.  Apart from the  popular Zadro (not available in the UK), all other LED lightboxes provide white light which peaks in the blue spectrum.  Blue provides a gentler light and possibly (but not necessarily) a slightly shorter treatment time, while white is likely to be more acceptable to anyone who is picky about their light colour, for instance if they need to make colour judgements.  Whether you prefer to pay more for the additional features and reliable brand name, or save money to get a more basic LED lightbox, is up to you.  If I were starting over with light therapy now, I think I’d buy a cheaper lightbox but make sure that it was from somewhere with a good returns policy in case of faults.

Bright light therapy: review of the Lumie Desk Lamp

January 27, 2010

The Lumie Desklamp provides 10,000 lux of light at 20 cm.  20cm is closer than is recommended for visual comfort, so at a more sensible distance this will be a lower-powered lightbox  This light uses 55W of power, so don’t think that just because it’s a species of low-energy bulb it’ll save you power compared to your ordinary desk lamp, but you do get a very bright light for that wattage.  The height is 45cm, the head measures 45 x 18cm, and the base 27 x 21cm.  At 2.5kg, this is a hefty piece of kit, though at least that means it won’t fall over.

This is the first bright lightbox I tried, five years ago when the variety of lightboxes available was not as great.  I found Lumie (then Outside In) while reading up on light therapy and was impressed by the amount of research on their website.  The free trial, where you pay upfront but receive a refund if you return it within 30 days (6 weeks for ME sufferers), was a definite bonus.  I spoke to Lumie and we decided that this would be best for my needs, mainly because it is equipped with a dimmer. I expressed concern that the light would give me migraine, as it is a fluorescent bulb.  Lumie said that they’d eliminated the flicker that is one of the reasons why fluorescent light is uncomfortable for many people.  I don’t know whether they failed to do so entirely or whether it’s just that fluorescent light is uncomfortable because of the colour of the light as well as the flicker, but it gave me dreadful migraines, so I had to return it.  Lumie advised me to try building up gradually from a short period on a dim setting, but it made no difference.  Having spoken to them again just now, they still seem to be under the impression that this is a lovely comfortable light that no one could possibly object to, which I felt was a bit too heavy on the sales approach rather than the medical realities, as intolerance of fluorescent light is typical of ME sufferers, migraineurs, many dyslexics, epileptics, and occurs with lots of other people.   Apart from that, I have always found their customer service to be extremely helpful and highly knowledgeable.  Everything went smoothly and I received a full refund.  I would not recommend this lightbox for anyone who is sensitive to fluorescent light, but if this does not apply to you, read on.

The Lumie Desklamp has been designed so that it can be used as a lamp as well as a therapeutic lightbox, which is unusual.  One benefit of this is that it is more discreet: if you’re using it in the office, it’s far less likely to cause your colleagues to ask what it is and then embark on a discussion of your health problems.  The dimmer function (the knob on the base) and the adjustable neck means that it is easier to adjust for comfort while you are using it, and that you can then turn it down and angle it away from you to use as an ordinary desk lamp.  It looks simple and well-made.

Fluorescent lightboxes range from 2,500 lux to 10,000 lux.  10,000 lux is more common these days, as it requires a shorter treatment time (which will still be longer than the treatment time required by an LED lightbox).  This lightbox uses 10,000 lux and at that setting Lumie recommend a treatment time of 90 min for SAD.  (How long is needed for sleep disorders is an entirely individual matter, but I know that I need longer than the recommended treatment time with my LED lightbox.  Use the SAD recommendations as a way of comparing different lightboxes.) An alternative is to use it at a medium setting for longer than the recommended time to get the same overall effect, which again will be a bonus for some people who are more sensitive to bright light.  This is a lightbox which requires you to be sitting by it for quite some time, so it’s one to use while in front of a computer in the morning rather than while gulping down breakfast before dashing out.

Apart from this, it’s a fairly basic lightbox, without the bells and whistles of the GoLite, for instance.  It doesn’t have timer function or a display which could show, for instance, a clock, the time left for light therapy, or the brightness.  About the only one of those I’d consider to be essential is the timer, but you can easily just use a timer on your computer or mobile phone, or buy a kitchen timer.  That said, it would be handy if the dimmer knob was a dial with numbers instead, as it is useful to know the exact effects the different levels of brightness will have on you, especially when you’re at the beginning stage of working out how long to use it for and what brightness setting you prefer.

One of the definite advantages of this model is that the light is positioned exactly where it needs to be, above the eyes.  If you look at this picture, the light is positioned pretty ideally.  I also find it is easier to have the light off the tabletop and up out of the way of desktop clutter, although with such a big lamp base there is less of an advantage here.

While I’m not madly keen on fluorescent light in general, as it really isn’t the best thing to be exposing your eyes to and will cause medical problems in a number of people, it does have one advantage over LEDs in that it covers a broad area, whereas LEDs are highly directional.  This plus the completely adjustable neck means that you really can have the light exactly where you want it.

It’s not the quickest lightbox to use, but if you are in the market for a fluorescent lightbox then I think this one has many advantages worth considering, and it is reasonably priced.

What colour light should a lightbox produce? White, blue, full-spectrum?

January 26, 2010

There’s rather a kerfuffle going on amongst lightbox manufacturers as to what is the correct colour for bright light therapy.  Older models of lightboxes all used white fluorescent light, and I think that what is going on is mainly about the longer-established manufacturers trying to hang onto the market, while the new ones are trying to persuade customers that their exciting new product is superior.  So on one side you have old-fashioned white lightbox manufacturers baying that blue light will ruin your eyes, and on the other you have blue lightbox manufacturers claiming that blue light is all that matters.

From all the research I’ve read, it does seem that blue light is the most effective bandwidth.  Blue light is, of course, contained in white light, and even the brightest lightbox will not be as bright as outdoor sunlight.  If thirty minutes in front of a little lightbox was enough to wreck everyone’s vision, we’d all be blind from the sun by now, even with modern indoor living. has written an excellent article on the purported dangers of blue light, concluding that unless you are at high risk of macular degeneration, you don’t need to worry, and to be sensible and not stare directly at your lightbox.

This spectrograph was produced by Apollo Health, the former manufacturers of the first blue lightbox, the GoLite, so it’s not from an unbiased source.  However, all the research I’ve read agrees that 470nm or thereabouts is the most effective bandwidth for affecting the circadian clock, and I’ve seen several spectrographs of fluorescent light (which is the  “standard full-spectrum” in this graph) that look the same.  Fluorescent light is spiky, which is apparently why it’s so harsh on the eyes, and even the full-spectrum versions don’t peak at 470nm.  Presumably this is why fluorescent lightboxes are a great deal larger than LED lightboxes and require longer treatment times.

Something interesting about LEDs is that the blue ones all seem to peak around 470nm naturally (warning: the page has lots of images and takes a long time to load).  This is why I suspect that using a standard blue LED bulb may not be as strong as a fancy lightbox, but it’s the right type of light and if used for longer, may have the same effect.  Typical white LEDs contain a broader bandwidth of light overall, but they turn out to peak around 470nm too (also a long page).  Here’s a typical example of a white LED bulb.

Some lightbox manufacturers claim that their LEDs are “blue-enriched white”, but frankly I think that they’re perfectly ordinary LEDs, the manufacturers are just cashing in on the fact that they happen to peak in the blue bandwidth.  (The advertising shenanigans of light therapy manufacturers can drive you demented at times.)

This means that white LEDs produce a cold light that most people don’t particularly like for domestic lighting, but it makes them ideal for bright lightboxes.  I’ve concluded that while blue light is the most effective, white LEDs are so close behind that you may as well choose your lightbox based on your personal preferences.  Some people find the blue light to be softer and less disruptive, other people find that they need white light so that they can look at colours properly (I once made the mistake of trying to do some embroidery with my GoLite on, and had to unpick it all afterwards as I’d picked up the wrong coloured threads), and a few people, such as my partner, just can’t get on with coloured light.  Choose according to your visual comfort and the other factors involved in choosing a lightbox, such as price, overall product quality and the various features that a lightbox can have.

If you prefer fluorescent lightboxes, there is the question of whether to go for normal or full-spectrum.  As far as I can tell, it doesn’t make any difference therapeutically, so go for whichever light you find to be most comfortable for your eyes, if you can even tell the difference.


Images courtesy of the LED Museum.

Bright light therapy

January 26, 2010

This is best known for treating Seasonal Affective Disorder, where it has been found to be as effective as anti-depressants, although the most effective treatment of all is to combine light therapy with anti-depressants.  What is less well-known is that bright light therapy is almost as effective in non-seasonal depression and is extremely useful for circadian rhythm disorders.

The main myth about bright light therapy is that it’s about full-spectrum lighting. It isn’t.  There are quite a few myths about light therapy which have been set up by rivalrous product manufacturers, and this one is an attempt to sell certain fluorescent lightboxes by claiming that they are in some way better than the others, which has somehow turned into the myth that all you need is a standard full-spectrum bulb.  The most effective wavelength for resetting the circadian clock is 470nm, blue light, so you need either blue light or white light which has plenty of blue in it.  (A couple of manufacturers favour green light for rather complicated reasons which you can read about here, where it’s concluded that they’re not worth trying unless you are at high risk of maculuar degeneration.)  The other important thing is the intensity of the light.  When a traditional fluorescent lightbox is used, 10,000 lux is preferred, though there are a few models around which use 5,000 or even 2,500 and require proportionately longer usage times.  Merely installing a full-spectrum/natural daylight bulb into your domestic light fittings will not make a blind bit of difference, as the light isn’t anywhere near strong enough.  Full-spectrum bright lightboxes were probably introduced because so many people find fluorescent light to be visually unpleasant, and there is a demand for a better colour temperature.  If you are going for a fluorescent lightbox, you may want to see if you can view a normal and a full-spectrum version to find out if you do prefer one or the other, but to be honest I think very few people are bothered about this, and that you’re better off using an LED lightbox if you don’t like fluorescent light.

Lightboxes are used for periods ranging from 15 min to 2 hours, depending on the type and the patient’s needs.  Unless you have Advanced Sleep Phase Syndrome, where you fall asleep too early in the day, the usual time of treatment is first thing in the morning, just after you get up (which for some people isn’t actually morning!), whether this is for sleep disorders or depression.  If you have DSPS or Non-24 Sleep-Wake Cycle, using bright light therapy in the morning has a high chance of stabilising your circadian clock and can even move it backwards so that you are falling asleep and waking up earlier.  I found that using a bright light box just after awakening immediately stabilised my sleep pattern at 24 hours instead of the 25 it had been on for years, and I started this four and a half years ago.  However, if my bedtime and waking time were too late, I needed to combine bright light therapy with a few days of sleeping tablets, taking the tablets an hour earlier each evening.  After that, the morning light therapy would serve to keep my waking time where it should be.  This has worked pretty well for me, although my sleep pattern wandered out of synch a few times a year and needed to be chased back.  Adding darkness therapy into the mix seems to have stabilised it completely.

There are two main types of lightbox, compact fluorescent and LED.  Fluorescent are the traditional ones and have been around for longer.  They are larger, require a longer treatment time, produce white light, and may cause medical problems for people sensitive to fluorescent light, such as migraine, visual problems, dizziness and so on.  The manufacturers try to dodge here and say that they have better ballast, but in my experience they’re just as bad as strip lighting and can cause nasty migraines. Perhaps they are better constructed, but since the light is so much brighter and it’s right by your face, it’s still more than enough to cause problems if you have difficulty with fluorescent light.  On the other hand, because they’re larger and the light is not as directional as LED light, they permit a little more freedom of movement when you are in front of them, though you still can’t move far away.  The light is also more likely to end up in the optimal position above your eyes, though since fluorescent lightboxes take much longer to use than LED lightboxes despite this, the advantage is probably cancelled out.  When looking at the stats for a fluorescent lightbox, most will say that they produce 10,000 lux, but you should also check at what distance that measurement is accurate.  If it’s 10,000 lux at 20 cm, that’s far too close to the light to be comfortable.  60 cm is more sensible, or alternatively just realise that you will need to use the lightbox for longer.  I think that this is how manufacturers are getting around the problem that everyone is told to look for 10,000 lux, but no one is quite sure what it really means and don’t realise that it’s only the measurement of the light intensity at a certain distance.

LED lightboxes have been around for a few years and may produce either white or blue light, which you can read more about here.  They are smaller and require a shorter treatment time.  Not everyone gets on with coloured light, and as the LED panel is composed of lots of little LEDs that look like dots, some people report getting spotting in front of their eyes, although I suspect that they were using the lightbox incorrectly.  You’re not meant to stare into it, you’re meant to position it at the side, or even better above your eyes, so that it hits your peripheral vision. LED lightboxes do have the disadvantage of needing to be placed more exactly and requiring you to stay in the same position, as the light produced by LEDs has a very narrow beam angle.  I use mine by my laptop or while sitting at my sewing desk, and while sometimes I need to prop up the lightbox to get it at the right angle, after that it’s fine.

I have a GoLite, previously made by Apollo and now made by Philips, which is a blue LED lightbox and very highly thought-of.  I also have a Lite-Pad, which is a cheap white LED lightbox I picked up on eBay for a tenner.  I use this one by my sewing table to save messing around with cables when I want to quilt during my morning lightbox stint, and also so that it doesn’t affect my colour judgement.  The GoLite does have a lot more bells and whistles, such as a clock and the ability to set both the light intensity and the length of time for up to three different preset programmes, but you’re paying a lot for them.  The Zadro looks like the best of the cheap lightboxes if you’re in the US, and indeed looks like a very good lightbox in its own right.  You can also buy combination lightbox/dawn simulators, of which more later.

There’s another type of bright light therapy around, known as the light visor, where the unit is placed in a sort of cap worn on the head, and the light is shone into the eyes from above.  Lumie makes a few, and there’s one which produces blue-green light around.  Their one advantage is that you don’t have to be tethered to your lightbox, you can move around. is doubtful about them, and I agree.

Since you can’t tell which lightbox you will get on with in advance, or even if it will work for you, and since these things are very expensive, find a company who will offer either hire-purchase (e.g. the National Light Hire Company) or a free trial (e.g. Lumie).  You may need to spend a while working out the right amount of time to use the lightbox for.

Of course, an entirely free alternative is simply to make sure you get outside for at least one hour every morning.  It doesn’t matter if it’s cloudy.  I’ve run into a woman online who managed to get the same effect by using a 150w fluorescent light (that’s actually 150w, not the equivalent to 150w incandescent), such as this grow light, in her overhead light during the whole day, not just for an hour.  This is far, far brighter than normal domestic lighting, and while it won’t save you energy and many people (especially with ME) will find it uncomfortable on the eyes and/or likely to provoke migraine, for some people it’s a good solution.

Another possible solution is to buy an LED bulb in white or blue and sit with it at a level just above your eyes for a couple of hours a day.  The blue bulb will be exactly the right wavelength, and while the white won’t have as much blue, white LEDs peak at the right wavelength so it will have a lot of it.  It won’t be as strong as a therapeutic lightbox but if you use it for long enough and keep it close to the top of your eyes, you may be able to get a decent result out of it.  If anyone tries this, do let me know how you get on.  I’ve got one of the blue bulbs which I’ve used for experimenting with moonlight simulation (this is popularly known as Lunaception and is meant to improve menstrual cycles, although for me it just wrecked my sleep), and I’ve noticed that I tend to feel wired after looking at it, and that using it for half the day was enough stimulation that I had a great deal of trouble sleeping that night.  So I reckon there’s quite a bit of potential with those little blue bulbs, and they’re better filtered than lightboxes so you don’t get spotting even if you look straight at them.

Are there any risks to light or darkness therapies?

January 26, 2010

There are risks to everything in life, but the risks for light and darkness therapies are minimal.  For starters, neither therapy interferes with medication, so that you may combine bright light therapy with antidepressants or darkness therapy with sleep aids if you need to.  Here are all the risks that I am aware of.

If you have macular degeneration, the current consensus seems to be that blue light may be damaging, though this appears to be largely theoretical.  This covers all bright lightboxes, as the ones which produce white light still contain blue light within the white, and in fact may contain even more light at the damaging wavelengths, which are actually below blue light.  You should probably avoid bright light therapy if you have macular degeneration, and will want to think about it carefully if you are at high risk of macular degeneration.  More information here, where the possibility of using green light instead is also discussed, and here.

Some lightbox manufacturers claim that their rivals’ products will cause untold damage in all sorts of ways.  Read the above link, which explains what’s really going on.  Short version: ignore them unless you already have, or are at high risk of, maculuar degeneration, in which case look into dawn simulation and/or darkness therapy instead of bright light therapy.  I find it extremely off-putting when manufacturers spread bad science in an attempt to knock the competition, but up to a certain level I think we just have to put up with it here, as they’re all doing it.

Bright light therapy may cause mania in bipolar disorder.  Read more about this here.  Changing the time of the light therapy may help, or just going for darkness therapy instead.

Traditional bright light boxes use very bright fluorescent light, and a number of people react poorly to fluorescent light (migraines, visual disturbances, nausea etc.)  Conditions which make this reaction more likely include migraine, ME/CFIDS,  MS, epilepsy, Meares-Irlen Syndrome, dyslexia.  Stay away from fluorescent lightboxes if you already know that you react badly to fluorescent light, and in general it’s a good idea to try before you buy with lightboxes anyway.

The other type of bright lightbox uses LEDs, either white or blue.  Some people don’t get on well with these either, although I think it’s a much smaller group.  Again, try before you buy, especially if you know that you’re sensitive to light. As the LEDs are displayed in a grid of little dots of light, some people report that they experience “spotting” in their vision.  It’s generally thought that these people were using the lightbox incorrectly, however.  It should be off to one side or above your field of vision, and you should not be staring directly at it.  This is how all bright lightboxes should be positioned, including fluorescent models.

For any problem relating to light sensitivity, you may be able to get past it by gradually increasing the brightness and length of time you spend in front of the lightbox, or using the lightbox for longer at a dimmer setting.  Take note of which lightboxes allow you to adjust the brightness if you think this will apply to you.  If you can’t handle bright light, consider dawn simulation and/or darkness therapy instead.

If you have ME/CFIDS or another condition which is highly debilitating, I now recommend making these changes gradually, just in case the shift in your sleep hormones sets anything off.  Start the darkness therapy one hour or even thirty minutes before bedtime, then gradually increase it.  Use a lightbox for short periods only to begin with, and on a dimmer setting if one is available and you are concerned about this.  I doubt that dawn simulation would cause any problems, but I’d suggest only introducing one change at a time.

A few people just don’t get on with coloured light in general or certain colours of light, including my partner, who reports reactions similar to the way I react to fluorescent lighting (including nausea).  This is more likely to occur if you have Meares-Irlen Syndrome and/or dyslexia.  Personally, although I have MIS I’m fine with blue and orange light.  It’s a highly individualised condition.  If this is the case for you, and it’s easily tested by buying a conventional coloured lightbulb that’s the same colour that you will be using, then go for a white lightbox instead of a blue one if you want bright light therapy.  Dawn simulation won’t be affected.  It may not be possible to practice darkness therapy fully, but at the very least you can dim the lights in the evening and avoid TV and computer screens.  Using brown-tinted glasses instead of orange glasses may work, as they don’t distort colours in the same way, although they’ll need to be fairly dark (brown is orange + black) to block blue light entirely.  There isn’t an option for coloured lightbulbs, but again, a brown screen filter for computers/TVs may be acceptable.

A disadvantage rather than a risk: if you do any sorts of art or crafts work, remember that colours will appear fairly different with a blue lightbox on and completely changed under yellow/orange lighting/glasses.  I try to plan my quilting so that I don’t need to judge colours for anything I do in the evenings, and have found that restricting my activities at that time helps me to wind down for sleep anyway.  Both fluorescent and LED white lightboxes give off rather a cold white light, which may make a difference if you usually use incandescent bulbs. I use a mixture of incandescent (yellowy white) and halogen incandescent (still a warm white but brighter than incandescent) bulbs on my sewing desk along with a white LED lightbox, and while I can see that the lights are a slightly different colour, it’s not causing problems in my work.

A friend of mine who suffers from depression and poor sleep reports that his mood drops significantly if he is in a dimly-lighted room, so if this is the case for you, darkness therapy is probably not an option.  On the other hand, this may be a short-term effect only.