Posted tagged ‘Light therapy’

Why an integrated approach?

January 26, 2010

There are a vast number of ways to approach sleeping problems.  Some are, in my opinion, utterly worthless.  I am not interested in purported treatments which are based on sham theories or have failed to stand up to scientific testing.  There are, however, a number of treatments which at present hover uncertainly between the alternative and orthodox worlds of medicine.

Light therapy is mostly on the orthodox side, for instance, although I have heard of a few rather dubious applications of it, such as a pulsed light mask that purports to treat migraine and PMS (there was one trial by the manufacturer, then it was never heard of again).  Bright light therapy for Seasonal Affective Disorder is by now very well established and offered as a routine treatment in many countries.  A smaller but still significant number of trials have shown that it is almost as effective for non-seasonal depression.  Bright light therapy for sleep disorders has been fairly well researched by now, but it is not yet as well established within the medical profession, although I think it is slowly getting there. Dawn simulation has generally been researched for SAD (it mostly comes out as nearly as effective as bright light therapy) and for sleep, in particular for people who struggle to get up in the morning.

Darkness therapy is a much smaller affair, perhaps because there is less money to be made by selling products for it.  It is generally researched by the same people who research light therapy and follows on from the same research, for instance into how different wavelengths of light are received by the eye and affect hormones within the body.  The main application at present is sleep, although there has been some interesting research concerning rapid cycling bipolar disorder.

Herbalism is a big sprawling system of medicine that has been going on for thousands of years and probably contains every plant known to mankind by now.  Various orthodox medications are based on herbal remedies, for instance aspirin comes from willow bark, and some of the most effective have become relatively well integrated into orthodox medicine in some countries.  Since a few herbs have been subject to a decent number of clinical trials and have stood up well in research, I am sticking to those.  Herbal medicines are generally, though not always, milder in action than orthodox medicines and with a lower rate of side-effects.  Sadly, they are still poorly regulated and it is important to read up on dosage and make sure that you are buying from a reputable manufacturer.

Then there are the therapies where research is rather scanty but not entirely absent, and where at least some of the effect may come from the therapy’s being pleasant and relaxing.  I don’t think that aromatherapy will cure a severe sleep disorder, but I’ve heard many doctors recommend lavender oil for mild insomnia, and having a nice warm bath with Epsom salts (magnesium sulphate) seems to be at a similar level.

Dawn simulation

January 26, 2010

Dawn simulation works by gradually turning on a light, generally 40w or 60w, over a period of time, most typically 30 min, in order to simulate a sunrise.  The light goes through your eyelids and moves your sleep stage to the point where it should wake you up naturally, meaning that you wake feeling as refreshed as you’re going to get and that hormones such as cortisol do what they’re meant to.  I find that when it wakes me up, it feels like I blink and I’m awake, rather than being dragged kicking and screaming into consciousness.  They all have backup alarms you can set just in case.  Most people don’t need them, but some do, and can still find that while the light isn’t quite enough to wake them up on its own, they do feel much better when they wake up.

As well as making it easier to get up in the morning, some research has found dawn simulation to be as effective or nearly as effective as bright light therapy for treating SAD, and it may work well for non-seasonal depression too.  This is despite the fact that it doesn’t use such bright light, just an ordinary bedside lamp or equivalent.  It’s thought to be something to do with the gradual increase in light having the effect.  The advantage over bright light therapy is that the treatment is over by the time you get up, you don’t have to tether yourself to a light box in the morning, but the disadvantage is that it may not be as effective.  Companies selling both tend to recommend it for mild SAD and bright light boxes for more severe SAD, I’ve noticed.

Dawn simulators also generally offer dusk simulation as well, where the light fades down gradually to help you get to sleep.  I think there’s some research around showing that it helps a bit with insomnia.  I’ve not really used this setting much as it’s less convenient, though I find it relaxing when I do.  I use dawn simulation because it helps stabilise my sleep pattern even further, and because it helps both myself and my partner to get up in the morning.

One common problem with dawn simulators is that they tend to buzz when the light is ramping up or down.  The best solution is to get one of the new energy-saving halogen bulbs, also called halogen incandescent, which are the same shape as standard incandescent bulbs and can be dimmed.  Not only will they save you at 30% on energy (42w is equivalent to 60w and so on, though I and many other people think they actually seem to be brighter than that) and last longer, but the light is good quality and they don’t buzz.  You can’t use fluorescent bulbs in a dawn simulator (I never recommend them anyway as the light causes problems for so many people), you can’t use the usual halogen bulbs, you can’t use LED bulbs if you’ve managed to find one, you can just use them with standard incandescent or energy-saving halogen.  This is for where you put in the bulb yourself: there are a couple of types of dawn simulator around using fluorescent or LED lights already built in.  If you get the type of dawn simulator which plugs into a lamp, again it has to be the sort of lamp which takes incandescent bulbs, and it can’t be a lamp which already has any sort of dimmer fitted, such as a touch lamp.  Just use an ordinary table, bedside or desk lamp.

There’s a new type of dawn simulator which is combined with a lightbox, such as this one (do read reviews, there are some poor quality ones out there by other manufacturers).  They may be a good solution for people wanting to try both dawn simulation and bright light therapy, but bear a few things in mind.  Firstly, it comes up to full lightbox brightness rather than the brightness of a 40w or 60w bulb, so that you will most likely be awake long before it’s anywhere near fully bright.  One solution could be to set a 90 minute sunrise and assume that you’ll be awake after, say, 30 min.  You need your dawn simulation to be by your bed but are unlikely to want to be using your bright light box by the bed, though if you read in bed in the morning or have your laptop close to your bed you could be OK.  The other point that occurs to me is that since the light is much brighter than is needed for dawn simulation, you could place it further away from the bed (e.g. by your computer, if it’s in the bedroom) and just point it in the right direction.  If I was starting light therapy all over again, I’d probably have gone for one of these and hoped that I’d be able to work something out once I’d fiddled with it enough.

I started off years ago with an all-in-one Bodyclock by Lumie where the lamp is built in, but even though it was a 60w bulb I found that it wasn’t bright enough for a reading lamp, plus Lumie often get slated for poor product build quality.  I sold it on eBay and bought myself a Sunrise System which plugs into a lamp or lamps of your choice, and vastly prefer it.  Mine  eventually became faulty and I sent it in for repair, where they reported that it had been damaged by a power surge (at which point I promptly bought a surge protector) and sent me a replacement which is slightly different from the older model.  They can take a bit of getting used to, and I think the company needs to continue tweaking them (though at the very picky level), but generally they’re excellent.  They have lots of useful features, such as being able to set the time individually for each day of the week.  We have it set to finish at 9 am Mon-Sat and 10.30 on Sunday, when my partner starts work later.  Actually he starts quite a lot later on Sundays, but I want to keep myself in a good routine while having a bit of a lie-in.

One of the great things about dawn simulators of this sort is that you can plug them into more than one lamp as long as you don’t exceed the total wattage, which in the case of the Sunrise System is 200w in the US and 300w in Europe.  That’s enough to hook it up to lights all over the bedroom if you like, though most people like to hook it up to a light on each side of the bed.  We’ve found that I get woken up better than my partner does by light, that he doesn’t like waking up to full light and generally prefers it to be dimmer on his side, that he still needs his alarms as he’s trained himself to respond to those, and that I take longer to get up once I’m awake, so that by the time he’s had a shower and got ready for work it’s about the time that I’ll be getting up.

So on my side of the bed, the dawn simulator is hooked up to my bedside light, which is a 40w equivalent low-energy halogen bulb in an anglepoise lamp that faces the wall, and on my partner’s side there’s a little 25w spotlight hidden behind a vase which points into the corner and is enough for ambient lighting.  My partner’s bedside reading light is independent of the dawn simulator.  The dawn simulation starts at 8 am, which is when the first of his three alarms go off.  He gets up at 8.30 when the light is up to half brightness, and I get up at 9 when the light is at full brightness.  As there are alarms going off from 8, I can be anywhere from awake to dozing to having fallen asleep again while the light is increasing, but it doesn’t seem to prevent it from being effective.  Occasionally I sleep in later than 9, but it’s probably only once a week, which for me is fantastic.  This helps keep my sleep stabilised even if I went to bed too late the night before.  I’m getting up earlier than I used to (even when I was using the lightbox), and it’s great being able to get up earlier in the morning and go to bed at the same time as my partner.

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.

Light and darkness: an overview

January 26, 2010

Arguably the biggest factors in sleep pattern regulation are light and darkness.  Humans evolved outdoors, getting plenty of strong daylight during the day and complete darkness at night, and averaging 12 hours of each.  It’s this light/dark signal that keeps the body on a 24 hour schedule: people who are completely blind almost all have sleep disorders, as the natural body clock runs on a 25 hour schedule for some bizarre reason and they don’t have the light/dark signals to keep it at 24 hours.  Now we sleep indoors, we mostly work indoors where the lighting is nowhere near as strong as sunlight, many of us barely get any   sunlight (and those of us with ME, or housebound due to other medical conditions, may not get any), and instead of following the natural pattern of darkness, we are in darkness only for the time we sleep and that may not even be complete darkness, and we will be under artificial light right up until bedtime.  This chart shows the relative light level from various outdoor and indoor conditions.  Even a well-lit office is still only 10% as bright as an overcast sky, and nighttime road lighting is 50 times as bright as a night with a clear full moon.  Our light/dark signals are all mixed up, and this is showing in the  high prevalence today of not only sleep disorders, but medical conditions which are affected by light/dark.

The very basic version is that bright light stimulates serotonin, and a lack of it can cause low serotonin levels and thus depression, as well as daytime sleepiness.  The main antidepressants used today are SSRIs, selective serotonin reuptake inhibitors, and there is a form of depression which is directly caused by low light levels during the winter, SAD (Seasonal Affective Disorder).  Cortisol is another hormone affected by light levels.  Melatonin is the hormone which makes us feel sleepy, along with a host of other roles in the body, and melatonin is produced when we are in darkness, which should average out to 50% of our time over the year but is now nothing of the sort.  The healthy pattern is to start producing melatonin a few hours before going to bed.  By using artificial lighting until right up to bedtime, melatonin production is inhibited, thus ensuring that we are less likely to feel sleepy when we go to bed, and also that we get less melatonin overall than we should.  All the research I’ve read agrees that we need to have melatonin coursing through our bodies for a certain number of hours per day, and that getting insufficient melatonin impacts on various areas of health, such as the immune system, as well as sleep.