Wearing blue-blocking eyeglasses a few hours before bedtime resets the internal clocks to an earlier hour.

This is an interesting idea:

A novel way to advance the circadian cycle has been proposed as a way to solve the problem associated with the early starting times of middle and high schools. It has been recognized for some time that teen age students do not really wake up until well past the time they physically arrive at school. Researchers at Brown University have found that the student’s blood contains large amounts of the sleep hormone, melatonin. Researchers at the Lighting Innovations Institute of John Carroll University are seeking funding to carry out a study to find out if their method of advancing the melatonin cycle will help.
It is well known that exposing the eyes to light during the evening delays the start of the flow of melatonin until after the person has gone into the darkness of the bedroom. Because the students like to stay up late working on their computers or watching television, their melatonin cycle is delayed. This means that in the morning, the cycle doesn’t end until well after they are in school.
Five years ago it was discovered that not all light causes suppression of melatonin, only blue light. This means that wearing glasses that block blue light is the same as being in darkness as far as melatonin production is concerned. Putting on blue blocking glasses at 9:00 P.M. will move the circadian cycle forward in time so that the melatonin flow is over before the student gets to school.
The blue blocking glasses have been tested as a means to help people with sleeping problems. Putting on the glasses a few hours before bedtime allows melatonin to be present at the time people go to bed. This avoids the delay in falling asleep experienced by many people. Using the glasses also has been reported to help people sleep more soundly.
As a bonus, having melatonin present for a longer time may also reduce the risk of cancer. Melatonin is known to fight cancer in at least three ways. It is a powerful antioxidant, counteracting the damaging effects of free radicals produced by radiation and chemical pollutants. Melatonin also blunts the cancer-promoting nature of estrogen, and it interferes with the metabolism of materials that cancer cells require as food
Wearing the glasses in the late evening results in getting close to the conditions of light and dark experienced before the invention of artificial lighting. Glasses that block the damaging blue light are available at a web site of a spin-off company formed by the John Carroll researchers, http://www.lowbluelights.com. Filters for TV and computer screens as well as safe light bulbs are also available.
The John Carroll University researchers are seeking funding to test the glasses on high schools students to see if moving their circadian cycle forward in time will result in better academic performance in early morning classes.

Well, they are asking funding for research. The underlying science exists, so this is not total hogwash. And they are upfront about the business opportunities for themselves, selling the glasses already even before they did the research.

14 responses to “Wearing blue-blocking eyeglasses a few hours before bedtime resets the internal clocks to an earlier hour.

  1. baby, you should try this so you can fall asleep faster.

  2. Wow, this is even better than chelation!

  3. This actually makes sense; the discovery that it’s the blue receptors in particular that reset melatonin is quite recent.
    I’ve wrestled with winter depression for decades, used super-bright lights and dawn simulation to reset for mornings (it’s about time, the days are getting short already).
    I’ve always had to work hard to dim lights and avoid even momentary bright light during the night. Our house looks a bit like a submarine — red LED nightlights abound. Since I got into my 50s, if someone turns on a white light, much brighter than full moonlight — then I’m awake — for the rest of the night, usually.
    Like any vegetable (grin):
    Amber would be a lot easier to live with than red. I’m going to try them.
    And I was about to install a few of these:

  4. This is pretty cool. I hope it works!
    As far as the antioxidant, does melatonin really behave that way in the body? I ask after reading a pretty scathing article in New Scientist about antioxidants:
    (subscription to New Scientist required)

  5. There is much more to adolescent phase-delay than the melatonin profile. The glasses may shift the melatonin profile but it is doubtful they will manage to shift everything else, e.g., the phase of the clock in the SCN that drives the melatonin profile. Will the melatonin feedback on the clock be sufficient to entrain the clock? I am not so sure it can.
    Melatonin is a strong antioxidant. That does not mean that taking pills will cure you of ageing and death.

  6. Interesting reading. A question strikes me: does this work in reverse? That is, will more blue light delay the cycle and thus help someone stay awake longer or help a person adapt quicker to a new time zone after travelling?

  7. >blue light
    Google for +”blue light” +”macular degeneration” for cautionary information. Search on “seasonal affective disorder” +”green light” for information on the alternatives that work. The sensitivity peak for the newly discovered receptor seems to be around 480nm.
    I tried a longer post and it hasn’t shown up; if it’s in moderation, favor that over this; else, maybe this will appear.
    Do be very careful with blue light; if you’re young enough not to have accumulated a lot over a lifetime, treat it like overloud noise.
    In other words — wear out only those senses you don’t expect to need when you’re old.

  8. Hank, there is nothing in my “Junk comments” folder, so the spam block must have swalowed it before it ever got to MovableType.
    Your points are well taken. The situation is more complex – that is why more studies are needed. One advantage of glasses that block blue light (in the evening) over exposure to a battery of bright blue lights (in the morning) is exactly that it does not have the possible negative consequences of regular exposure of the eyes to the intense blue light. As for the effectiveness – probably a combination of both (light in the morning and light-blocking glasses in the evening) would be even more effective than either treatment alone, but the glasses are certainly less dangerous.

  9. I’ve seen studies (abstracts, probably) about use of yellow goggles. For example for shift workers to avoid morning sunlight as they drive home to go to bed. I’d even thought to go hunting in all_those_boxes in the basement looking for my old ski goggles to try evenings.
    But then there is my (advanced) age. I’ve seen an abstract showing that older people can just forget about using blue light in the morning. It is no more effective than red and green. There was also an amusing interview explaining why white-haired old ladies sometimes color their hair blue. The young hairdresser says “Now that’s perfect,” but the old lady says “Oh, no, it’s still much too yellow.” Somehow older eyes don’t let in as much blue.
    It is quite annoying that almost all studies are done on the usual “eight healthy young men who have done no transmeridian travel nor night shift work the last three months”. We are not all healthy young men!
    old lady with DSPS
    . . . . .

  10. Hank Roberts

    Yes, the lens becomes yellower with age. The difference in color perception between my normal eye and my cataract-surgery eye (with an implant replacing the lens) is dramatic; much bluer through the implant. It’s an old one, so I can see ultraviolet in that eye, which is a serious risk for eye damage over time.
    Much info here — this is a page within a commercial site selling a green light for winter depression. I have no connection with it other than having found it and looked into it while searching for info on risks of blue. I will probably buy one; I think this is good science here.

  11. Does anyone have a nice lab available that can measure the spectrum for different light sources (and transmitted through different filters)?
    I’d love to know what the various “buglight” compact fluorescents pass.
    Got the tool? I’ll mail you the bulbs gratis, for the info.
    There are now a lot of pure yellow colored “twist” type bulbs.
    Nicer is a much more visually pleasant yellow-white GE “Bug light” compact fluorescent that has a polycarbonate shell plus yellow filter over the fluorescent. The latter approximate a “gaslight” yellow-green color in room lighting that’s actually quite tolerable for evening reading, and will block the UV as well.
    After 2 weeks using these — the sleep improvement my spouse and I have noticed is astonishing. We’d regularly read late at night with a small compact fluorescent light (very blue-white as they all are) and had trouble sleeping in recent years as we slowly replaced all our incandescents with compact fluorescents. Who knew?
    I’d love to know just what frequencies are emitted by the various “buglights” — the GE and one Feit brand floodlight both have a very tolerable ‘gaslight’ color.

  12. Belated followup answering my own questions for others who may be interested:
    Spectra published: http://www.ledmuseum.org
    — direct link: http://ledmuseum.home.att.net/spectra7.htm
    Starting point:
    Summary of what I learned in Comments at this thread:

  13. Hank Roberts

    18 months later followup: the low/no blue light at bedtime really has kept working.
    And I think sleeping through the night consistently also made the ‘winter blues’ much less difficult.
    We had inlaws including teenagers staying with us for a while, and I gave some of the yellow theatrical-filter material to them to put over their phones in the evening (it’s amazing how bright and relatively blue electronics screen backlights are, when you’ve eliminated the other sources).
    Result — they fell asleep early and slept well and remarked on the difference.
    We’ve added some 110v amber LED lights from this source:
    When bounced off a white ceiling, one or two will light a room up fine for getting around at night; as downlights they light up a good wide area for reading

  14. Why wouldn’t you use an anti-glare coating on your eyeglasses? I guess the blueblocker sounds like a good idea.