Total darkness at night key to success of breast cancer therapy
sciencedaily.com
sciencedaily.com
This study was done on rodents, and the problem with the reporting of it is that rats are >100x more sensitive to this kind of light than humans are.
For white light, below about 5-10 lux, it is very hard to measure melatonin suppression in humans. This study finds that rats have significant melatonin suppression at 0.1 lux, which has been known since 1974 (Minneman et al) at least.
Still, don't sleep with the TV on, and don't see bright (room) light within a couple hours before bed, because that will actually suppress total melatonin by a significant percentage.
How do you avoid seeing bright light in the last few hours before bed?
Thank you for making f.lux, by the way. It's very cool, and I hope it gets more thorough biomed testing soon.
I searched for a long time to find a room light that avoided blue light and you have options with dimmer stands and certain bulbs. I ended up with some absurd-looking salt lamp that casts a soft orange light and has a dimmer (and allegedly releases magical ions that purify or clean the air -- not buying this last one).
Could you tell us about how the software works?
>Production of melatonin by the pineal gland is inhibited by light to the retina and permitted by darkness. Its onset each evening is called the dim-light melatonin onset (DLMO).
It is principally blue light, around 460 to 480 nm, that suppresses melatonin, proportional to the light intensity and length of exposure. Until recent history, humans in temperate climates were exposed to few hours of (blue) daylight in the winter; their fires gave predominantly yellow light. The incandescent light bulb widely used in the twentieth century produced relatively little blue light. Wearing glasses that block blue light in the hours before bedtime may decrease melatonin loss. Kayumov et al. showed that light containing only wavelengths greater than 530 nm does not suppress melatonin in bright-light conditions. Use of blue-blocking goggles the last hours before bedtime has also been advised for people who need to adjust to an earlier bedtime, as melatonin promotes sleepiness.
When used several hours before sleep according to the phase response curve for melatonin in humans, small amounts (0.3 mg) of melatonin shift the circadian clock earlier, thus promoting earlier sleep onset and morning awakening.
You want glasses that look orange (not pale yellow), like the $7 Uvex ones.
But thanks for the links on the existing screen films. Didn't know this was a thing already.
Of course, in general we need better sleep hygiene than what we do to ourselves now, and darkness at night would be one way. But for many it's not easy to just switch to a regime like that.
tamoxifen caused a dramatic regression of tumors in animals with either high nighttime levels of melatonin during complete darkness or those receiving melatonin supplementation during dim light at night exposure.
And cancer is not sensitive to tamoxifen but rather to estrogen (which tamoxifen is an antagonist)
I wonder what else we're disrupting with high levels of light. My crappy ass landlord but a giant fucking light right outside my bedroom. The problem is if I have blackout blinds to keep it dark at night, I won't wake up in the morning.
I did look into automating the drapes, ideally with a small electric motor on a timer. It seems like something you should be able to do for $200 or so, but I couldn't find gear that would actually just list the price...
I bought that thing on amazon back when it was on sale for like 40 quid and it works fine.
Perhaps automatic blinds would help? It sucks that your landlord did that.
thank you
OMG these "security lights" are horrible! I love walking around the countryside at night, but you have to be careful where you look if you don't want to be completely blind the whole time. It seems like everyone in the country has to have this giant 200W halogen bonfire burning all night. So many nights I've been tempted to have a bit of fun with the rifle. "Oh did I wake you up? I guess a turn-about is fair play."
Around here it's the electric company's fault:
http://www.lacledeelectric.com/homesecurity.aspx
If I had any pull with the PUC I would stop that "un-metered" crap before I stopped Ameren from raising rates to pay for a new reactor. (Because why should our investors have to actually make an investment?) The whole "security" aspect of these lights seems like baloney anyway. If that's the purpose, why not get a reflector and point the damn things down at the ground?
I walk outside at night all the time and it's nice to have it and certainly not blinding. Especially if you are more than a few dozen feet away from it. And no one has any good reason to be out there at night anyway.
Cities and towns are way worse offenders in this. Hundreds of lights at much higher intensities. Even parking lots and empty buildings get illuminated like its day time. It creates enough light pollution to block out the stars even. And it's payed for by taxpayers.
The idea that lighting contributes to security is questionable. Well-lit areas are easier to observe and navigate without calling attention to oneself. If it's your yard and you've lived there more than a month you should be able to walk around it blind-folded. Potential miscreants don't have that home-field advantage, and they appreciate your leaving the lights on. While they're out there you won't see them because you're inside watching TV. However if it were dark and they were shining flashlights or vehicle headlights around you might notice that. I'll allow that if there is an actual guard on attentive duty all night, lighting will be helpful.
I know that lights make you feel more secure, but that's just a reason to have them on while you're awake.
When you're walking outside at night "all the time", even though you don't have "any good reason to", you probably only see the ground in front of your feet. With all that artificial light, there's no way you're seeing any wildlife that isn't standing in the road, more than a few dozen stars, the landscape, etc.
Cities could certainly pollute less with light. Also, those who like bright outdoor lights on all night should move there.
Save your taxpayer angst for some other issue. The reason these lights exist is that power is really cheap when few people are using any power, which is generally true from bedtime to daylight. Of course the power company could be overcharging in any particular situation, but they wouldn't have popularized "security lights" in the first place if they hadn't had a bunch of generating capacity to dump.
Does total darkness also exclude dim lights like LEDs? So should you avoiding any electronics like clock radio, phone notification LED, ...?
Is having your eyes closed not enough to block out the light?
If it's about light on the skin: does lying under a blanket block it?
Thick black electrical tape is the best fix unfortunately.
I hope the blue light fad goes away soon.
Blue indicators should be deemed illegal. I had a laptop that had no less than 14 (fourteen) blue light sources on it. I had to unscrew the part and remove the LEDs.
If a faint light from under a door is able tu suppress melatonin, does this mean utilities such as f.lux are completely useless?
But, maybe it's not too much, since our eyes are probably very night-adapted when there's no other light source?
I found f.lux only a little helpful -- it wasn't until I added blackout curtains and started wearing blue-blocking glasses at night around the house that I noticed a strong effect.
Glasses are super annoying to wear though.
I suspect some people just try whatever bottle they grab first, and may find either no effect, or unwanted effects (excess grogginess/nightmares), and never try another dose.
EDIT: Apparently, the fact that I'm mocking the kind of "science reporting" that would turn this result into that headline wasn't screamingly obvious. I'm surprised; it's a phenomenon I've seen discussed often enough here.