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Sleep And The Circadian Cycle

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#1 alternativista

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Posted 30 September 2011 - 09:11 AM

Something happened to all the links in this one during one of my many updates. I must have copied and pasted the displayed text rather than the html. I'll try to get them redone. Damn. there were some good ones.

Good Things for Sleep and Circadian Cycle

So much is timed by a proper wake sleep cycle, including hormone production and release, all kinds of hormones which are what control how your body functions. Affects melatonin/seratonin, insulin sensitivity, carb metabolism, hormone production and release, stress/mood/adrenal health, digestion... Lack of sleep plays just as important a role in developing diabetes as diet and obesity. You need to sleep well. And it requires regular exposure to bright light and to darkness.

Sunlight stimulates the pituitary and hypothalamus and thus influences the levels of nearly every hormone in your body. Thyroid, Seratonin/melatonin, D, sex hormones... I've seen lots of articles on this, but none specifying whether they mean you need to be in direct sun or just outside in bright light. But you need both so get a little direct sun, and a lot of bright outdoor natural light.
 
How much light?  Indoor lighting is rarely bright enough. You may think your office flourescents are bright, but they are nothing compared to sunlight.  Take your notebook or tablet outdoors.  Can you read it? That's because it's brighter out there.

Indoor lighting  is not bright enough to stimulate the necessary effects on your hormones and neurotransmitters. Brightness is measured in lux - with 1 lux being the equivalent of the light from 1 standard candle. Living room light in the evening is between 100 lux to 500 lux. Bright indoor light might reach up to 700 lux.
 
Compare that to natural lighting. Outdoor light at twilight is around 100 lux, a cloudy, rainy day around 2,000 lux, a sunny spring morning around 10,000 lux, a an  a bright sunny day 60,000 -100,000 lux.
 
On the other hand, even very dim lighting during your sleeping hours will stop your melatonin production.  Try to sleep in near total darkness. If you must have a nightlight, try an orange or red bulb

 

Good Habits

-A regular sleep schedule.
-Plenty of bright light, preferably sunlight, during the day. Get outside. Do it in the morning, before lunch and before you get that afternoon slump. At some point after lunch we experience a dip in core temperature that triggers melatonin production unless you are in the bright light.You could also go with it and take a brief siesta if that works for you and the length of the day, but get out in the light again after.
-Slow down and relax in evenings. No exercise within 3-4 hours of bedtime.
-Darkness at night. Dim lighting in evening. No light for sleep. Mimic nature as much as possible. Avoid the blue light from electronics. There's software that changes the color tone of your PC if you must use it late into the evening.
-Early bedtime. Again, mimic the natural pre-electricity age as much as possible.  Ideally go to sleep around 10-11pm.
-Don't turn on lights if you get up during the night. Get dim night lights for bathroom if you must.
-Exercise during the day to very early evening. Not within a few hours of bedtime. But do stretch and try some deep breathing before bed.
-Wear socks to bed. Something about overall body temp and circulation....
-Shower or bathe before bed. Also about body temp, but also just plain makes you feel better. I can't sleep without bathing. Even if I'm so tired I easily fall asleep, I'll wake in the middle of the night feeling icky.
-Eat dinner early and have only a very small snack of some sleep enhancing food near bedtime. see below for foods.
-Healthy adrenal function - so manage stress, exercise and sleep!

Melatonin -
-Supplement - a couple of milligrams at bedtime may be helpful for those with sleep problems.
-Habits to improve melatonin production:
--Boosting seratonin production in the daytime via bright light and the necessary nutrients will improve melatonin production. Seratonin is converted to melatonin when triggered by darkness. That process stops when you are exposed to light. And the whole process is muddled when you spend your days in dim indoor lighting. What you want is a surge of melatonin at night for sleep.
---Nutrient precursors to seratonin are methionine, folate, B12, B6, TMG (betaine) and zinc, C and maybe some calcium and magnesium. And of course, amino acid tryptophan. From here (lost the link, sorry)Potassium is involved in conversion (one of the missing hyperlinks).
---Bright light exposure.
---Exercise
--Darkness triggers conversion of seratonin to melatonin in preparation for sleep.
--Omega 3 EFAs

Nutrients
-Magnesium - relaxes muscles as well as being precursor to seratonin
--SAMe - methionine and magnesium supplement
--ZMA supplement - zinc, magnesium, B6 supplement
--Epsom Salt baths - full of magnesium and sulfur, absorbs through skin
-(I've also seen thiamine (B1) and taurine recommended. Didn't find reasons for the thiamine, only that a deficiency is found in people with sleep problems and supplementation helps. The taurine has a sedative affect despite being in all kinds of energy drinks, due to it's role in the production of GABA a neurotransmitter linked to sleepiness)

Diet:
-Foods containing tryptophan or melatonin: banana, milk, oats, rice, pumpkin/sunflower seeds and any complete protein. Early in the day to produce seratonin.
-Foods containing seratonin (and the right ratio of other stuff) - plantain, banana...
-10 foods to help you sleep and more good info in the next few posts.
-A little glucose/fructose - And I do mean a little. Teaspoon of honey, small banana, etc. Does many things. Releases a little insulin to get tryptophan to the brain where it's converted to seratonin. Fuels liver which is part of that process as in the hibernation diet.
-Calcium and potassium containing foods.

-Camomile Tea- enhances your calm
-Valerian Root - Ditto
-Green tea - richest source of L-theanine supports the production of GABA and helps deal with stressors, but it has some caffeine, so quit drinking it in the afternoon onwards.

Pretty good paragraph on wikipedia seratonin article:
QUOTE
Serotonin levels can not be increased by diet or supplements of tryptophan alone. For example, increasing foods rich in tryptophan (eg, meats, proteins) does not increase serotonin levels, due to competition with other amino acids.[49] What is required to increase serotonin production is an increase in the ratio of tryptophan to phenylalanine and leucine. Fruits with a good ratio include dates, papaya and banana. Foods with a lower ratio inhibit the production of serotonin. These include whole wheat and rye bread[50] Much research has indicated that vigorous aerobic exercise improves mood, believed to be facilitated by an increase in serotonin levels.[51] Research also suggests that eating a diet rich in whole grain carbohydrates and low in protein will increase serotonin by secreting insulin, which helps in amino acid competition.[49] However, increasing insulin for a long period of time can sometimes onset insulin resistance, which is related to obesity, type 2 diabetes, and lower serotonin levels. It is also believed that muscles use many of the amino acids except tryptophan, allowing men to have more serotonin than women.[52] Bright light therapy is another popular method which prevents the conversion of serotonin to melatonin.[53] A similar effect is obtained by spending more time in natural sunlight. Recently, acupuncture has been shown to stimulate the release of serotonin in lab animals.[54] Myo-inositol, a carbocyclic polyol present in many foods, is known to play a role in serotonin modulation.[55"]


Myo-inositol, a carbocyclic polyol present in many foods (whole grains, nuts legumes and other seeds and many fruits), is known to play a role in serotonin modulation.[55]


DHEA - steroid hormone that keeps us asleep. Produced in the adrenals and stimulated by melatonin.

Prolactin -

Avoid progestin - synthetic hormone in birth control, inhibits seratonin production.

Note exposure to light also affects carb metabolism

Article on sleeps effects on glucose metabolism and endocrine system, in other words, hormones:
http://www.scienceda...91025075844.htm And you'll find links to plenty of related articles.

Interesting related threads:
http://www.acne.org/...ge-t245268.html

http://www.acne.org/...ul-t243340.html


Edited by alternativista, 18 February 2013 - 06:58 PM.


#2 alternativista

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Posted 30 September 2011 - 09:39 AM

Sleep Cycle Alarm clock and Smart Alarm clock iPhone apps: supposedly tracks your movements during sleep and the alarm goes off during a period of light sleep to wake you more naturally. I haven't tried it yet as I don't need an alarm clock. I think they also provide data on how you sleep that might help identify problems. and more.

Other more expensive gadgets:
http://today.msnbc.m...717542#44717542


F.Lux software
Free software to change the color spectrum of your computer display. Blue/green in daylight (and your PC and TV screen, LEDs and flourescent lighting) stimulates seratonin and supresses melatonin production. Red/orange light (fire, candlelight) does not suppress melatonin production. Around 6 or so pm, this software changes your PC display to a reddish hue so it does not interfere with your sleep. http://stereopsis.com/flux/

Edited by alternativista, 06 October 2011 - 04:47 PM.


#3 alternativista

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Posted 06 October 2011 - 04:40 PM

Dawn simulating alarm 'clocks' To wake naturally, with light. Including Do-It-Yourself versions using timers and lamps.

http://www.acne.org/...-dawn-simulator


There's more here in this thread:
http://www.acne.org/...54#entry2165654
Mark Sisson recently blogged about biphasal sleep, which we spent some time arguing about in that thread. But, none of our arguments were about whether or not sleep was important even though some participants seemed to think so. They were about what counted as good sleep.

The gist is that people without electricity don't/didn't tend to sleep for 8 hours straight. They tend/ed to sleep early, then wake at some point during the night to talk, eat, visit neighbors, think, have sex, etc. Then go back to sleep. Even in European cities. There are references in centuries old literature to first and second sleep.

The MDA blog: http://www.marksdail...biphasic-sleep/ Cites references and makes the point that you shouldn't worry that you wake during the night. Good sleep doesn't have to mean 8 hours non-stop. Don't stress that you can't achieve that.

I nearly always wake up once during the night. In fact, I've always hated whenever I slept straight through. I usually woke feeling like I just went to bed and hardly slept at all. But I do think you need at least 4-5 hours straight to go through all the phases of sleep. But regardless of what mattress and pillow salesman tell you, 8 hours without waking isn't necessarily natural or required.

Other sleep thread with some good tips:
http://www.acne.org/...ep-t215896.html

Other MDA post:
http://www.marksdail...ove-your-sleep/


Edited by alternativista, 18 February 2013 - 07:00 PM.


#4 OlympusMons

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Posted 07 October 2011 - 10:36 AM

Interesting posts, alternativista!


The gist is that people without electricity don't/didn't tend to sleep for 8 hours straight. They tend/ed to sleep early, then wake at some point during the night to talk, eat, visit neighbors, think, have sex, etc. Then go back to sleep. Even in European cities. There are references in centuries old literature to first and second sleep.


Wow, this is interesting! Do you believe I feel like I always had that tendency?
When it comes to 9 or 10pm, I always have the will to go lay a bit in my bed! And if I do (which is rare, but sometimes happens) I fall asleep in a way that feels much more natural and pleasurable than when I usually go to bed, around 12pm/1am. Then, I wake up by 3am/4am, I stay awake reading or watching some videos, listening to music, than I go to sleep again by 5am/6am, and sleep till 8am/10am.


The only thing I don't agree with you are the supplements.
I think there's absolutely no need for them, as long as you eat average quantities of fruits, vegetables and some animal foods. These will largely supply you with everything you need. You won't be healthier for consuming extra-magnesium, extra-zinc, extra-vitaminA etc. And some supplements contain really big doses, like 100xRDA, so that can also be dangerous. Most supplements also contain substances that can trigger acne, like gelatin.

Edited by OlympusMons, 07 October 2011 - 10:37 AM.


#5 alternativista

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Posted 07 October 2011 - 12:21 PM

I'm not recommending the supplements. Those are just beneficial nutrients that some may want to try.

And I disagree with you. It is quite difficult to get many nutrients. And while I am not in favor of mega dosing anything, the RDAs of many nutrients are way to low. C and D for example. Most animals make their own C and they make thousands of mgs per day. More if sick or injured. And you need several thousand IU of D per day as well. Ideally from the sun, but not everyone can meet their requirement that way. And I definitely recommend supplementing Magnesium in some form or another. Epsom salt baths is a great way for those that like to take baths.

#6 OlympusMons

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Posted 07 October 2011 - 01:09 PM

It is quite difficult to get many nutrients. And while I am not in favor of mega dosing anything, the RDAs of many nutrients are way to low. C and D for example. (...) And you need several thousand IU of D per day as well. Ideally from the sun, but not everyone can meet their requirement that way.


I don't agree that it is quite difficult to get many nutrients. It might be for "normal"/junk dieters, but not for people who do healthy and natural diets, based on fruits and vegetables.

I agree that the RDAs of many nutrients might be way to low, such as others are in my opinion too high, like calcium and zinc.
But if you eat plenty of nature's food, foods that we humans are desing to eat: fruits, nuts, veggies and animal foods, and as long as those foods have a minimum of good quality, I don't think you could easily lack any nutrient. Even my doctor says specific-nutrient deficiency is quite rare.

For eg, if you eat fruits everyday, you will hardly lack vitC, fruits are loaded with it. I get about 1g of C per day, RDA is 60mg.

About vitD... http://health.usnews...d-for-vitamin-d
"If you're fair skinned, experts say going outside for 10 minutes in the midday sun—in shorts and a tank top with no sunscreen—will give you enough radiation to produce about 10,000 international units of the vitamin."
Is it so hard to spend 10min in the sun? In the winter vitD can be stored. So, if someone doesn't even spend 10min in the sun per day, I think that will have other consequences on health other than low vitD...!

To conclude, I think if you live naturally (eat nature's food, get some sunlight, some decent sleep) I don't see why would you need anything else.

#7 alternativista

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Posted 07 October 2011 - 01:18 PM

Studies on sleep, light and circadian cycle:

Daytime exposure to bright light, as compared to dim light, decreases sleepiness and improves psychomotor vigilance performance. http://www.ncbi.nlm....pubmed/14572122


[Effects of dim or bright-light exposure during the daytime on human gastrointestinal activity.
http://www.ncbi.nlm....pubmed/12638695

These results support our hypothesis and indicate that dim-light exposure during the daytime suppresses the digestion of the evening meal, resulting in malabsorption of dietary carbohydrates in it.

 


Bright light exposure during the daytime affects circadian rhythms of urinary melatonin and salivary immunoglobulin A. http://www.ncbi.nlm....pubmed/10373104 Abstract says 'These results are consistent with the hypothesis that bright light exposure during the daytime enhances the nocturnal melatonin increase and activates the mucosal immune response.' Which basically means it's good for IgA antibodies that work in mucus linings that are an important part of your immune system.

Protein-source tryptophan as an efficacious treatment for social anxiety disorder: a pilot study. http://www.ncbi.nlm....pubmed/18066139 This study uses the seed from some gourd as their tryptophan source, but they don't say what it is in the abstract. I imagine they plan on making a pill to sell us.

Oral zinc augmentation with vitamins A and D increases plasma zinc concentration: implications for burden of disease. http://www.ncbi.nlm....pubmed/17171460 - But you want your body to make as much of your vitamin D as possible. Get some sun while out in the daylight.


Edited by alternativista, 26 February 2013 - 11:19 AM.


#8 alternativista

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Posted 11 October 2011 - 04:27 PM


It is quite difficult to get many nutrients. And while I am not in favor of mega dosing anything, the RDAs of many nutrients are way to low. C and D for example. (...) And you need several thousand IU of D per day as well. Ideally from the sun, but not everyone can meet their requirement that way.


I don't agree that it is quite difficult to get many nutrients. It might be for "normal"/junk dieters, but not for people who do healthy and natural diets, based on fruits and vegetables.

I agree that the RDAs of many nutrients might be way to low, such as others are in my opinion too high, like calcium and zinc.
But if you eat plenty of nature's food, foods that we humans are desing to eat: fruits, nuts, veggies and animal foods, and as long as those foods have a minimum of good quality, I don't think you could easily lack any nutrient. Even my doctor says specific-nutrient deficiency is quite rare.

For eg, if you eat fruits everyday, you will hardly lack vitC, fruits are loaded with it. I get about 1g of C per day, RDA is 60mg.

About vitD... http://health.usnews...d-for-vitamin-d
"If you're fair skinned, experts say going outside for 10 minutes in the midday sun—in shorts and a tank top with no sunscreen—will give you enough radiation to produce about 10,000 international units of the vitamin."
Is it so hard to spend 10min in the sun? In the winter vitD can be stored. So, if someone doesn't even spend 10min in the sun per day, I think that will have other consequences on health other than low vitD...!

To conclude, I think if you live naturally (eat nature's food, get some sunlight, some decent sleep) I don't see why would you need anything else.


I agree that everyone should get as much nutrients as they can from food and D from the sun. Particularly the D as there's evidence that only vitamin D sulfate, which we must make, performs some of the vital functions.

But not everyone is fair skinned and lives in a latitude where there is enough UVB light. Also, most of us are working indoors and really can't bring our halter tops and shorts along to the office. And I personally am not going to sit outside midday in the brutal summers where I live. I do however eat lunch outside as much as possible the rest of the year. But not nearly naked.

And of course that lack of light has other consequences. I wrote about some of them right up there in the first post.

And yeah, vitamin C is easy to get if you eat plenty of fruit and mostly raw veggies. That's one. And 'not deficient' isn't the same as optimal. My days don't always go as planned and i don't always manage to eat all that I had intended to.

Edited by alternativista, 11 October 2011 - 06:23 PM.


#9 OlympusMons

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Posted 13 October 2011 - 08:51 AM

Ok, your opinion, I respect it.

Still I find it curious that some people might not have 10min (ok, 20/30 if you're not fair skinned) to spend in the sun only in the hot weather days (cause it stores for cold weather days), where you can easily wear a t-shirt, a top, go to the park/street and undress your workwear for 20min... But in the other hand have money and time to go buy supplements and to go to doctors.
Note: if you go to the beach one day, even for a few hours, you'll produce hundreds of thousands of mg's of vitD...which can be stored!


About C, I think optimal quantities of fruits and vegetables provide optimal vit C. I never studied vit C but I honestly don't think we need more than like 1g for optimal body function. But if you want more, you can get it easily from natural sources. Just buy a few pounds of acerola, dry it, and in one bite of dried acerola you'll have hundreds of mg's of vitC :D

My days don't always go as planned and i don't always manage to eat all that I had intended to.


That's because you depend on cooking. If you eated a raw food diet you could eat whatever you want anytime.

Edited by OlympusMons, 13 October 2011 - 08:54 AM.


#10 alternativista

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Posted 08 November 2011 - 09:52 AM

Gadgets to prevent blue spectrum light exposure at night.

Doctor Oz had some useful advice about sleep and the circadian cycle with some gadgets and suggestions like orange light bulbs and an orange screen filter to block light in the blue spectrum that suppresses melatonin conversion. But unfortunately, all they have on the website is a clip of the segment from the show. (A huge pet peeve of mine. Why do they always say they have more information on the website when all they are going to do is put a clip that I've already seen!) Clip: http://www.doctoroz....-best-bets-pt-3

Here's a link to a vendor of orange computer screen filters, bulbs, eyeglasses, etc: http://www.mdlifeinc...4esnb7687ro5h77 You might also try going to a photography store and ask for orange/red gels which are sheets of celophane or something that they put over lights. You could cut to fit nearly anything.

Daylight is full of blue spectrum light. That's what you should be exposed to in the daytime. At night there should be little light, but natural things like fire are in the red spectrum which do not interfere with the melatonin cycle. This is what you want at night.

Exposure to bright light prevents the secretion of melatonin and darkness promotes it. Your pineal gland detects bright light in the daytime and suppresses melatonin conversion. Dim light starts the conversion. Ideally, within one to two hours after the sunset, you begin to feel drowsy as the melatonin levels rise. This is the body’s signal to go to sleep. By midnight your melatonin levels peak and there is a gradual decline in melatonin levels after midnight. You ideally want a surge that occurs in the evening after the sun sets to prepare yourself for a good night's sleep. But spending all day indoors muddles up this process. Indoor lighting is rarely bright enough to fully suppress melatonin.

The ideal and most productive sleep time is between 10Pm and 2am (with some variation for time zones and season)

At 10 p.m., your body goes through a transformation following the rise in melatonin production. This transformational phase of sleep is associated with an increase in the “internal” metabolic activity that is responsible for the repair and restoration of your body. A reduction of your mental and physical activity is necessary for this 10 p.m. shift to occur. If you are still awake, the “second wind” phenomenon occurs at 10 p.m. because there is a rise in mental activity and energy at this time. However, the true value of the “second wind” can only be experienced if you are asleep by 10 p.m.


Edited by alternativista, 08 November 2011 - 10:34 AM.


#11 alternativista

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Posted 19 December 2011 - 02:06 PM

Study on the effects of lighting on school children:

http://www.longnatur...ibrary2.asp?A=5

Discusses spectrum, amount and all kinds of health issues.

#12 alternativista

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Posted 18 February 2013 - 05:12 PM

Mercola article on how diet can affect your sleep:

 

http://articles.merc...mpaign=20130218

 

 

 

While the study was only able to generate hypotheses about dietary nutrients that may be associated with short and long sleep durations, it did yield some interesting data. Participants were grouped into four sleep groups:

  • Very short (less than 5 hours a night)
  • Short (5-6 hours)
  • Normal (7-8 hours)
  • Long (9 or more hours)

Here are some of the dietary characteristics uncovered about each sleep group:

  • Very short sleepers: Had the least food variety, drank less water and consumed fewer total carbohydrates and lycopene (an antioxidant found in fruits and vegetables).
  • Short sleepers: Consumed the most calories but ate less vitamin C and selenium, and drank less water. Short sleepers tended to eat more lutein and zeaxanthin than other groups.
  • Normal sleepers: Had the most food variety in their diet, which is generally associated with a healthier way of eating.
  • Long sleepers: Consumed the least calories as well as less theobromine (found in chocolate and tea), choline and total carbs. Long sleepers tended to drink more alcohol.

As for what the data means, researchers aren’t yet sure. They’re using it as more of a starting point from which to base future research:



#13 onefatalgoose

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Posted 19 February 2013 - 09:31 PM

Great thread alternativista.  Something i really need to be better at.  Way too much stimulation in my life



#14 alternativista

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Posted 26 February 2013 - 11:17 AM

High Potassium Treatment Resets the Circadian Oscillator in Xenopus Retinal Photoreceptors 
Minoru Hasegawa 
Department of Biology and Biochemistry, University of Houston, Houston, TX, hasegawa@uh.edu 

Gregory M. Cahill 

Department of Biology and Biochemistry, University of Houston, Houston, TX 

In vertebrate retina, light hyperpolarizes the photoreceptor membrane, and this is an essential cellular signal for vision. Cellular signals responsible for photic entrainment of some circadian oscillators appear to be distinct from those for vision, but it is not known whether changes in photoreceptor membrane potential play roles in photic entrainment of the photoreceptor circadian oscillator. The authors show that a depolarizing exposure to high potassium resets the circadian oscillator in cultured Xenopus retinal photoreceptor layers. A 4-h pulse of high [K+] (34 mM higher than in normal culture medium) caused phase shifts of the melatonin rhythm. This treatment caused phase delays during the early subjective day and phase advances during the late subjective day. In addition to the phase-shifting effect, high potassium pulses stimulated melatonin release acutely at all times. High [K+] therefore mimicked dark in its effects on oscillator phase and melatonin synthesis. These results suggest that membrane potential may play a role in photic entrainment of the photoreceptor circadian oscillator and in regulation of melatonin release.



#15 alternativista

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Posted 28 June 2013 - 03:21 PM

Using tablets/PCs at night.

 

There are other apps that you can get for Android tablets to shift the display away from the blue spectrum.  One is called Twilight that works automatically according to your timezone  much like f.lux on your PC.  Another is called Easy Eyes.

 

As far as I know, Apple won't allow any developers an API to alter the display settings.  Unless you jail break your iPad.  I look into it once in a while, but I see people who claim they did it and 'bricked' their iPad.  I have no idea how likely that is to happen. 

 

I bought these orange safety glasses.  I hate wearing glasses, but as far as glasses go, these aren't too uncomfortable.

http://www.amazon.co... safety glasses



#16 uncle buck

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Posted 29 June 2013 - 07:40 AM

I use F.lux too, it's really subtle. When I have it on this monitor and open a second screen without it at night, it's like the sun just came up.



#17 alternativista

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Posted 21 December 2013 - 05:07 PM

Bright light exposure reduces your sweet tooth. http://www.ncbi.nlm....ubmed/23926241/

#18 alternativista

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Posted 23 December 2013 - 11:51 AM

This is a set of color changing LED bulbs that you can program with your smart phone. If  you could use it to create a dawn simulating wake up light, plus remove the blue from the spectrum in evening until morning, they could be cool.  Expensive though. http://reviews.cnet.com/smart-home/philips-hue-connected-bulb/4505-9788_7-35826679.html  There are some other cheaper options mentioned in the article.



#19 alternativista

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Posted 26 December 2013 - 08:29 AM

Article cutting study on effects of hospital lightin on pain, mood, sleep, and thus recovery. Note the lux levels of outdoor light vs what you think is bright office light.

Hospital Room Lighting May Worsen Your Mood and Pain http://articles.merc...m-lighting.aspx

Edited by alternativista, 26 December 2013 - 08:30 AM.





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