Blue light at night inhibits melatonin

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Winter blues/Blue light

Post by overkees »

So, every year the same story repeats itself, over and over again.

It gets darker and darker, at shortest day you've got only 6-7 hours of daylight here in the netherlands. I keep doing fine for a while, but eventually I will get the 'winter blues' and in addition I will also have huge troubles to get out of bed.

Now there are some options, try to get as much daylight as possible or buy a so called blue light or a full light spectrum 5000-10000 lux lamp. The first option is very hard to do when you need to be inside for work or studies. Also, I've noticed, if it's grey outside and the sun gets blocked by clouds it almost makes things worse. Certainly when there is also a lot of rain fall.

So, I went to the stores and tried some of the lamps that were available. Now the full day light lamp was okay, but the blue light made me happy instantly! It felt like I was walking somewhere in a spanish village with a clear blue sky and alot of sunshine! I really feel warmth coming from it, but there is no heat involved! Awesome!

Now, my mother who has only a bit more trouble getting out of bed in the winter, and has no signs of depresseion, ever, disliked the lamp. It made her get a headache somehow.. So if you are going through with it, please test it first!

There is some research done in blue light and mood/circadian rhythm. Check it out:

What’s in a Color? The Unique Human Health Effects of Blue Light
Indoors illumination and seasonal changes in mood and behavior are associated with the health-related quality of life
Bright light improves vitality and alleviates distress in healthy people.
Non-Visual Effects of Light on Melatonin, Alertness and Cognitive Performance: Can Blue-Enriched Light Keep Us Alert?
Differential effects of light wavelength in phase advancing the melatonin rhythm

What I know, is that it gives me great energy boosts and helps to alleviate tiredness in the morning. In the evening I do get tired, something that is very hard for me to achieve. I just don't get tired in the evening.
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Blue light at night inhibits melatonin

Post by Kasper »

I seem to forget this very important fact from time to time, so this post not in the last place directed to myself.
I think one of the most important things for health is sleep.
Exposure to blue light in daytime, and avoidance of blue light at nighttime is therefore crucial. ... dark-side/
I would recommend to not look at this blue wai forum after 9 (or at least 2/3 hours before sleep).

"Light at night is bad for your health, and exposure to blue light emitted by electronics and energy-efficient lightbulbs may be especially so.
Until the advent of artificial lighting, the sun was the major source of lighting, and people spent their evenings in (relative) darkness. Now, in much of the world, evenings are illuminated, and we take our easy access to all those lumens pretty much for granted.

But we may be paying a price for basking in all that light. At night, light throws the body's biological clock—the circadian rhythm—out of whack. Sleep suffers. Worse, research shows that it may contribute to the causation of cancer, diabetes, heart disease, and obesity.

But not all colors of light have the same effect. Blue wavelengths—which are beneficial during daylight hours because they boost attention, reaction times, and mood—seem to be the most disruptive at night. And the proliferation of electronics with screens, as well as energy-efficient lighting, is increasing our exposure to blue wavelengths, especially after sundown.

Daily rhythms influenced by light

Everyone has slightly different circadian rhythms, but the average length is 24 and one-quarter hours. The circadian rhythm of people who stay up late is slightly longer, while the rhythms of earlier birds fall short of 24 hours. Dr. Charles Czeisler of Harvard Medical School showed, in 1981, that daylight keeps a person's internal clock aligned with the environment.

The health risks
Study after study has linked working the night shift and exposure to light at night to several types of cancer (breast, prostate), diabetes, heart disease, and obesity. It's not exactly clear why nighttime light exposure seems to be so bad for us. But we do know that exposure to light suppresses the secretion of melatonin, a hormone that influences circadian rhythms, and there's some experimental evidence (it's very preliminary) that lower melatonin levels might explain the association with cancer.

A Harvard study shed a little bit of light on the possible connection to diabetes and possibly obesity. The researchers put 10 people on a schedule that gradually shifted the timing of their circadian rhythms. Their blood sugar levels increased, throwing them into a prediabetic state, and levels of leptin, a hormone that leaves people feeling full after a meal, went down.

Even dim light can interfere with a person's circadian rhythm and melatonin secretion. A mere eight lux—a level of brightness exceeded by most table lamps and about twice that of a night light—has an effect, notes Stephen Lockley, a Harvard sleep researcher. Light at night is part of the reason so many people don't get enough sleep, says Lockley, and researchers have linked short sleep to increased risk for depression, as well as diabetes and cardiovascular problems.

The power of the blues
While light of any kind can suppress the secretion of melatonin, blue light does so more powerfully. Harvard researchers and their colleagues conducted an experiment comparing the effects of 6.5 hours of exposure to blue light to exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much (3 hours vs. 1.5 hours).

In another study of blue light, researchers at the University of Toronto compared the melatonin levels of people exposed to bright indoor light who were wearing blue-light–blocking goggles to people exposed to regular dim light without wearing goggles. The fact that the levels of the hormone were about the same in the two groups strengthens the hypothesis that blue light is a potent suppressor of melatonin. It also suggests that shift workers and night owls could perhaps protect themselves if they wore eyewear that blocks blue light. Inexpensive sunglasses with orange-tinted lenses block blue light, but they also block other colors, so they're not suitable for use indoors at night. Glasses that block out only blue light can cost up to $80.

Less-blue light
If blue light does have adverse health effects, then environmental concerns, and the quest for energy-efficient lighting, could be at odds with personal health. Those curlicue compact fluorescent lightbulbs and LED lights are much more energy-efficient than the old-fashioned incandescent lightbulbs we grew up with. But they also tend to produce more blue light.

The physics of fluorescent lights can't be changed, but coatings inside the bulbs can be so they produce a warmer, less blue light. LED lights are more efficient than fluorescent lights, but they also produce a fair amount of light in the blue spectrum. Richard Hansler, a light researcher at John Carroll University in Cleveland, notes that ordinary incandescent lights also produce some blue light, although less than most fluorescent lightbulbs.

What you can do
-Use dim red lights for night lights. Red light has the least power to shift circadian rhythm and suppress melatonin.
-Avoid looking at bright screens beginning two to three hours before bed.
-If you work a night shift or use a lot of electronic devices at night, consider wearing blue-blocking glasses.
-Expose yourself to lots of bright light during the day, which will boost your ability to sleep at night, as well as your mood and alertness during daylight. "
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Re: Blue light at night inhibits melatonin

Post by overkees »

I am very sensitive to blue light, thanks for the read.
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ADHD/blue light/sleep

Post by Kasper »

Many ADHD patients get melatonin precribed.
Avoiding blue lights (going outside) 3 hours before bedtime, or wearing blue blocking glasses may be a better option (or both).

Scientists at John Carroll University, working in its Lighting Innovations Institute, have developed an affordable accessory that appears to reduce the symptoms of ADHD. Their discovery also has also been shown to improve sleep patterns among people who have difficulty falling asleep. The John Carroll researchers have created glasses designed to block blue light, therefore altering a person's circadian rhythm, which leads to improvement in ADHD symptoms and sleep disorders.
How the Glasses Work
The individual puts on the glasses a couple of hours ahead of bedtime, advancing the circadian rhythm. The special glasses block the blue rays that cause a delay in the start of the flow of melatonin, the sleep hormone. Normally, melatonin flow doesn't begin until after the individual goes into darkness.
Studies indicate that promoting the earlier release of melatonin results in a marked decline of ADHD symptoms.
Better Sleep/Disease Prevention/Depression Relief
Major uses of the blue-blocking glasses include: providing better sleep, avoiding postpartum depression, preventing Seasonal Affective Disorder and reducing the risk of cancer.
An alternative to the glasses has also been developed in the form of night lights and light bulbs with coatings that block the blue light. Instead of wearing the glasses, an individual may simply turn off ordinary lights and, instead, turn on the ones with filters that remove the blue rays. The night light is a convenient "plug-in" device. The cost of the items ranges from approximately $5 for light bulbs and night lights to $40-$60 for glasses.
Advancing the circadian rhythm has been shown to improve both objective and subjective measures of ADHD symptoms in studies at the University of Toronto. Twenty-nine adults diagnosed with ADHD participated in a three-week trial.
Dr. Richard Hansler is the lead John Carroll University researcher in the development and uses for the blue-blocking glasses. He is one of the principal owners of a company that makes these new products.
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Re: Blue light at night inhibits melatonin

Post by Kasper »

I´m experimenting with inhibiting blue light from 9 p.m.
Being outside from 9 pm to 12 pm is probably one of the best options.
Although there is still quite much light in the city, I think it works very well.

I just bought this glasses:
Which should inhibit blue light.

Other options I thought about:
- having bulbs like this in the house: ... 40&bih=785
-candle light
- or: Image
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Re: Blue light at night inhibits melatonin

Post by fred »

Am going to try this one :

Better lighting...for your computer

"f.lux fixes this: it makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day.

It's even possible that you're staying up too late because of your computer. You could use f.lux because it makes you sleep better, or you could just use it just because it makes your computer look better. "
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Re: Blue light at night inhibits melatonin

Post by Oscar »

Looks interesting. Let me know what you think.
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Re: Blue light at night inhibits melatonin

Post by overkees »

Wow, that f.lux, I just tried it but it is very promising. It really is so smooth and soothing for my eyes. I don't have to be scared that I will stay up too long and not get tired due to the stress impulse from the super light screen of the computer. And yes, I am behind my computer quite late sometimes...

It takes some time to get used to (for me it took 20 minutes) but in the end it is super nice. I really appreciate that you found this helpful tool fred. I also installed it with a similar programme on my android tablet, it is called lux auto light or something. I'm really happy with this.
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Re: Winter blues/Blue light

Post by JaredFlowers »

Very effective information indeed, In winter there is huge problem of light and the information certainly helps me in finding right lights
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