This (older) article says: "we don't spend that much time staring at the sun". But just seeing the blue sky gives your retina about 50x the dose of blue light (hazard) as a normal LED display.
Blue light hazard is generally considered to be "reciprocal" which means for most doses, you can measure total energy (power * time). So it is easy to argue that one hour spent outdoors (not staring at the sun, just doing normal stuff) gives you more dose than 12 hours at a computer. So for light seen during the day, nobody has yet shown that seeing a computer is harmful, and the risk should be lower than spending an hour outdoors.
At night, it's another story, and there is not clear evidence here. The retina experiences daily circadian rhythms, and so risks to your eye may be enhanced by bright light seen at night. Less light at night is good for your circadian clock, and it is almost certainly good for your eyes too.
The original claim is that exposure after sunset upsets your circadian rhythms. Now it's been twisted into "OMG! blue light will blind you". The good news is that this will hopefully put the nail in the annoying blue indicator LED coffin. All the cool kids are using white and RGB LEDs now.
This is confusing to me, would love if someone helped elucidate the details. My previous understanding was that bluelight is harmful because bluelight visually interferes with the body's circadian rhythm by leading the body to believe it's still daytime when it may not be.
This article says that "any bluelight is bad", is that incorrect? I don't understand, isn't bluelight measured as light on the 450nm range of the electromagnetic spectrum, whereas visual sunlight ranges from 400-700nm? So, is the thesis that light at 450nm from the sun is only emitted when the sun is highest in the sky, for a few hours a day, whereas bluelight from screens is ever present—causing the circadian rhythm to go out of whack (?).
The article also states that blue light on any part of the body may cause mitochondrial damage. I wonder if the most proactive biohackers would be inclined to wear long-sleeves at non-peak hours to counter this problem. [0]
Maybe this is why Dave Asprey is seen always wearing his blue light blocking glasses, even during daylight hours.
I am also not so inclined to dismiss this data because it only addresses fruit flies. It seems natural to believe that the closer we get to following the circadian cycles we evolved alongside with, the more likely our bodies are to behave optimally. Sure, we may be more resilient to these types of stressors than fruit flies, but, we already know that obeying circadian cycles is a key component to achieving better health, and the work of this paper just seems to push that idea a bit further than we may have originally been lead to believe. It doesn't take much of a stretch of the imagination to guess about how these factors could affect us.
I've been listening to the Huberman Lab podcast, and he seems to think that blue light filtering during the day is a terrible idea in terms of your body's natural rhythms.
I’ve been listening to Andrew Huberman’s podcast lately. He’s a neurologist and ophthalmologist at Stanford. Something that comes up a lot is how much artificial light, especially the blue light of screens, affects the eyes, brain, and circadian rhythm. Research has even shown a significant impact on hormone levels.
Because of this, I don’t see reading a book on a phone as equivalent to a paper book, or reading news online as a equivalent to a newspaper. The content your brain is processing may be the same, but it has a very different impact on your body and mental state, especially at night. So I think it’s wise to differentiate screen vs. non-screen activities and be more careful about doing the former in moderation, or perhaps only early in the day.
I think it's important to recognize that this is far from the only study pointing to this, and that similar problems are associated with CFL's.
For example, here is a 2014 study, "White Light–Emitting Diodes (LEDs) at Domestic Lighting Levels and Retinal Injury in a Rat Model" http://ehp.niehs.nih.gov/1307294/
Links to eye toxicity, macular degeneration, and blindness are not the only problems associated with new lighting either, which tends to be very heavy in the blue components. Lots of research links usage of blue-heavy white lighting to damaging circadian rhythms, which can lead to significant health effects. https://www.sciencedaily.com/releases/2011/09/110912092554.h...
This is not exactly what we are talking about. Yes artificial blue light disrupt our natural sleep rhythm. Yes there is research that shows this fact. But, that does not mean that we are not effected by the sun.
This research would need to show that blinds and artificial blue light would be sufficient to replace natural sunlight for setting the sleep rhythm to a healthy level. The existence of flux actually suggests the opposite is true, and people need software to prevent artificial blue light from disrupting the sleep rhythm.
"But ophthalmologists aren’t worried. The blue light emanating from the sun drastically overpowers any rays coming from your screen. And so far, all of the research on how real human eyes react to blue light has failed to link screens to permanent damage of any kind. Blue light’s most concerning effects still seems limited to sleeplessness."
We can only hope that control of blue light emissions will be natively implemented by all phone and tablet manufacturers, to protect the future health of billions of humans. Here are some articles about the impact of blue light on eyes and sleep.
http://thenextweb.com/lifehacks/2014/04/23/7-things-can-righ..., "Blue light is able to pass through what is called the retinohypothalamic tract, or pathway. This pathway is responsible for regulating our circadian rhythm and a number of other biological and behavioral processes."
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831986/, "Hastings and Sweeney’s paper, published in the December 1958 Biological Bulletin, gathered dust for decades. No one thought these findings might hold any relevance for humans, whose circadian rhythms were then widely believed to be relatively insensitive to light. But scientific discoveries in the past two decades have changed all that."
https://theconversation.com/a-dark-night-is-good-for-your-he..., "In the last decade or two it has become clear that the genes which control the endogenous circadian rhythm (the “clock genes”) also control a large part of our entire genome including genes for metabolism (how we process the food we eat), DNA damage response (how we are protected from toxic chemicals and radiation), and cell cycle regulation and hormone production (how our cells and tissues grow)."
There is room lighting with low-blue content, e.g. the G.E. Align PM bulb, http://www.amazon.com/gp/product/B00PLR3M0M & https://gigaom.com/2014/09/01/what-is-the-blue-light-from-ou..., "It remains unclear whether our screens themselves will soon emit less blue light — Hansler is pessimistic because he says that changing the amount of blue light will be like admitting that the screens are causing health problems, and lawsuits could ensue."
> Blue LED light may be toxic to your retina with long term exposure.
I wasn't aware of this. Do you mean LED light specifically? Is it in some way inherently different from the much more intense blue light of the sun? I don't see how light from one source can be any more damaging than from another source; it's all just the same EM radiation.
I'm not sure why people are downvoting you. It's a documented fact that blue light from the screens of electronic devices inhibits melatonin production.
The evidence that blue light is bad for sleep is much worse from an experimental standpoint than the evidence that it improves cognition and reaction time, which are obviously rather important considerations in street lights. Consider for instance that placebo glasses which filter the so-called harmful blue light wavelengths have been shown to fully reverse the apparent effect on sleep quality. This is despite them just being clear glass with no appreciable filter effect on visible light.
It is literally true that human mind is suggestible to an unimaginable degree.
If you look at the progression of artificial lighting, from candles, to incandescent, to halogen incandescent, to fluorescent, to LED, each generation typically increases both the blue light production and the brightness. Such strongly blue spectrum isn't an essential feature of the technology, so I suspect that it's marketing driven because it looks more futuristic.
Additionally, a lot of LED lighting flickers at frequencies that are visible when you move your eyes via the phantom array effect:
https://en.wikipedia.org/wiki/Flicker_fusion_threshold#Visua...
I personally find this very annoying, but even if you don't consciously notice this it's something not found in nature, and I'm not aware of any long term safety studies.
I'm very skeptical of these changes. Humans have a poor track record of predicting safety implications of new technology (eg. radioactive materials as health products, leaded gasoline, etc).
Is the screen time thing about blue light? I mean I sleep way better and feel way better when I am camping away from artificial lights. In that respect I think artificial lighting causes depression and lack of sleep.
And because (a) blue light causes your eyes to become bright-adapted, ruining your night vision, (b) blue light is incredibly distracting in your peripheral vision causing massively more glare than "warmer" light sources, (c) blue light screws up circadian rhythms for people and wildlife.
Light brightness and spectrum are associated with retinal damage. Blue light from LED overexposure can certainly do harm and can also affect your sleep cycle and hormone balance. I would not bake my eyes with these things anytime soon.
sigh Fine, here are more articles. If you don't want to believe in peer-reviewed academic literature, I'm not sure why I'm bothering. Statistically significant results can be obtained with few participants. Behold the power of math.
Nocturnal light exposure impairs affective responses in a wavelength-dependent manner.
>Our results demonstrate that exposure to LAN influences behavior and neuronal plasticity and that this effect is likely mediated by ipRGCs. Modern sources of LAN that contain blue wavelengths may be particularly disruptive to the circadian system, potentially contributing to altered mood regulation.
Out of the lab and into the bathroom: evening short-term exposure to conventional light suppresses melatonin and increases alertness perception.
>Subjective alertness was significantly increased after exposure to three of the lighting conditions which included blue spectral components in their spectra. Evening exposure to conventional lamps in an everyday setting influences melatonin excretion and alertness perception within 30 min.
Non-visual effects of light on melatonin, alertness and cognitive performance: can blue-enriched light keep us alert?
Exposure to light at 6500K induced greater melatonin suppression, together with enhanced subjective alertness, well-being and visual comfort. With respect to cognitive performance, light at 6500K led to significantly faster reaction times in tasks associated with sustained attention (Psychomotor Vigilance and GO/NOGO Task), but not in tasks associated with executive function (Paced Visual Serial Addition Task).
[...]
Our findings suggest that the sensitivity of the human alerting and cognitive response to polychromatic light at levels as low as 40 lux, is blue-shifted relative to the three-cone visual photopic system. Thus, the selection of commercially available compact fluorescent lights with different colour temperatures significantly impacts on circadian physiology and cognitive performance at home and in the workplace.
Evening use of LED screens alters circadian rhythms and has a detrimental effect on cognitive performance: https://www.physiology.org/doi/full/10.1152/japplphysiol.001...
You can find more. Wikipedia has 40 citations here https://en.wikipedia.org/wiki/Effects_of_blue_light_technolo...
Your counterpoint is irrelevant. Non-artificiality isn't a guarantee of benefit: if you go outside in the daytime and look at the sun you'll go blind.
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