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LED: Blue LEDs Light Up Your Brain

It wasn’t long ago, relatively speaking, that humans woke and slept along with the rise and setting of the sun.

While the invention of modern artificial lighting has allowed us to be productive 24 hours a day, even in what would otherwise be the black of night, our bodies have not adapted to this onslaught of light when it should be dark.

Humans have long existed with the glow of firelight, and its corresponding yellow, orange and red wavelengths do not appear to have the detrimental effects (such as suppression of melatonin production) of other wavelengths of light, like white and blue.

Blue light, which is prevalent when the sun is bright and overhead, is particularly problematic. Photoreceptors, or light-sensitive cells, in your eyes track blue light, which in turn triggers different processes in your suprachiasmatic nucleus, a small region in your brain’s hypothalamus.

Among them is relaying to your pineal gland the news that when there is a lot of blue light, the production of melatonin should stop to facilitate wakefulness. As the sun sets and blue light decreases, production of melatonin increases, which helps you fall asleep.

The Introduction of Blue LED Lights

We’re in the midst of an unprecedented light experiment not only because of the widespread use of artificial light in general but also because over the past 20 years powerful blue LED (light-emitting diode) lights have been added to electronics like smartphones, computers and flat-screen TVs.

LED lights are rapidly replacing earlier lighting technology, including incandescent bulbs and compact fluorescent lamps (CFLs). There’s good reason for this, as LEDs are far more energy efficient, longer-lasting and produce excellent light quality compared to other types of lighting.

According to the U.S. Department of Energy (DOE), LED lights use at least 75 percent less energy, while lasting 25 times longer, than incandescent lighting.

It’s estimated that, compared to no LED use, widespread LED use in the U.S. by 2027 could save the equivalent electrical output of 44 large electric power plants each year, which would add up to a total of at least $30 billion in savings, according to DOE. LEDs are different from incandescent bulbs in three key ways:

  • They emit very little heat compared to incandescent bulbs and CFLs, which release 90 percent and 80 percent of their energy as heat, respectively
  • LEDs emit light in a specific direction, which makes them very efficient and reduces the need for reflectors and diffusers
  • LEDs contain a mix of red, green and blue light, which are usually combined to make white light; the light is brighter, whiter and bluer than incandescent bulbs, which contain far more yellow and red light
The “white” LED light is so bright and energy efficient that about 10 percent of U.S. municipalities are now using it for their streetlights, with more expected to follow suit. Unfortunately, in making these changes a new set of potential problems has emerged.

Blue LED-Lit Screens Confuse Your Brain

When your brain “sees” blue light at night, the mixed message can add up to serious health issues, and widespread ones at that, since a National Sleep Foundation (NSF) survey found that nearly everyone who responded used a television, computer, cell phone or other electronic device within one hour of going to bed at least a few nights each week.

In 2011, for instance, researchers found that evening exposure to LED-backlit computer screens affect circadian physiology. Among 13 young men, exposure to five hours of an LED-lit screen at night significantly suppressed melatonin production along with sleepiness.

Separate research revealed “blue light from light-emitting diodes elicits a dose-dependent suppression of melatonin in humans.”

Looking at a tablet for even two hours in the evening is enough to suppress your body’s natural nighttime rise of this hormone,8 while bumping it up to four hours leads to reduced feelings of sleepiness, increased time to fall asleep (by about 10 minutes) and lower quality sleep compared to those who read paper books for the same period.

Even driving home in an LED-lit area may throw your body clock off kilter. At the 2016 Annual Meeting of the American Medical Association (AMA), the AMA issued new guidance for communities on how to “reduce the harmful human and environmental effects of high-intensity [LED] street lighting.”

The AMA noted white LED lights “have a five times greater impact” on circadian sleep rhythms than conventional street lamps. This in turn, may lead to problems with sleep and related conditions.

AMA Board Member Dr. Maya A. Babu said in a news release, "Despite the energy efficiency benefits, some LED lights are harmful when used as street lighting.”10 She cited “recent large surveys” that found brighter nighttime light in communities is linked with:

Reduced sleep times
Dissatisfaction with sleep quality
Excessive sleepiness
Impaired daytime functioning

LED Lights May Harm Your Vision, Endocrine System and More

There are major downsides to LEDs that are not fully appreciated, even beyond their effects on sleep. 

LEDs have virtually no infrared and an excess of blue light that generates reactive oxygen species (ROS), which is why they’re so harmful for your eyes and overall health.

Other health problems rooted in mitochondrial dysfunction may also be exacerbated by LED lights, and these run the gamut from metabolic disorder to cancer. Wunsch explained:

"Blue has the highest energy in the visible part of the spectrum and produces, infuses, the production of ROS, of oxidative stress. The blue light causes ROS in your tissue, and this stress needs to be balanced with near-infrared that is not present in LEDs.

We need even more regeneration from blue light, but the regenerative part of the spectrum is not found in the blue, in the short wavelength, part. It's found in the long wavelength part, in the red and the near-infrared.

So tissue regeneration and tissue repair results from the wavelengths that are not present in an LED spectrum.

We have increased stress on the short wavelength part and we have reduced regeneration and repair on the long wavelength part. This is the primary problem … [W]e don't have this kind of light quality in nature. This has consequences. The stress has consequences in the retina; it has consequences in our endocrine system."

How to Make Digital Screens Healthier

When it comes to computer screens, Wunsch suggests reducing the correlated color temperature down to 2,700 K — even during the day, not just at night. Many use f.lux to do this, but I have a great surprise for you as I have found a FAR better alternative that was created by Daniel, a 22 year old Bulgarian programmer that Ben Greenfield introduced to me.

He is one of the rare people that already knew most of the information in this article. So he was using f.lux but was very frustrated with the controls. He attempted to contact them but they never got back to him. So he created a massively superior alternative called Iris. It is free, but you'll want to pay the $2 and reward Daniel with the donation. You can purchase the $2 Iris software here.OLED screen technology is another development that may be better than conventional screens.

"[With] the OLEDs technology, I'm not sure if the color is really stable in every angle you can look at the display," Wunsch says. "But definitely, if you have the screen technology where black is really black, then you have less radiation coming into your eyes and the OLEDs technology is able to provide this.

So the high contrasts between the black and white, all the black areas in the thin-film-transistor (TFT) screen or the standard screen are not really black. They are also emitting shortwave radiation. The OLED screen only emits where you see light, where there is black on the screen, there is no light. This might be preferable as long as you have no problems with the [viewing] angle."

To Protect Your Health and Vision, Stick to Incandescent Lights

LEDs are a perfect example of how we're sabotaging our health with otherwise useful technology. However, with knowledge, we can proactively prevent the harm from occurring. In summary, we really need to limit our exposure to blue light, both during the daytime and at night. So for nighttime use, swap out your LEDs for clear bulb incandescents, or low-voltage incandescent halogen lights that are run on DC power.

I also strongly recommend using blue-blocking glasses after sundown, even if you use incandescent light bulbs. Without these modifications, the excessive blue light from LEDs and electronic screens will trigger your body to overproduce ROS and decrease production of melatonin, both in your pineal gland and your retina, the latter of which will prevent repair and regeneration, thereby speeding up the degeneration of your eyesight.

"One thing to emphasize again, it's not the blue light coming from the sun itself which we should be concerned about. It's the blue light, the singular high energy visual light (HEV), which comes from cold energy-efficient non-thermal light sources. This is what causes the problem, not the blue light which comes together with longer wavelengths in a kind of natural cocktail that has the beneficial near-infrared spectrum …

The light surrogates from non-thermal light sources, these are [what cause] problems, and you have to be clever to avoid these Trojan horses. If you want to make it [safe], stay with the candles, stay with the incandescents," Wunsch says.

Source:, 12/01/16

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