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Is blue light bad?

People continually ask me if the blue light emitted from all modern-day LED devices is harmful to their eyes. It is no wonder there is total confusion with so much miss-information. Mainly from companies and people trying to sell you blue light blocking products or medicines. Even amongst optometrists there is also a lot of debate about blue light. But what I am going to tell you is what is known. Is blue light bad?

Firstly, what is blue light

Blue light is classed as the wavelengths of light between 420–500nm (nano-meters). This is within the visible spectrum.

visible light spectrum
visible light spectrum

We know that the sun emits 100 times more blue light when compared to all consumer LED device. We also know that the blue light from the sun is extremely beneficial in setting our circadian rhythm or body clock. Our circadian rhythm affects our sleep, blood pressure and heart rate, hormone secretion, and more. Blue light also naturally suppresses the body’s melatonin production. Which does boost our alertness and attention. Evidence is now associating circadian rhythms with eye growth and refractive error development. So it is imperative not to upset your natural body clock.

Is blue light bad?

The trouble with blue light from LED devices

Some researchers have shown that blue light at 445nm when the energy is 3 μW (micro-watts) or greater can cause cell damage. But this research was done under laboratory conditions. Not on actual living tissue like an eye. And in a healthy human all living tissue is constantly repairing itself. Electronic devices typically emit no greater than 1 μW. Note, That from such low energies it has not been shown that there is any harm or accumulative effect.

Is blue light bad
Is blue light bad

So the real problem with LED devices is if they are used at night. As the blue light can upset your circadian rhythm or body clock. We know for example that night shift workers do not get enough blue light of a day time to set their circadian rhythm correctly. Therefore suffering from ill-health and a shorter life.

So what should you do about blue light

If you don’t spend much time out doors of a day. And you are stuck in front of an electronic device then the small amount of blue light being emitted may actually help to set your circadian rhythm.

But of a night-time I would recommend that you turn off your devices. Yes, I said turn off your devices. And for all of you who just said, “What, are you crazy?” And you cannot be without your device of a night. Then at least turn down the brightness of your display. Push the device further away from your face. And turn on a warm white light. This will then diffuse the blue light from your device so it will not upset your natural body clock. You could even wear blue block glasses but please only during night time hours.

Conclusion – Is blue light bad?

When received during daylight hours blue light has real known benefits. And preferable never received at night so you don’t upset your circadian rhythm.

I do not recommend wearing blue block sunglasses during day light hours. (Unless advised by an optometrist to do so). As you do require the suns blue light to set your circadian rhythm. So that you will have a normal healthy life.

Myths about blue light. – From those with no experience in optics. As seen on many websites.

  • Short-wavelength blue light is not as easily focused. As it’s focus point is in front of the retina. Wrong. All visible light does travel all the way to the retina. It does not stop just in front of the retina.

The reason for confusion on is blue light bad

Blue light receives such a bad reputation due to it’s incorrect classification by some countries in their sunglasses standard. Here in Australia ultraviolet or UV radiation is classified as all rays between 100nm and 400nm. Which is correct. These are known to be harmful to the skin and eyes. Both violet and then blue light start at 400nm and are within the safe visible spectrum.

But in both the USA and EU sunglasses standard they classify UV radiation from 100nm to 380nm. And this is incorrect. The spectrum of UV radiation between 380nm and 400nm was removed from both sunglasses standards. When they copied the Australian sunglasses standard with this one minor change. As they believe the sun in their countries is not as strong as it is in Australia. Which is true. However there is now this missing 20nm of harmful UV rays. This is then confused sometimes with High Energy Visible light (HEV – blue light). Because it is not correctly classified as harmful UV radiation.

The problem is children between the ages of 0 and 10 years old do transmit these harmful UV rays between 380nm and 400nm all the way to the retina. Therefore true 100% UV protection is a must for everyone but especially young children. You can follow this link to read all about how UV damages eyes.

What I have stated is based on information we have today and this may change as we gain more information in the future.

The real dangers are from UV radiation

Ultraviolet radiation is well-known to cause many eyes diseases and skin cancer. So protecting your eyes with good quality sunglasses is essential to prevent long-term exposure to UV rays. We know that even small amounts of UV rays over time do have an accumulative effect leading to eye diseases. Such as cataracts, pterygium, actinic & droplet keratites, pinguecula and macular degeneration.

If you are ready to buy the best baby or kids sunglasses that will truly save sight. Without a ridiculously high price, then take a look at our online shop.

Don’t miss the latest sunglasses “WARNINGS” on this page. They will save your child’s eyesight.

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