コンテンツへスキップ

【Caution!】The Effect of Violet Light


Spread the love

Myopia(Nearsightedness) Control Study

Myopia tends to be increasing worldwide.

According to Brien Holden VISION INSTITUTE referring to a study published in the journal Ophthalmology

“Half the world’s population (nearly 5 billion) will be short-sighted (myopic) by 2050, with up to one-fifth of them (1 billion) at a significantly increased risk of blindness if current trends continue”

A study by the team of the Opthalmology Department of Keio University school of Medicine in Japan announced that Violet Lights may have the effect of suppressing myopia progression(myopia control).

If you are not aware of this study’s results, you need to be careful!

Only being known the result can be danger.

Here is why, so you can be aware.


Suponsered Link


What Is Myopia, Nearsighted Or Shortsighted
Focus And Retina

What is myopia?(meaning or easy definition)

As you may know, myopia is known commonly as “nearsightedness” or “shortsightedness,” which is one of the conditions generally considered among refractive errors.

Normally, the light comes into your eyeball and the focus reach to retina, and then you can see what you want to see without blurred vision.

Proper focusing of the retina is crucial.

If you have myopia, the focus in your eyeball doesn’t reach to retina due to the extension of the depth of the eyeball, and that’s why when you see into distances, you have poor vision.

Imagine a magnifying glass.

Focusing on a paper can cause fire to break out.

That shows how much energy is contained in focusing.

Focusing at the retina creates the full energy to see clearly.

You Need To Know

Definition Of Ultraviolet

What is ultraviolet light(or rays)?

Ultraviolet light(rays) is a type of electromagnetic radiation which comes from the sun and is transmitted in waves or particles at different wavelengths and frequencies.

Let’s see the definition of ultraviolet which is concluded by CIE( Comision Internationale de I’Elairage: International Commission of Illumination).

UVC:100〜280nm
UVB:280〜315nm
UVA: 315〜400nm

Although internationally this broad range is defined, some people use a different broad range, especially UVA.

This broad range is called invisible light.

How the study went?
Miopia Suppression

Study on Chicks

In short, according to research,
 multiple studies had shown outdoor activities could lead to the suppression of myopia progression, though animal studies and epidemiological studies, however nobody identifies what leads to suppressing myopia.

They focused on violet light, much of which is included outdoors.

The results show they conducted on 4 types of chicks’ eyes, which induced myopia by covering with plastic goggles were exposed by violet light (average of myopia progression was to around -5D) which induced myopia by covering with plastic goggles weren’t exposed by violet light (average of myopia progression was to around -15D)
which didn’t induce myopia were exposed by violet light. (Average was no myopia progression) which didn’t induce myopia weren’t exposed by violet light. (to around -1D)


*(Fig.1) The vertical axis indicates diopter and the horizontal axis showed 4types of chicks eyes, two of which on right showed “induced myopia” and the other two on left showed “didn’t induce myopia”. VL means Violet Light.
the Opthalmology Department of Keio University school of Medicine

They concluded violet light increase the expression of a gene known as EGR1(Early Growth Response 1), which is responsible for preventing myopia in chicks.

And I agree this result can be preventing myopia progression in chicks, but you need to listen carefully because 360〜400nm wavelength of violet light which they call is actually same as we call it UVA broad range.

Violet Lght Exposure And Children Wore Contact Lenses

Clinical trial for humans wore contact lenses

Secondly, as clinical trials, they compared different types of contact lenses that were worn by nearsighted children from age 13 to 18.

They were further divided into two groups; children who wore violet light transmitting (VL-T) contact lens (116 people 116 eyes) and children who wore violet light blocked (VL-B) contact lens (31people 31eyes).

The result revealed there is a significant difference between VL-T lens and VL-B lens.

How different?

The result showed how different axial lengths were, in spite of the fact that they showed its diopter in the chick’s case.

You know why?

Because the differences are too small to show its diopter.


*(Fig.2)The vertical axis indicates axial length(mm) after a year and the horizontal axis shows about Violet Light exposure.
the Opthalmology Department of Keio University school of Medicine

The researchers revealed the result of comparing two groups one year later, and there was a significant difference in their axial lengths and VL-T is only 0.05mm shorter than VL-B.

Although that’s a significant difference, converted 0.05mm of axial length into diopter, which means the differences are only about 0.17 diopter.

If you’re told about your contact lens by your eye doctor “the degree of the lens will be increased by just one phase”, the degree of the lens will be increased - 0.25 diopter.

In a nutshell although children in two groups may increase their myopia one year later, same range of the degree will be increased.

Do you think violet light exposure can be effective in suppressing your myopia progression?

Are you wearing glasses or sun-glasses for UV protection?

If you wear glasses or sun-glasses, the lens can be UV380 or UV400.

That means you can protect your eye from UV and it can be blocked wavelength up to 380nm or 400nm.

Using these items have already been led to blocking VL.

If Violet Light can be truly environmental factor of suppressing your myopia progression, you will need to give up UV protection.


Suponsered Link



Spread the love