There has been a lot of research and articles lately on how ultraviolet and blue light can permanently damage your eyes. Dr. Craig Sultan, owner of Eyeworks Optometry in Napa, CA, has written a great article on this subject. With Dr. Sultan’s permission I have included it in this week’s blog.

Ultraviolet and Blue Light Can Permanently Damage Your Eyes

At Moody Eyes we recommend blue light protection for our patients who spend much of their time on a digital device. These days that seems like everyone. Ask us about Retina Shield, an in expensive and effective way to protect your eyes. We also recommend quality prescription sunglasses that protect our eyes from the UV light. They also reduce glare and make it easier to see in bright sunlight.

Here is Dr. Sultan’s article…

Ultraviolet and Blue Light

Sunlight contains UV and blue light. UV light is part of the non-visible light spectrum and we are exposed to it every day when we’re out in the sun. It can cause damage to our eyes, particularly the cornea and the lens.

TOO MUCH UV light affects the front of the eye (cataract formation), while TOO MUCH blue light causes damage to the back of the eye (risk of age-related macular degeneration – AMD).


The cumulative effect of UV exposure can contribute to cataracts and other eye diseases.

UV light can cause sunburn and destruction of vitamin A. In more chronic forms, it can lead to skin wrinkling and damage to DNA, which can lead to melanomas and other skin disease. So exposure to UVB is cumulative to both the body and the eyes.

Just as UV light is dangerous to our skin, it’s also dangerous to our eyes. So it’s important that we protect them from UV damage.


Not all blue light is bad. Blue light can have healthy affects on vision as well as the body, and it is blue-turquoise light that tends to have beneficial effects.

Inadequate light exposure means inadequate blue-turquoise light, which can throw off our sleep/wake cycle. So this blue-turquoise light really plays a vital role in the general health of the individual.

There’s an increase in the use of digital devices and LED lights and compact fluorescent lamps which emit a high levels of blue light.

Blue light reaches deeper into the eye and its cumulative effect can cause damage to the retina. Furthermore, in certain wavelengths, blue light is implicated in the development of age-related macular degeneration (AMD).

By 2020, 90% of our light sources is estimated to be LED lighting. So our exposure to blue light is only increasing.

This underscores the need for us to protect our eyes from the harmful bands of blue-violet light.

Who most needs protection?

Those who have high exposure to white LED or fluorescent light bulbs in offices and homes, frequent users of LED computer monitors, tablets or smart phones.

Many companies are working on technology to look at harmful blue light and ways to block that and still allow healthy blue light to remain.

What Is Blue Light?

Visible light is much more complex than you might think.

Stepping outdoors into sunlight; flipping on a wall switch indoors; turning on your computer, phone or other digital device — all of these things result in your eyes being exposed to a variety of visible (and sometimes invisible) light rays that can have a range of effects.

Most people are aware that sunlight contains visible light rays and also invisible ultra violet rays that can tan or burn the skin. But what many don’t know is that the visible light emitted by the sun comprises a range of different-colored light rays that contain different amounts of energy.

Rays on the red end of the visible light spectrum have longer wavelengths and, therefore, less energy. Rays on the blue end of the spectrum have shorter wavelengths and more energy.
On one end of the visible light spectrum, blue light rays with the shortest wavelengths and highest energy, are sometimes called blue-violet or violet light. This is why the invisible electromagnetic rays just beyond the visible light spectrum are called ultraviolet (UV) radiation.

The Perils And Benefits Of UV

UV rays have higher energy than visible light rays, which makes them capable of producing changes in the skin that create a suntan. In fact, the bulbs in tanning booths emit a controlled amount of UV radiation specifically for this reason.

But too much exposure to UV causes painful sunburn — and even worse, can lead to skin cancer. These rays also can cause sunburned eyes — a condition called photokeratitis or snow blindness.

But ultraviolet radiation, in moderation, also has beneficial effects, such as helping the body manufacture adequate amounts of vitamin D.

Key Points About Blue Light

Blue light is everywhere.
Sunlight is the main source of blue light, and being outdoors during daylight is where most of us get most of our exposure to it.

The display screens of computers, electronic notebooks, smartphones and other digital devices emit significant amounts of blue light. The amount of HEV light these devices emit is only a fraction of that emitted by the sun. But the amount of time people spend using these devices and the proximity of these screens to the user’s face have many eye doctors are concerned about possible long-term effects of blue light on eye health.


Apple Released Blue Light Filter In iOS Update For iPhones And iPads

Blue light exposure may increase the risk of macular degeneration.

The fact that blue light penetrates all the way to the retina (the inner lining of the back of the eye) is important, because laboratory studies have shown that too much exposure to blue light can damage light-sensitive cells in the retina. This causes changes that resemble those of macular degeneration which can lead to permanent vision loss.

Although more research is needed to determine how much natural and man-made blue light is “too much blue light” for the retina, many eye care providers are concerned that the added blue light exposure from computer screens, smartphones and other digital devices might increase a person’s risk of macular degeneration later in life.

Blue light contributes to digital eye strain.

Because short-wavelength, high energy blue light scatters more easily than other visible light, it is not as easily focused. When you’re looking at computer screens and other digital devices that emit significant amounts of blue light, this unfocused visual “noise” reduces contrast and can contribute to digital eye strain.

Research has shown that computer glasses with yellow-tinted lenses may increase comfort when you’re viewing digital devices for extended periods of time.

Click here for more from Dr. Craig Sultan and Eyeworks Optometry