On a day to day basis, we are exposed to a wide range of light rays. We wake up to put on the lights, we spend time glued to the tv or our PCs, let’s not even get into how much we use our smartphones. We hardly stop to question the effect of all these exposures. Well, the kind of light we are exposed to can have several effects depending on its wavelength. White light consists of a spectrum of lights rays. The novel way to see the different shades involves the use of a glass prism which usually separates sunlight into light rays ranging from red to violet, this being based on their wavelengths. In this particular article, focus has been put on blue light, just to highlight some of its detrimental effects and how you can be out of harm’s way.
What is blue light?
As alluded to earlier, blue light is among the colors that are contained in the white light. Before we get into the finer details, it is good to appreciate that the wavelength of the various lights will determine the energy contained in them, and it is usually an inverse relationship; the lower the wavelength the higher energy and vice versa. The red light on one end usually has the longest wavelength and it has the least energy while the blue to violet lights have shorter wavelengths and more energy. Blue light usually consists of light rays with wavelengths ranging from 350 to 500 nm, in the middle of the spectrum. This has also been referred to as blue-violet when combined with violet light rays from the end of the spectrum. Besides what we perceive as white light, we also have invisible light rays. The infrared light rays consist of the electromagnetic waves just before the red light on the spectrum. Infrared light is usually employed in heat lamps or warming lamps. On the other end, we have ultraviolet rays, which could be quite toxic to the skin.
Sources of Blue Light
Before we delve into the important facts that you need to know about blue light, it is good to consider the various sources of blue light that you might be exposed to. Here is a list of the key sources:
- The sun
- Digital screens; computers, TVs, smartphones as well as tablets
- Electronic devices
- Fluorescent bulbs
- LED lighting
Notable Facts about Blue Light Rays & Its Detrimental Effects on our Health
- It is The Reason why the Sky Appears Blue
A blue sky is so because of the blue light rays. The reason behind this is the nature of the wavelength of blue light rays. Blue light rays consist of shorter wavelengths making them easier to be scattered upon striking either air or water molecules. Since they are scattered to a higher degree compared to the other light rays the sky dominantly appears blue on a cloudless day.
- Our eyes are susceptible to the effects of Blue Light
The structures meant to protect our eyes from the effects of blue light cannot block blue light rays. On the other hand, the anterior structures of our eyes; the cornea and the eye lens can be able to about block 99% of UV light. This implies that the retina which is quite sensitive to light can be protected from the adverse effects of UV light rays. Since close to 1% of UV light gets to the retina it is recommended that you use sunglasses with the capability of blocking 100% of UV light rays. These light rays have been associated with cataracts, pterygium, snow blindness and even cancer due to the damage they cause to the eye structures. The macula, a highly light-sensitive area in the retina concerned with optimum vision, can degenerate due to the prolonged exposure to blue light. Macular degeneration could lead to permanent loss of vision. It is yet to be determined what extent of exposure to blue light from digital devices and electronics could lead to macular degeneration. It’s advisable that you reduce the amount of exposure or you make use of protective sunglasses.
- Exposure to blue light leads to digital eye strain
As mentioned earlier, blue light has shorter wavelengths and thus it is easily scattered. Since digital devices usually emit blue light, your vision might be scattered while using these devices. This leads to a reduction in the level of contrast and this could lead to digital eye strain, straining of the eyes while using digital devices. Digital eye strain is also referred to as digital strain syndrome. To counter this use of yellow tinted glasses has been backed by research in reducing our exposure to blue light rays of wavelengths less than 450 nm. You can thus use this kind of sunglasses to increase your comfort while using digital devices.
- Your risk of exposure to blue light significantly increases after cataract surgery
In the event that you need to undergo cataract surgery, there is an association between our natural lens and a reduction in the exposure to blue light that you need to consider. As our natural lens ages, our exposure to the shorter wavelengths of blue light significantly reduces. This is an add on to the health of our eyes due to the relative reduction in exposure to blue light. During the cataract surgery, our natural lenses are usually replaced with artificial ones. This would lead to increased exposure to blue light which might further damage the ailing eye, certainly when the intraocular lens does have blue light filters. With this in mind, it is prudent to mention this before cataract surgery to create room for the incorporation of blue light filters. This could be accomplished with the use of special intraocular lenses or alternatively the use of special eye sunglasses.
- Exposure to blue light at night could lead to several cancers
Some researchers from Harvard have shown that exposure to blue light at night could lead to the development of several cancers; prostate and breast cancer in particular. Apart from this some lifestyle diseases such as Diabetes, increased risk of depression, Heart disease as well as obesity could be significantly increased with exposure to blue light at night. This association has mainly been attributed to the lower levels of melatonin. Blue light rays usually suppress the secretion of this hormone and it could explain why all these conditions result.
Some Benefits of Blue Light Rays
Away from the numerous negative effects, blue light rays are also useful in our daily lives. Some of the notable benefits include:
- You need to appreciate blue light rays as far as alertness, memory, as well as cognitive functions, are concerned. This because of the effect of HEV, high energy visible light on the mind. Besides this, blue light usually elevates our moods.
- The seasonal affective disorder is usually treated using light which mostly consists of blue light. This is usually referred to as light therapy. This disorder usually sets in during the fall as well as the winter seasons. The light used in this mode of treatment is hugely made up of HEV blue light.
- The circadian rhythm is usually controlled by exposure to blue light. This usually controls the sleep cycle as well as our body’s natural wakefulness. Daytime exposure to blue light really aids in maintaining this circadian rhythm. Increased blue light exposure at night could, however, disrupt this rhythm causing not only daytime fatigue but also sleepless at night.
What About UV light…
Invisible light rays with a wavelength shorter than that violet light rays usually make up the ultraviolet light. As such they have higher energy. This increased energy could be beneficial but increased exposure leads to detrimental effects on our skin. Naturally, our skin usually utilizes UV light rays to make Vitamin D in adequate amounts. Besides this, less and controlled exposure to UV light could help in skin tanning and this has been utilized in skin tanning booths. Uncontrolled exposure to UV light has been associated with painful sunburns. Skin cancer has also been linked to increased and uncontrolled exposure to UV light rays. Snow blindness or photokeratitis has also been associated with excessive exposure to blue light rays.
How Do You Reduce Exposure to Blue Light Rays?
Having looked at some of the adverse effects of exposure to blue light, especially so exposure to unnatural sources of blue light, you need to reduce your exposure to the HEV. Here are ways in which you could go about this:
- The use of Blue Light Filters
If you happen to be tech-savvy with lots of your time being spent on digital devices, it is recommended that you consider using blue light filters. You could find blue light filters for your various devices ranging from tablets, PCs to smartphones. These filters usually work with little effect on the display from the screens. What is more, is that filters could also reduce the chances of your screens getting scratches. There exist several models in the market that you could try out, consult your optician for an appropriate blue light filter.
- The use of computer glasses
Computer glasses are a plus as far as reducing your exposure to blue light is concerned. Blue light glasses have blue blocking lenses reduce blue light.You could use blue light blocking glasses when operating your PC or other digital devices. One doesn’t need to have a prescription for these glasses provided you don’t have an underlying eye problem that demands the correction of your vision. This has immensely increased their availability for use. You can additionally use them if you use contact lenses to correct your vision. What is more, is that you can use computer glasses to maximize your vision when using your devices. Individuals who have presbyopia could make use of these glasses accompanied by single vision lenses. This has the additional advantage of increasing the field of view in a clearer fashion. You need to remember that the digital devices should be at an arm’s length for this to work.
- Use anti-reflective coatings
This is a new kid on the block and it’s special in reducing the glare. They can afford protection from both the natural and artificial sources of blue light. However, while at it, spare some time for the beneficial effects of natural blue light.
- Try out Photochromic Lenses
Quite fancy in nature, these are able to keep you out of harm’s way as far as UV light and blue light are concerned. The beauty of photochromic lenses is their ability to darken automatically with exposure to outdoor UV rays.
There is so much to say about blue light rays or heavy energy visible light. It is of a shorter wavelength and despite the natural blue light having notable benefits to our health, excessive exposure to its artificial form has been associated with a number of detrimental effects. Not only does it disturb the circadian rhythm, it has also been associated with macular degeneration, causation of cataracts, pterygium, cancer of the eye and several health disorders such as diabetes, heart disease, and obesity. You can take actions by reducing exposure to blue light through the various means outlined in the article. The health of our eyes is key and we need to reduce exposure to blue light, especially from artificial sources.
Scientific Sources and Medical References:
Effects of blue light technology-Wiki
Blue light: It’s both bad and good for you-allaboutvision
Blue light has a dark side-Harvard Health Letter