Harmful Blue Light and Our Eyes

Most of us are very aware of the damaging nature of UV (ultra-violet) light. This damage involves both our skin and our eyes. Damage from exposure to UV light is cumulative over your lifetime,has been associated with increased risk of developing cataracts at a younger age1 and may be associated with a higher risk of developing macular degeneration (AMD).2 Damage from blue light, however, is something that is much lesser known.

Blue light exposure is also damaging to the retina.3 The amount of research into damaging blue light has increased significantly these last several years, and we now know more than ever before. Also, our exposure to blue light sources is increasing significantly in this age of technology. UV light exposure comes from the sun, so we are generally only exposed to this damage when we are outside. UV blocking sunglasses can protect us easily from UV damage to the eyes.

In contrast, most of our blue light exposure comes while we are indoors. Fluorescent lights, CFL light bulbs, LED light bulbs and screens; smart phones, computers, tablets and TV are the major sources of blue light exposure. These are things we are exposed to increasingly all the time. According to the Canadian Internet   Registration   Authority,   the average Canadian spends 45 hours per week on the internet.4

Recent studies have examined the effects of blue light more closely. One such study isolated individual wavelengths of the blue light spectrum and found that the 415 to 455nm range is the most damaging range of blue light to the retina.3 Other research has found a new receptor in our retinas that is most sensitive to blue-turquoise lights in the wavelengths of 480nm.5 These cells do not project to our visual areas of the brain; in fact, they project to the suprachiasmatic nucleus5 which controls our “biological clock.” This part of the blue light spectrum is very beneficial to the human body and helps control cognitive functions such as memory, alertness, circadian rhythms, mood and sleep.

Until recently, there have been few products available to help protect our eyes from harmful blue light. Now in 2013, we are seeing more and more products emerge. One limitation to protecting from blue light is that blue light is part of our visible light range. Blue light is a part of our vision, and if we filter out all blue light our colour vision and colour perception will be altered. So, this leaves us having to find a compromise: how much blue light can be filtered and leave colour vision unaffected?

One of the new products available is called Crizal® Prevencia by Essilor. This product is an upgrade to the standard Crizal® anti-reflection coating on your lenses. Crizal® Prevencia will block 20 per cent of the harmful blue light6 and allow the beneficial blue-turquoise light to pass through. This coating is applied on standard clear lenses and will not affect the patient’s colour vision. This coating is recommended for all patients who spend significant amounts of time being exposed to these blue light sources.

Stop in at our office at 500-4010 Pasqua St. to find out more and try this coating now. You can book an appointment by phone at 306.586.7036 or online at www.advanceeyecarecenter.com.

 

REFERENCES

  1. Hightower K. A review of the evidence that ultraviolet irradiation is a risk factor in Doc Ophthalmol. 1994-1995; 88(3-4):205-20.
  2. Li J. Are-Related Macular Degeneration, 2nd 2007; 66-67. Edited by Jennifer I. Li
  3. Paris Vision Institute. Photosensitized retinal pigmented epithelium cells exposed to blue
  4. Canadian Internet Registration http:// www.cira.ca/factbook/2013/canada-online.html.
  5. Gronifer The Good Blue and Chronobiology: Light and Non-Visual Functions. Points de Vue. 2013:68:19-22.
  6. Crizal Prevencia Product 2013.