Do We Need Blue-Light Filtering Lenses?

By Dr Suklengmung Buragohain

Date: 17/05/2022

We have come across many advertisements for blue light filtering lenses for spectacles on television, in spectacle shops or outside eye clinics. On the internet as well you can observe that as soon as you insert the words “Blue light filtering lenses” into the google search engine an extensive list drops down in front of you telling you why you should be getting those lenses and why blue light is harmful to you. If big spectacle companies claim such a thing then that must be true right? Or is it? Let us review what science tells us. 

Google search results for blue light filtering lenses

Background


The wavelength of light that humans can perceive ranges from 380 to 700 nanometers (nm) and blue light falls within this range with a wavelength of 450nm. It has been observed that digital devices such as smartphones and computers with backlit LED displays seem to emit a higher level of short-wavelength visible light (such as blue light) than traditional sources of light.1,2 


Is Blue Light Harmful For The Eye?


With the increasing use of digital devices, an extensive number of people have reported having complaints such as sore eyes, eye fatigue, headaches, blurred vision, and dry eye.3 Such symptoms have been classified collectively as “Computer Vision Syndrome” or CVS in scientific literature. Having said this, it is however not clear whether blue light plays any role in developing CVS as the nature of CVS is multifactorial (binocular vision disorders, uncorrected refractive error or presbyopia, and tear film dysfunction). 4 Two randomized control trials that compared blue filtering lenses and normal lenses found that blue filtering lenses do not provide any relief from digital eye strain. 5,6 In simple terms, the usage of digital devices can cause symptoms of CVS but there is no scientific evidence that those symptoms are due to blue light emitting from the screens. 


There are also reports of deleterious effects of blue light on the sleep cycle. There have been studies conducted that report that there is an association between evening use of electronic devices and adverse sleep quality, altered circadian timing and reduced daytime alertness.7,8 This is of concern as there is evidence that suggests that disruptions to biological cycles and the circadian rhythm can have potentially adverse effects on a diverse range of health parameters. 9 Thus, sleep and related conditions can be affected by blue light. 


Many advertising agencies claim that blue light filtering lenses help in preventing damage to the retina (which is responsible for vision) of the eye. A few animal studies show that blue light can cause retinal damage, but there is no such evidence of something similar happening in humans yet. 10,11 So with the scientific evidence that we have at present, we cannot claim that blue light is injurious to the human retina. 


Why Is This Topic Important?


Many companies have been pitching the idea that blue light causes substantial damage to the retina along with symptoms of CVS and have been selling blue light filtering lenses as a means of protecting the eyes from it. This claim however doesn’t seem to have any scientific backing (at least at present), and it is important that an average customer knows this fact. In 2015, the UK Advertising Standards Authority (ASA) found that a retailer was putting misleading claims that blue light causes retinal damage and was subsequently fined. 12 

Misleading Claims From A Popular Spectacle Website

How To Reduce Eye Strain Due to Use Of Digital Screens?


There are a few simple habits that we can adopt in our daily work while working with digital screens to reduce eye strain. These methods are recommended by the American Association of Ophthalmology (AAO) and are given below:



Conclusion


There is at present no clinical evidence that blue light emitted from digital screens is harmful to your eyes. There is also no evidence that blue light filtering lenses can prevent symptoms of eye strain due to screen time. 


References