Light is a permanent fixture of our lives that comes from many artificial or natural sources. For 365 days in a year, light enables us to see, but it isn’t all good. Case in point, the detrimental effects of UV rays have been extensively documented over the years. But what about visible light? The visible spectrum of light is the one that allows our eyes to form images.
In this spectrum, the high energy and short wavelength blue light forms about one-third of all visible light. We are naturally exposed to blue light by the sun during the day while at night, fluorescent lighting, smartphones, laptops and other gadgets prevail. Blue light has since become a major cause for concern with people wondering whether blue light can damage eyes.
Blue light undeniably has both positive and negative effects on our body. It’s the part of the light that best enables us to see with high visual acuity, boosts alertness and helps regulate our sleep cycle. However, blue light in excess can be very harmful to many parts of the eye and seriously affect future visual capacity. Unfortunately, despite the fact that the eye is quite good at blocking UV light, that’s not the case with blue light.
Virtually all blue light passes through the eye unhindered and reaches the retina. This makes sense because the eye isn’t designed to completely block part of the very light that enables you to see. But this lack of hindrance means that blue light will cause insidious, cumulative and possibly permanent damage to your eyes if you do nothing about it. So, can blue light damage eyes? Yes, and here’s how.
Blue Light Can Damage the Photosensitive Cells of the Eye
Excessive exposure to blue light has been shown to damage the photosensitive cells of the eyes that include rods and cones. Studies done on mice have proved that cumulative exposure to blue light can damage the photoreceptors of the eye. It also causes accumulation of fluid in the retina as well as rupture and leaking of tiny blood vessels in the photoreceptor level of the macula. The final result is changes that resemble those seen in macular degeneration.
Macular degeneration is the leading cause of vision loss and it is caused by the deterioration of the central portion of the retina, the macula. This is the most light-sensitive part that’s responsible for focusing central vision in the eye. In this case, you’re left with permanently blurred vision as the best case scenario and permanent blindness as the most likely result.
Blue Light Causes Eyestrain
The high energy blue light waves have been heavily implicated in digital eye strain or computer eye strain. These High Energy Visible (HEV) or ‘blue’ light waves tend to scatter more in the eye. This scattering or flickering happens due to the fact that blue light waves are shorter and have more energy than their longer, weaker counterparts. Due to the flickering, there is a glare which diminishes your visual acuity and clarity. Eventually, you experience significant eyestrain that may be accompanied by headaches and mental fatigue. Eyestrain caused by blue light is mainly experienced by people who are constantly looking at a computer screen or any other device that emits blue light.
Blue Light Can Cause Eye Cancer
Another major reason to be wary of blue light is that it has been implicated in the formation of intraocular (uveal) cancers. HEV light has been proved to significantly increase the rate of cell division which is associated with the development and growth of cancer. In some animal studies, blue light has caused the development of uveal cancer in animals which had no previous evidence of cancer. In other models, an existing uveal cancer drastically increased its rate of cell proliferation in response to blue light. Blue light can damage eyes to the extent that it has the potential to cause cancer. It’s therefore a good idea to limit your exposure to it as much as possible.
Those Vulnerable to Eye Damage by Blue Light
Children under 9 years old are very susceptible to damage of the photoreceptor cells by blue light. This is because they possess very little protective macular pigment in their eyes that reduce the amount of light reaching the retina. Consequently, not even a little blue light is filtered out hence extensive damage may be done if their eyes experience over-exposure to blue light. You should, therefore, restrict the use of computers, phones and other handheld devices, especially in dim lighting in order to protect their eyes.
A protective pigment in the eye is melanin, which is brown. The amount of melanin pigment in the eye determines the colour of the eyes. Less melanin means that the eyes are more vulnerable to damage by blue light. For this reason, those with blue eyes are more susceptible to cataracts or macular damage since they have the least amount of melanin in their eyes. Green eyes have a larger amount of melanin and are less susceptible. Hazel and brown eyes show the least susceptibility.
From the above, it’s evident that blue light can cause a great deal of harm to your eyesight. But don’t fret, there are a number of ways you can safeguard your eyesight by filtering out blue light. You can check out our screen protectors, protective glasses and other products here at Ocushield to quickly get some protection for your eyes.