What Is Blue Light and How Do We Protect Ourselves From It?
Thu, April 22, 2021

What Is Blue Light and How Do We Protect Ourselves From It?



Retinal specialists who treat conditions that affect the retina are asked about the negative impacts of blue light-emitting devices each day, noted David Ramsey, MD, Ph.D., MPH of Harvard Health Publishing, a health and medical information website. In fact, many individuals wonder whether blue light increases their likelihood of blindness and age-related macular degeneration.


Concerns Surrounding the Use of Blue Light-Emitting Devices

Online market research website Ask Your Target Market (AYTM) and Eyesafe, a blue lights solutions technology, conducted a survey on June 18, 2020, finding that 69.33% of respondents were concerned about extended exposure to their devices and screentime (versus 30.67% of those who said “no”). 78.67% were also aware of the health and safety concerns that have been raised about screentime and extended exposure to blue light from devices (versus 21.33%).

65.33% of consumers experienced attribute eye irritation as a result of extended use of electronic devices followed by headaches (51.33%), sleep disruption (30%), dry eyes (29.33%), blurred vision (38%), shoulder/back pain (44%), and none of the above (17.33%). 9.33% said that productivity would increase by at least 50% if there was an effective protection against harmful blue light. Others said they might experience a productivity increase of at least 40% (8.67%), 30% (18%), 25% (14%), 20% (8.67%), 15% (7.33%), 10% (11.33%), and 5% (4.67%) when they are protected against blue light.

In a 2019 study by Asmaa Jniene of Hindawi, a commercial publisher of scientific, technical, and medical literature, 97.3% of young, male and female medical students used a blue light-emitting smart device at bedtime. Among those, 76.9% used them with the lights off in their bedrooms. The devices were used for leisure (75.9%) and reading (25.2%). Among those who perceived sleep disturbances due to using blue light-emitting devices at bedtime, 53.8% switched off the lights, 48.6% adjusted the brightness automatically or manually, and 11.9% put their smartphones and tablets under the pillow.

39.9% experienced sleep disruptions when checking messages, 41.6% had fatigue upon waking up more than once a week. 17.5% and 25.2% had headaches and irritability more than once a week, respectively. 56.3% said their smartphones or tablets are not switched off before heading to bed. The study showed a high prevalence of using blue light-emitting devices at bedtime, including unhealthy habits linked to poor sleep quality. According to the researchers, this affected the students’ daytime functioning.



The Definition of Blue Light

It is visible light with a wavelength between 400 and 450 nm (nanometers) that is perceived as blue by our eyes. It may be present even when you perceive light as white or another color. Common sources of blue light are CFL (compact fluorescent light) bulbs, LED lights, flat screen LED televisions, and devices like smartphones, explained Prevent Blindness, a site that focuses on preventing blindness and preserve one’s sense of sight.

Blue light from your devices will not increase your risk of macular degeneration or damage any part of your eye. Still, blue light is something to be concerned about as it has more energy per photon light than other colors in the visible spectrum— think green or red light. High doses of blue light can be damaging when it is absorbed by your body’s cells. Further, your blue light-emitting devices may disrupt your sleep and circadian rhythm. It can also cause digital eye strain. Symptoms of this condition are sore or irritated eyes and difficulty focusing. 

The effects of blue light are still being studied, so we have limited knowledge about it as of now, stated Fatoumata Yanoga. MD, of The Ohio State University Wexner Medical Center, a leader for healthcare and medical research in Ohio. Likewise, further studies need to be conducted to assess how much natural and manmade blue light is too much for the retina, as well as how much will contribute to eye diseases later in life. On the other hand, the benefits of blue light include boosting alertness and regulating your circadian rhythm. It can also aid in your memory and cognitive function and boost your mood.



Protecting Yourself Against Blue Light

At night, wear amber-tinted glasses to avoid exposing yourself to blue light. These glasses block all blue light. Hence, your brain will not be prompted to stay awake, said Kris Gunnars, BSc, of Healthline, a website dedicated to publishing content on medical information and health advice. A study by Kimberly Burkhart and James R. Phelps of PubMed, a research portal containing over 30 million citations for biomedical literature from MEDLINE, life science journals, and online books, found that shift workers wearing amber-tinted glasses before bedtime significantly improved their sleep.

While there are other studies that justify the use of amber-tinted glasses, one literature review by John G. Lawrenson, Christopher C. Hull, and Laura E. Downie of PubMed, has noted a lack of high quality evidence supporting the use of these glasses. You can also use anti-reflective lenses to reduce glare and increase contrast, advised Prevent Blindness.  Additionally, anti-reflective lenses can block blue light from the sun and devices. Speaking of which, consider using screen filters to minimize the amount of blue light emitted from your devices, which could reach your retina. It is also advisable to reduce the amount of time in front of your devices, if possible. Otherwise, take frequent breaks to give your eyes a quick rest. If your eyes feel dry, it is strongly recommended to use artificial tears.

Turn off all lights in your home one to two hears before heading to bed and opt to invest in a red or orange reading lamp, which will not emit blue light. Be sure that your bedroom is completely dark before you go to sleep or use a sleep mask. If you think your devices prevent you from falling asleep or disrupt your circadian rhythm, Ramsey suggested consulting your doctor to help limit device use at night. During the day, it is important to expose yourself to plenty of blue light. For example, you can go outside to get your daily dose of sunlight. If not, you can use a blue light therapy device, which is a lamp that simulates the sun, exposing your eyes and face to blue light.


Blue light can disrupt our sleep and cause eye strain. More studies need to be done on the effects of blue light on our bodies. Right now, the least people can do is to use amber-tinted glasses and if possible, limit screentime to reduce one’s exposure to blue light.