Blue light technology is easily becoming one of the most common forms of light exposure to the human eye. In an age of tablets, iPads, and every kind of digital screen imaginable – the direct exposure of blue light is almost unavoidable. Blue light is by no means as harmful as ultra-violet rays. It comes directly from the sun, and exposure to it to a certain degree is perfectly normal. However, unlike our body’s ready defenses against UV, there is no defense against blue light. So, what are the harmful effects of blue light?
1. Sleep Cycle and Circadian Rhythms
A certain amount of exposure to blue light has been shown to have a positive effect on one’s body clock. The very basis of light therapy, exposure to natural forms of blue light (such as the one emitted from sunlight) can have extremely positive effects on one’s body clock, improving sleep. However, there is a dark side. Excessive exposure to blue light can actually counteract this process. Exposure to blue light at night can actually suppress the production of melatonin (the natural hormone that causes sleepiness). This leads to a negative effect one one’s circadian rhythm, and causes sleeplessness.
Immediate exposure can cause sore or irritated eyes, difficulty focusing and trouble sleeping while continued exposure could lead to damaged retinal cells over time which can cause serious vision problems such as age-related macular degeneration.
2. Macular Degeneration
Macular degeneration is a condition in which the central part of the retina (the macula) becomes damaged, leading to blurry vision and eventual vision loss. While it is a naturally occurring process for many people above the age of 60, exposure to blue light from a young age can actually increase the risk of MD. This is because the eye has no natural protection against the blue light emitted from devices. The direct contact of the light and the retina can cause MD.
3. Eye Strain and Dry Eyes
Along the lines of other eye-related damage, blue light exposure can cause a massive strain on the optic muscles. Continuous staring at a digital screen causes the eye muscles to constantly remain in a tightened state of focus, leading to excessive strain. This can cause not only headaches, but also cause eyes to become dry and painful. It can even go as far as causing neck and shoulder pain, difficulty concentrating, blurred vision, and excessive sensitivity to natural light.
4. Cancer, Blood Pressure and Obesity
A recent study by Harvard has linked blue light exposure to medical conditions such as types of cancer (particularly breast and prostate), diabetes, heart disease, obesity, and increased risk of depression. Although there has been difficulty in pinpointing the exact correlation, there is a link between the hours of exposure to blue light and these diseases. A highly possible inference to draw is the decrease of melatonin caused by blue light, and the hormonal changes to the circadian rhythm, can have a domino effect on health.
5.Eye Damage and Near-Sightedness
Studies have also shown that use of digital screens – particularly amongst children – can cause near-sightedness. This is not only due to increased digital eye strain but also due to the chemical shift in the eyes from exposure to blue light. The photoreceptor cells that blue light damages are not the kind of cells that can regenerate themselves. This leads to an irreversible level of damage.
The fact remains that blue light is both a boon and a bane to the new age. While its positive effects have made incredible headway in therapy (particularly for mental health), like all good things, too much of it is bad. Companies that create products emitting blue light are well aware of these negative effects and are attempting to fix the problem by increasing awareness and introducing new counter-effective changes to their products.
For instance, most phones and laptops have introduced a “night mode” feature that allows devices to switch from blue light to red light (the least harmful wavelength) after a certain time of night. Therapists and wellness experts are suggesting new ways to introduce relaxation periods between screen times (which can also now be monitored). Night light experts are switching to red LEDs instead of blue ones. Companies are creating protective eyewear and glasses against blue light. The bottom line is that taking the right precautions is key to protecting yourself against blue light damage.