Table of Contents
Light, also known as visible light, is electromagnetic radiation detected by the human eye. Electromagnetic radiation refers to the changes in electric and magnetic fields, leading to energy transportation at the speed of light.
Research shows that the speed of light is 300,000 kilometers per second through a vacuum. Visible light has different wavelengths and colors, such as red, orange, green, yellow, blue, indigo, and violet.
For instance, violet has the shortest wavelength, and red has the longest wavelength. Red has 700nm, and violet has 380nm wavelength on the visible light spectrum. Visible light exists in two forms: natural and artificial light. What’s the difference between these two lights, and how do they affect your health? Let us answer these questions!
Natural light produces color and heat from the radiation emitted by the sun. The earth’s atmosphere filters the natural light, allowing plants and other species to absorb it. Natural light offers a wide range of health benefits.
For instance, the sun is the biggest source of vitamin D. Vitamin D is an essential nutrient that regulates calcium and phosphorus absorption in your body, facilitating optimal immune system function.
Spending time in natural light allows your body to absorb an adequate amount of vitamin D, leading to normal bone growth and development. Vitamin D absorbed from natural light also improves resistance against several diseases. Health professionals suggest spending at least 20 minutes a day to absorb enough vitamin D from the natural sunlight.
On the other hand, vitamin D deficiency can cause severe health conditions, such as weak bones and muscles, osteoporosis, depression, and an increased risk of heart diseases. Sunburn is the most common adverse effect of natural light.
UV light causes sunburn due to direct sun exposure. Remember that UV light is a part of the invisible light spectrum and gets through your skin. Sunburn can damage and kill skin cells. It also increases the risk of skin cancer. Redness, bumps, and dry skin are common symptoms of absorbing too much natural light.
Artificial light sources include LED light bulbs, fluorescent lighting, computers, laptops, smartphones, tablets, and other digital devices. It has a lot more negative than positive for your health than natural sunlight.
Understanding when to expose yourself to artificial light can make you more alert in the daytime and help you fall asleep faster at night. Research shows that artificial light can cause negative effects on the entire ecosystem.
At the same time, it affects the human body, leading to eye damage, disrupted biological clock, depression, behavioral changes, and other health conditions. For example, your brain sends signals to your body to release melatonin, allowing you to sleep faster.
Remember, this process occurs when the sun goes down. Artificial light is everywhere, from LED, halogen light bulbs, to other electronic appliances or devices. The primary problem with artificial light is the harmful blue light.
Electromagnetic radiation comprises different bands along the spectrum based on the frequency of waves it emits. Microwaves, x-rays, radio waves, infrared, and ultraviolet are all bands of radiation that exist in different regions of the electromagnetic spectrum.
Humans can see radiation with wavelengths ranging between 380m and 760nm, known as the visible part of the spectrum or light. Bear in mind that scientists often apply the term light to infrared and ultraviolet bands.
Blue light is a component of the electromagnetic spectrum with shorter wavelengths and higher energy levels. Sun is the biggest source of blue light. However, blue light is also emitted from artificial sources, such as computer screens, laptops, LED TVs, smartphones, fluorescent light bulbs, etc.
Blue light emitted from digital devices can cause numerous health complications, taking a significant toll on your eyes and brain. Not only does blue light damage your eyes, but it also disrupts your circadian rhythm, leading to insomnia, an imbalanced sleep-wake cycle, and fatigue. As a result, you have an increased risk of other health conditions.
Unlike skin cells that regenerate every 4-5 days, your retinal cells exist in your eyes for life. Therefore, damage your retinal cells incur is permanent. The cornea and lens protect your retinal cells from harmful UV radiation because these structures can block UV wavelengths.
On the other hand, the cornea and lens can’t protect your retinal cells from blue light, leading to macular degeneration and cataracts. Blue light glasses can block these shorter wavelengths and prevent retinal damage.
Photochemical damage refers to damages caused by blue light to chemical structures inside your eyes. There are two types of photochemical damage: type-1 and type-2. The former is low intensity over a long period, and the latter is high intensity over a short period.
Type-1 photochemical damage occurs due to blue light emitted from your computer screen or smartphone. So, it imbalances the macular pigment in your eyes, leading to macular degeneration and other eye conditions.
Type-2 photochemical damage occurs when people look directly into the sun’s bright light or a car’s headlights at close range. It can cause immediate changes to the retinal cells, disrupting macular pigments.
Blue light glasses can block higher-energy light from penetrating your eyes and damaging the macula. These glasses have specialized lenses that filter harmful blue light, leading to improved eye health.
Reduced Visual Performance
Shorter wavelengths of visible light carry higher energy levels that scatter more due to bending properties when traveling through your eye’s optical layers. Research shows that increased scattering adds more noise to the image, causing fog-like or blurry vision.
The result of scattering means that blue light can cause glare and reduced contrast, making your vision uncomfortable and difficult. Blue light glasses enhance macular pigment levels in your eyes by reducing shorter wavelengths reaching the retina, leading to higher contrast sensitivity and enhanced glare disability.
Natural light and artificial light have their own pros and cons for human health and the environment. However, artificial light, including blue light emitted from digital devices, are more harmful to human eyes and brain than the natural light. Wearing blue light glasses can reduce the negative impact of blue light on your eyes and brain.