The Real Dangers of Artificial Light to Your Health
The Real Dangers of Artificial Light to Your Health
We are surrounded by artificial light sources in our daily life, whether it is the light in our office or from our phone screen. Artificial light can impact your health in a variety of ways, but why is this a problem? The problem lies in the color spectrum that artificial light uses. Nearly all types of light from the screens we use including our laptops, televisions, tablets and phones include a blue spectrum that is more intense than normal sunlight. Sunlight, by the way, incorporates all of the color spectrums.
The blue color spectrum can impact your health in several ways. First, blue light as part of normal sunlight is required by the body for just part of the day. Blue light is what triggers your body to get up and go. Take a plant, for example: The blue spectrum is the wake-up call for plants to open their blooms. The same is true for humans, it is the signal that tells the human body when it is time to get up and out of bed or to start the day. This is a unique spectrum with a unique function that wakes our body up. Blue light is also tied into our metabolism
Too Much Artificial Light Exposure Can Make You Sick
Maintaining natural 24-hour circadian rhythms is essential for your well-being.
Health experts are increasingly aware that limiting your exposure to artificial light—while making sure to get some exposure to natural light—within a given 24-hour cycle is key to staying healthy. New research shows that the last century of artificial light pollution is an environmental hazard that is causing our circadian rhythms—which have evolved since the beginning of time—to go haywire.
It's no wonder our chronobiological clocks are discombobulated. After relying on the sun, moon, and stars to guide our waking and sleeping hours for millennia, it's been less than 100 years since humans en masse have been exposed to artificial lighting—which has become omnipresent in the early 21st century.
From a historical perspective, it's hard to imagine that Thomas Edison didn't even invent the lightbulb until 1878. At the time, he declared, "We will make electricity so cheap that only the rich will burn candles." In 1882, Edison opened his Pearl Street Power Station which provided electricity to a handful of customer in lower Manhattan for the first time in history. Electricity and artificial lighting didn't became widely available in the United States until the 1930s.
The rising and setting of the sun influences every cell in our bodies and is literally hardwired into your neurobiology. Almost every organism on earth—from single-cell algae to humans—has an internal circadian clock that corresponds closely with the seasonal 24-hour cycles of darkness and light.
Human sleep patterns are largely governed by our internal circadian clock. In humans and animals, circadian patterns follow a 24-hour cycle which is directed by the circadian control center of the brain, called the suprachiasmatic nucleus (SCN), located in the hypothalamus.
In 2013, researchers at MIT reported that when circadian rhythm are thrown off, health problems including obesity and metabolic disorders such as diabetes can arise. People who work night shifts have an increased susceptibility to obesity and diabetes. The researchers at MIT also discovered a link between a disruption in circadian cycles and aging. In a statement,Leonard Guarente senior author of the paper said,
"Just about everything that takes place physiologically is really staged along the circadian cycle. What's now emerging is the idea that maintaining the circadian cycle is quite important in health maintenance, and if it gets broken, there's a penalty to be paid in health and perhaps in aging."
Today, a new animal study from the Netherlands reports that constant exposure to light triggered pro-inflammatory activation of the immune system, muscle loss, and early signs of osteoporosis.
The July 2016 study, "Environmental 24-Hour Cycles Are Essential for Health," was published in the journal Current Biology. In a statement, lead author, Johanna Meijer, said,
"Our study shows that the environmental light-dark cycle is important for health. We showed that the absence of environmental rhythms leads to severe disruption of a wide variety of health parameters The good news is that we subsequently showed that these negative effects on health are reversible when the environmental light-dark cycle is restored."
The latest research also observed physiological changes due to artificial light exposure that were all indicative of "frailty" as is typically seen in people or animals as they age.
In June 2016, the latest New World Atlas of Artificial Night Sky Brightness report was published stating that one-third of the Earth’s population cannot see the Milky Way. For those of us living in North America, a staggering 80% of the U.S. population cannot clearly see the nighttime constellations. The excessive amount of light pollution in our homes, towns, and cities is affecting our health on a global scale.
To investigate the relationship between a loss of the light-dark cycle and disease, Meijer and colleagues, including Eliane Lucassen, exposed lab mice to constant ambient light while measuring several major health parameters. Analysis of the animals' brain activity showed that constant light exposure reduced the normal rhythmic patterns in the brain's central circadian pacemaker—the suprachiasmatic nuclei (SCN)—by 70 percent.
Interestingly, the disruption of organic daily light-dark patterns also triggered a reduction in the animals' skeletal muscle function making the mice physically weaker, as measured in standard tests of strength. Their bones also showed signs of deterioration. After constant artificial light exposure, the animals also entered a pro-inflammatory state normally observed only in the presence of pathogens or other harmful stimuli
The good news is that within two weeks of being returned to a standard light-dark cycle, the SCN neurons rapidly recovered their normal rhythm, and the animals' health problems were reversed.
"We used to think of light and darkness as harmless or neutral stimuli with respect to health," Meijer concluded. "We now realize this is not the case based on accumulating studies from laboratories all over the world, all pointing in the same direction. Possibly this is not surprising as life evolved under the constant pressure of the light-dark cycle. We seem to be optimized to live under these cycles, and the other side of the coin is that we are now affected by a lack of such cycles."
The Conclusion: Types of Daily Light Exposure Matter . . . "Dim All the Lights!"
For optimal health, the latest research suggests that taking a two-pronged approach to keeping our circadian rhythms in sync should be a top priority. First, you should make an effort to be expose yourself to some type of ambient, natural sunlight every day. Second, you should try to avoid excessive artificial light throughout the day by avoiding windowless spaces (whenever possible), keeping house lights dim at night, and limiting electronic use at least an hour before bedtime.
Ideally
your daily waking and sleeping schedule should flow with seasonal fluctuations based on when the sun rises and sets in your region of the world or zip code. Of course, scheduling your life based on rising and setting of the sun is basically impossible for most of us living in a modern society, which doesn't make circadian rhythms a top priority. Maybe someday, increased awareness about the detriments of too much artificial light exposure will lead to policy changes that allow work schedules to ebb and flow with the seasons?
Luckily
there are a variety of easy things within the locus of your control that you can do here and now to limit light pollution in and around your home after dark. Creating simple habits such as turning off or dimming any lights in rooms that aren’t inhabited is a good place to start. Also, if you like bright light, laser-focusing or shielding high wattage light bulbs with ‘barn doors’ creates a spotlight effect that doesn’t illuminate or 'pollute' a broader area than necessary. All of these things can reduce light pollution and your exposure to unnecessary artificial light, especially after sundown.
Lastly
a May 2016 study found that smartphone use combined with social networking late at night is disrupting the natural circadian rhythms and sleep patterns for people of all ages and nationalities around the globe. Smartphone use during the day obviously leads to excessive screen time, but bedtime use of any digital technology exposes you to more artificial light, throws off your SCN, and exacerbates sleep disturbances. In a statement, lead author of the study Daniel Forger said,
"Across the board, it appears that society governs bedtime and one's internal clock governs wake time, and a later bedtime is linked to a loss of sleep. At the same time, we found a strong wake-time effect from users' biological clocks—not just their alarm clocks. These findings help to quantify the tug-of-war between solar and social timekeeping."
Among other side effects, poor sleep hygiene reduces cognitive function and increases depression risks. Sleep hygiene is defined as, 'habits and practices that are conducive to sleeping well on a regular basis and having full daytime alertness.'
Why are LED Lights Bad for Your Eyes?
Light emitting diodes (LED) are made from crystals that may contain materials such as phosphorous in order to produce a distinct color. Overlapping colors, particularly the primary colors of red, blue and green, produce "white" light. No industry standard exists for brightness levels, but many manufacturers use the terms "super-bright" and "ultra-bright" to describe LED bulb intensity.
The warning
All LEDs do not require government-regulated eye safety labeling, but is is best not to stare into the beams at close range. TheLEDlight.com states that LED lights, whether white, blue, infrared or ultraviolet, are very bright and can be intense enough to injure human eyes.
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Photochemical Action
LED Lamps for Reading
Permanent eye damage can be caused when staring into high bright LEDs. Staring into an intense light, such as an LED, can have the same effect on the retina as using the sun's rays to make paper smoke or to start a fire using a magnifying glass. This is called photochemical reaction and the potential damage depends on the light intensity as well as the length of exposure.
To date, there are no scientific studies showing that reading by LED light causes damage to the eyes.
The Effects of Black Lights on Vision
The eyes have a number of built-in defenses to protect vision
Black lights emit UV radiation that can be harmful to the eyes and can affect vision over time. Although the eyes do have some built-in defenses, these weaken over time and some of the defenses themselves can affect vision.
Black lights emit UV-A radiation
and what is known as blue light. Elaine Kitchel, a Low Vision Research Associate, says that these light rays have been found to prevent the retinal cells from forming cytochrome oxidase. This chemical transports oxygen to the cells involved in vision. Without cytochrome oxidase and without oxygen, the cells of the eye begin to die. The lesions that occur may be scattered so it isn’t until many have formed that vision loss is noticed.
Limiting exposure to black lights and UV radiation is thought to limit possible harmful effects, but Kitchel explains that time has nothing to do with it. It’s not how long or how frequently your eyes are exposed to such light that matters. Researchers have found that retinal damage is a feature of exposure to these wavelengths, regardless of duration or frequency.
The Temporary Effects
The Canadian Centre for Occupational Health and Safety says
that UV radiation can result in conjunctivitis and photokeratitis. Conjunctivitis is inflammation of the membrane covering the whites of the eyes and the inside of the eyelids. Photokeratitis is inflammation of the cornea. The watering of the eyes that occurs because of these conditions can blur vision. Both of these are temporary conditions
The Long-Term Effects
Dan Roberts, Director of Macular Degeneration Support, says
that over the years, cellular debris buildup in the retina can make the eyes even more sensitive to damage from light exposure. Cataracts, the protein clumps in the lens of the eye, are actually the eyes' defense mechanism. This cloudy, pearl-like effect limits UV radiation damage to the retina but also increasingly limits vision.
The Defenses
The eyes use a number of chemical defenses against UV radiation, says Dan Roberts. There are multiple built-in chemical defenses, and antioxidants in the diet such as vitamin C and E can also help to protect the eyes from black light. These defenses weaken with age, disease, neglect and poor nutrition.
As we age, the lens of the eye begins to yellow. This darkening of the lens helps filter black light and other UV radiation. Children, however, haven’t developed this protective yellowing and are more at risk for retinal damage from black light and UV radiation. Surgery to remove cataracts also removes the protective yellowing.
The Health Effects of Artificial Light
Why is artificial light a concern?
Artificial light is composed of visible light as well as some ultraviolet (UV) and infrared (IR) radiations, and there is a concern that the emission levels of some lamps could be harmful for the skin and the eyes. Both natural and artificial light can also disrupt the human body clock and the hormonal system, and this can cause health problems. The ultraviolet and the blue components of light have the greatest potential to cause harm.
Some people with diseases that make them sensitive to light claim that the energy-saving lamps (mainly compact fluorescent lamps (CFLs) and light emitting diodes (LEDs)) that have been brought to replace incandescent lamps, make their symptoms worse and play a role in a wide range of diseases. They also argue that protective measures such as covering the lamps with a second glass envelope (which decreases the UV-emissions), are ineffective.
Overexposure to UV causes burns in the short term and, over long periods of time, contributes to the risk of developing skin cancer (melanoma) as well as squamous cell carcinoma (SCC) and basal cell carcinoma, (BCC). According to a worst case scenario the highest measured UV emissions from lamps used in offices and schools, but not the very low emissions lamps used for household lighting, could add to the number of SCCs in the EU population.
Using some types of CFLs for long periods of time at close distances may expose users to levels of UV nearing the limits set to protect workers from skin and eye damage.
What effects on health have been observed?
Exposure to light at night while awake, such as in shift work, may be associated with an increased risk of breast cancer and also cause sleep, gastrointestinal, mood and cardiovascular disorders. However, these effects are due disruption of the natural circadian rhythm, regardless of the type of illumination
Visible and IR radiations from artificial lights are unlikely to have any effects on health, unless they are extremely intense and used at close range.
There is no evidence that short-term exposure to lamps used normally in offices or at home would cause any damage to the eye. The blue component of visible light can harm the retina but this is only caused by accidental exposure to sunlight or to very high intensity artificial lights so is rare.
There is no consistent evidence that long-term exposure to blue light at lower intensity causes any damage to the retina.
Long-term exposure to UV from sunlight may damage the cornea and cause cataracts but using artificial light normally is very unlikely to have any similar effects.
Most people with skin conditions that make them sensitive to light find that sunlight brings on symptoms but some of the most sensitive patients also react to artificial light. The blue or UV component of light are particularly effective at aggravating the skin lesions of chronic actinic dermatitis and solar urticaria, and in the case of lupus erythematosus they make worse both the skin reactions and the disease itself. It is estimated that 1 in 3000 people in Europe is affected by such conditions. These patients should avoid light sources with UV emissions. For instance, if they use CFLs it would be better if they used those with a double envelope. An even better option for some people might be LEDs, because they do not emit UV.
What are the effects on people who have conditions that make them sensitive to light?
The effect of light on patients with eye conditions that are sensitive to light, varies widely from one person to another, depending on their genetic makeup. All patients with retinal dystrophy should wear special protective glasses that filter harmful wavelengths.
Short-term UV effects from artificial lighting on healthy people are thought to be negligible. It is not possible to assess long-term risks because there are no exposure data but one can make estimates considering a worst-case scenario. This assumes typical exposures at work and in school to CFLs with the highest level of UV radiation, although in practice, exposure to fluorescent lamps will be lower than this.
Modern CFLs are essentially flicker-free but there could be some residual flicker and, even if the flicker is not noticeable, it may still be perceived by the brain. There is no scientific evidence to evaluate whether the lights considered here have any effect on conditions such as Irlen-Meares syndrome, myalgic encephalomyelitis, fibromyalgia, dyspraxia, autism and HIV.
How and where are people exposed to artificial light?
Exposure to UV from artificial light is equivalent to one week vacation in a sunny destination
The annual dose of UV on the skin from the worst case scenario is equivalent to that from a one-week holiday in a sunny destination.
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