Age-related macular degeneration (AMD) is one of the most common causes of blindness in people over 55. AMD is caused by vascular pathology and ischemia (malnutrition) of the central retinal zone, which is responsible for central vision.
The best type of lamps for people with AMD are Halogen bulbs, as they are brighter than regular incandescent or LED light bulbs. This is why many people with macular degeneration (AMD) prefer these bulbs for their tasks. For example, doing things like reading bills, writing checks and performing hobbies.
Now even though LED bulbs are rapidly becoming people’s favourite light bulb for obvious reasons, such as low cost and efficiency. However, there are studies from U.S and Europe that have warned against some dangers of LED lights.
Main causes of loss of sight
The main causes of sight loss amongst the more than two million people living with sight loss are:
Research into lighting and AMD (macular degeneration )
Scientists from the U.S. and Europe warn that LED lights could be doing more harm than good.
There is a Spanish study published in the journal Photochemistry and Photobiology 2012 that found that LED radiation can cause irreversible damage to the retina, There also was an analysis of more than 4,000 people living in 11 separate regions of Spain and they established a link between heavy exposure to the LED street lighting and a doubling of the risk of prostate cancer, as well as a 1.5-times higher chance of breast cancer.
This is just from LED streetlighting, not LED in our homes.
Also, a report from the French Agency ANSES in 2019 warned of the “phototoxic effects” of blue light exposure, including an increased risk for age-related macular degeneration.
They also reported that exposure to the light of white LED bulbs, suppresses melatonin five times more than exposure to the light of high pressure sodium bulbs that give off an orange-yellow light.
Suppression of melatonin has been shown to increase relative risk for some types of cancer and also disrupts many of our body’s biological functions. It also appears that each LED street lamp has a wireless antenna on top for the control management system.
A lot right? But this isn’t the first time energy-saving lights have come under scrutiny for safety reasons. Compact fluorescent light bulbs, or CFLs, have been criticized for the mercury they contain and for the high levels of ultraviolet (UV) radiation they can emit.
It has been said that modern-day humans have their eyes open for roughly 6,000 hours a year, and are exposed to artificial light for the majority of that time.
Sánchez-Ramos, the Spanish scientist who conducted the Spanish study in 2012 suggests wearing good-quality sunglasses with UV filters, and eating a diet rich in vitamin A to protect the eyes from retinal damage.
The true effects of LED
It is suggested that the maximum limit for acute exposure should be revised, even if such levels are rarely met in home or work environments.
The French Agency for Food, Environmental and Occupational Health & Safety (ANSES) created a 400 page report distinguishing between acute exposure of high-intensity LED light, and “chronic exposure” to lower intensity sources.
You can find the French report here. (Bear in mind that it is in the French language).
The French agency also said that while less dangerous, even chronic exposure can “accelerate the ageing of retinal tissue, contributing to a decline in visual acuity and certain degenerative diseases such as age-related macular degeneration”.
Long-lasting, energy efficient and inexpensive, light-emitting diode (LED) technology has gobbled up half of the general lighting market in a decade and will top 60 percent by the end of next year, according to industry projections.
Long-lasting, energy efficient and inexpensive, light-emitting diode (LED) technology now accounts for almost 60% of the lighting market.
It uses only a fifth of the electricity needed for an incandescent bulb of comparable brightness.
But LEDs emit much higher quantities of blue light, which has one of the shortest wavelengths. The whiter or ‘colder’ the light, the greater the proportion of blue in the spectrum.
ANSES recommended people should buy ‘warm white’ LED lighting and limit exposure to LED sources with a high concentration of blue light.
They even said car manufacturers need to revisit how bright car headlights are.
The UK’s chief medical officer Dame Sally Davies has previously said blue light is an ‘important area of investigation’.
There is also a report from the European Commission from the Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) and their opinion on Potential risks to human health of Light Emitting Diodes (LEDs). You can read that report here.
What is the the typical course and symptoms of the age-related macular degeneration ?
Age-related macular degeneration occurs gradually, but then progresses very quickly. The typical symptoms of AMD is described by one of my patient: “If you see the horizon as a straight line, then I see it wavy. Silhouettes of people are blurry. Instead of a circle, I see an oval. I read, and the letters “dance”, and in the middle of each word is a a black hole that begins to grow“.
What is the primarily pathology signs of Age-related macular degeneration ?
As the macular degeneration progresses, small blood vessels that supply the central part of the eye “stick together”. As a result, retinal ischemia occurs. Our organism tries to compensate vessels insufficiency by creating other small vessels. However, these vessels are incomplete, their walls are so thin that the liquid part of the blood – plasma – flows through them and accumulates in the central parts of the retina that causes edema. And if this edema is not eliminated, a scar will form on the retina. This is the final stage that cannot be cured by anything.
What are the forms of AMD?
There are dry and wet form of AMD. Dry AMD is the most common form of AMD. It develops in 90% of patients with AMD. With dry AMD there is a slow destruction of the photosensitive cells of the macula with a gradual blurring of the central vision of the affected eye. Wet AMD affects 10% of all patients with AMD. This form is more severe than the early or intermediate stage of the dry form. With wet AMD, pathological vessels grow under the retina in the macula. The newly formed vessels are characterized by increased fragility and permeability, which causes fluid and blood to “leak” with the development of macular edema and damage to the retina.
Who is at risk for AMD?
The risks of AMD are:
- age more than 50 and older. The risk of developing AMD increases with age .
- According to research, smoking increases the risk of AMD by 2 times .
- Family history. People with family members with AMD are at higher risk of AMD .
- Overweight and obesity .
- Cardiovascular diseases .
- Working with an inappropriate light source .
Exposure to blue light has been linked to the development of age-related macular degeneration.
So should we be taking precautions to avoid developing the condition?
What is blue light?
Blue light! You may not fully be aware, but our eyes are regularly exposed to blue light more than you think. While this exposure comes primarily from the sun, LEDs (light-emitting diodes) which produce the light in screens for devices such as computers and phones, also produce a significant amount.
This is why most smart phones now have the blue light filter reduction option, when there is low level light, so that it does not damage our eyes as much in the long term.
Blue light is high-energy, short-wave light that is part of the visible spectrum. Whereas ultraviolet light (UV) is largely absorbed by the front of the eye, blue light passes through and reaches the retina.
These wavelengths can potentially damage the retina, due to their high energy, has been discussed for years. More recently however, several researchers have suggested that exposure to blue light might represent a risk for the development of age-related macular degeneration (AMD).
How does lighting affect the eyes?
Light is a type of electromagnetic radiation. All electromagnetic radiation is classified by wavelength into radio waves, microwaves, infrared light, the visible spectrum light, ultraviolet light, X-rays, and gamma rays.
The visible spectrum light has wavelengths from 380 to 740 nanometers. However, in addition to the visible spectrum light that is created by both natural and artificial source of light, they also create the ultraviolet light. The ultraviolet light may be classified into UVC (below 286nm), UVB (286-320nm) and UVA (320-400nm) types. UVC is created by the sun only and is blocked by the earth’s ozone layer, so it has zero impact on our health. UVB is solar energy that is absorbed by skin and cornea and causes sunburn and snow blindness. UVA is the most dangerous for human eye  by causing destruction of rods and cons.
Another feature of a light is color temperature. Color temperature is expressed in kelvins, a unit of measure for absolute temperature. Color temperatures over 5000 K are called “cool colors” (blue light), while lower color temperatures (2700–3000 K) are called “warm colors” (red light).
The source of warm colors are flame, low pressure sodium lamps (LPS/SOX), candle flame, sunset/sunrise, standard incandescent lamps, soft white incandescent lamps. The source of blue light are LCD or CRT screens, xenon short-arc lamp, tubular fluorescent lamps or cool white / daylight etc.
In the modern society eyes are exposed for a very long time to high levels of blue light (cell phone screens, artificial light LED, neons etc . In the study was determined that retinal cells are more sensitive to light-induced damage when exposed to light emitted by blue (464 nm) LEDs than when exposed to green (522 nm) or white LEDs (wavelength peak at 456 and 553 nm) of the same intensity (0.38 mW/cm2) . Compared with age-matched controls, patients with advanced age-related macular degeneration (geographic atrophy or disciform scarring) had significantly higher exposure to blue or visible light over the preceding 20 years (odds ratio, 1.36 [1.00 to 1.85]) . T
In addition, the type of illumination influenced the extent of the retinal damage following light exposure. For example, rats raised in complete darkness showed greater susceptibility to light-induced retinal damage, than rats in a 5 lux light-dark cycle .
Finally, the severity of light-induced retinal damage changes with the time of the day. For example, rats are three to four times more susceptible to light damage at night (01:00) than during the day (09:00 and 17:00) .
A recent study conducted with an animal model reported that blocking UV light and blue light with yellow-tinted intraocular lenses materials (400–450 nm) could protect the retina .
Although LED and blue light has been proven to not be beneficial for people with AMD, in fact it is not beneficial for anyone ultimately. We must take appropriate precaution to reduce the risk of a damaged eye retina in the long term.
Thus, reducing the amount of blue light, UVA and UVB ultraviolet light may help to reduce the risk of development macular degeneration. To reduce the likelihood of developing macular degeneration, use warm light at home. Try to minimize spending time in front of cold light sources (telephones, TV displays, neon lamps), or at least to have warm light sources around, which eliminate the harmful effects of cold light on your retina. Try to minimize the time spent on the screen at night time, better to work during the day.
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