Although our ancestors moved out of caves hundreds of years ago, it seems like many…
We’re constantly under the glare of artificial lighting, with modern lighting systems brightening our homes and offices and with our eyes constantly on one screen or another. Artificial light is almost impossible to avoid, but unfortunately it does have its risks. The components of artificial lighting have an adverse affect on your physical and mental health, but how bad is the issue really?
It’s predicted that by 2020, 90% of our light sources will use LED lighting meaning that almost everywhere we turn we’ll be exposed to artificial light sources that are potentially harmful to us. By being aware of the possible dangers of artificial lighting, we can better protect ourselves from harmful light exposure and continue to enjoy all the benefits of modern lighting solutions.
How does light work?
Light is made of electromagnetic radiation that moves in wavelengths. These wavelengths vary in size and the size of the wave affects the strength of its energy; the shorter the wavelength, the stronger it’s energy.
Visible light is the one part of the electromagnetic spectrum that we can see. The eye’s retina is exposed to visible light wavelengths between 400 and 700 nm (nanometres), as well as some short infrared wavelengths. Out of all the wavelengths that make up visible light, it is blue light that is a cause for concern because blue light has a very short wavelength. This means it has a high energy level and in high doses blue light can be hazardous to our health.
There is no way to avoid blue light; it is present in both artificial lighting and the natural sunlight we encounter outdoors. In certain doses blue light is beneficial to us, but it becomes harmful when we are exposed to it too often. Because of how commonplace artificial lighting is in today’s society, there is a greater risk of over-exposure to blue light.
The main issue with artificial lighting is the colour spectrum it uses because artificial light includes a blue spectrum that is more intense than it is in natural sunlight. Research suggests that the LEDs in the artificial lighting of smartphones, tablets and computers do not emit white light, but actually blue light at peak emission (ranging from 400-490nm). This means that when we’re looking at the digital screens on our mobile phones and computers our natural sleeping and waking patterns (the circadian rhythm) can become disrupted.
With 43% of adults working in a job that requires the prolonged use of a computer or digital screen, it’s important to be aware of the potential dangers of blue LED light sources to avoid over exposure to dangerous types of light.
Luckily, exposure to blue light is not all bad. Natural sources of blue light increase our wakefulness and regulate our circadian rhythm so we rely on blue light to regulate our bodies. It is tied to our metabolism and gives us energy; it’s blue light for example that encourages plants to bloom.
The dangers of artificial light
- Artificial light and our circadian rhythm
- Artificial light and cancer risk
- Artificial light and macular degeneration
- Avoiding damage from artificial light
Artificial lighting and our circadian rhythm
Your circadian rhythm is your body’s internal clock that regulates feelings of tiredness and wakefulness. Outside factors such as light effects the functioning of your circadian rhythm because your body relies on light to regulate your body’s metabolism.
Your circadian rhythm is controlled by a part of your brain called the hypothalamus. When it is dark your eyes send signals to the hypothalamus, triggering it to release melatonin (a hormone key to your circadian rhythm), which makes your body tired. When you are exposed to too much light, the hypothalamus does not receive these signals and your melatonin levels remain low which can cause serious medical issues.
This is why being exposed to artificial light and digital devices that use blue LED light can ruin your sleeping pattern. Sleep deficiency caused by artificial lighting can lead to further problems with your mental and physical health and cause issues such as:
- Negative effects to your memory, making it harder for your brain to retain information.
- A neurotoxin build up that causes further sleep problems.
- Disruption to your melatonin cycle that can interfere with the hormones that control hunger, potentially increasing your risk of obesity.
- Increased risk of breast cancer and prostate cancer.
Artificial lighting and cancer risk
Studies have connected the diagnosis of breast cancer and prostate cancer to over-exposure to artificial light. This is because of how light interferes with the production of melatonin, which should peak at night (when it is naturally dark) and then reduce during the day (when it is naturally light).
The Barcelona Institute for Global Health performed a study that analysed how residents in large cities might be affected by the heavy exposure to artificial blue lighting at night (because of street lighting). The results found that residents of these cities had double the risk of developing prostate cancer and 1.5 times higher risk of developing breast cancer.
Similarly, studies have found that people who perform regular night shift work are more susceptible to developing breast cancer and prostate cancer because their bodies are exposed to both natural and artificial light 24 hours a day and are therefore unable to develop a regular circadian rhythm.
The results of these studies show that it is imperative for our physical health that our bodies get a break from lighting solutions that use LED blue light, especially when it is dark.
Artificial lighting and macular degeneration
Blue light has the potential to cause damage to our eye’s retina. This happens when blue light penetrates the macular pigment of the eye which causes the retina to breakdown. This makes the eye more vulnerable to cell degeneration which can lead to problems such as age-related macular degeneration (AMD), glaucoma and cataracts.
Age-related macular degeneration is a disease where the central vision is lost. It is the most common cause of blindness in the elderly population and accounts for 8.7% of blindness worldwide. There are several ways that blue light can cause AMD to develop, however the most common reason is retinal damage by photochemical mechanism. Photochemical reactions happen in normal, ambient conditions and involve a reaction between energetic photons and an absorbing molecule in the presence of oxygen, which leads to the generation of reactive oxygen species (ROS) that are highly toxic to the retina.
Our Ocular Lens Pigment (OLP) is what protects our eyes from light exposure and the development of macular degeneration. Our eye’s natural defence system works by using both melanin and our OLP to selectively limit the amount of blue light that reaches the retina of our eye.
Children and older people are most vulnerable to developing AMD. The Ocular Lens Pigment that protects our eyes from damage only forms in the lens of the eye during the late teenage years and whilst the OLP is forming, the amount of melanin in the eye gradually decreases. Melanin is a substance in our hair, skin and eyes that absorbs harmful UV and blue light, keeping us protected from over exposure to light. Having lower melanin levels makes children and teenagers more vulnerable to blue light exposure and susceptible to developing AMD.
Our melanin levels decrease naturally as we age, which means that older people become exposed to higher levels of blue light, with a greater risk of developing AMD. In fact, by the age of 65 around half of our protection on our eyes is gone, which significantly increases our susceptibility to developing eye diseases such as macular degeneration.
Early stages of AMD are yellowish deposits (drusen) and pigmentary changes of retinal pigment epithelium (RPE) alongside significant loss of vision. The advanced stages of AMD are dysfunction and death of photoreceptors and ultimately the irreversible loss of the central vision.
There have been significant advances in the management and prevention of AMD, and with the introduction of anti-angiogenesis therapy which can prevent blindness and in some cases, restore vision. However, because treatment is expensive and not available to everyone, it is important that awareness of AMD is spread so that symptoms of early stages are caught before they develop into anything more severe.
Avoiding damage from artificial light
You can take action to counteract the hazards of visible light and avoid damage to your physical and mental health. The easiest way to do this is to regulate your exposure to artificial lighting. By developing a routine that gives your body a significant break from artificial lighting especially during the evenings before sleeping, you can ensure that your body gets the opportunity to produce a healthy level of melatonin which will help you to develop a regular sleeping pattern that will keep your mind and body healthy.
Because blue light affects melatonin production, you should try not to use your smartphone or computer before sleeping. Most smartphones now have a “night time” mode, which is a blue light filter that will help to prevent artificial light disrupting your sleep pattern.
The Schepens Eye Institute recommends the use of sunglasses to protect against harmful blue and UV light outdoors. Many opticians sell prescription eyewear with melanin lenses to help prevent the development of macular degeneration especially during the years where people are more vulnerable to developing the disease.
You could also consider changing the types of lights you use in your home and office every day. Installing natural light sources and lighting solutions into your home or workplace that do not require the use of LED blue lights such as a natural light lamp or the Solarspot, could have a positive overall effect on your physical and mental health. The Solarspot is a lighting system that uses natural lighting from outside to brighten your home. By lighting your house with natural instead of artificial lighting, your body will be less exposed to a harmful amount of blue light that will keep your body awake and alert longer than it needs to be.