But, with the introduction of artificial light in our homes, workplaces, cars, technology, etc., our environment changed significantly. Instead of exposure to the sun’s nourishing spectrum, we are bombarded with unnatural blue light from day-to-night and our health has suffered as a result.
What is Blue Light?
Light exists along a spectrum (the electromagnetic spectrum) from high energy to low energy and is most commonly measured in nanometers (nm). Only a very limited amount of the entire electromagnetic spectrum is visible light (380-740nm), with the remainder being invisible (2).
Blue light is found in the visible portion of the spectrum and is characterized by its high energy and short wavelength. We are exposed to natural blue light every day from the sun, with its presence being most dominant in the morning and gradually subsiding into the afternoon/evening3.
Not All Blue Light Is Created Equally
Humans operate on a circadian clock, which uses the light environment to tell time and stimulate biologic functions. This process is carefully coordinated by the Suprachiasmastic Nucleus (SCN), which is located in the hypothalamus. Proper circadian alignment is a critical component of optimal health, energy production and longevity (3).
Natural blue light is a powerful agent for circadian entrainment and interacts directly with a photoreceptor located in the eye and skin called melanopsin. The presence of blue from the sun’s morning spectrum stimulates the release of hormones like cortisol and serotonin that contribute to feelings of wakefulness. The absence of blue in the later part of the day stimulates the secretion of melatonin, a powerful hormone responsible for regulating sleep and repair processes (3).
At a time when exposure to blue light came only from the sun, circadian alignment was a natural part of life. But today, another factor is at play - artificial light - and the consequences for our health are significant.
Artificial light sources do not resemble the sun’s frequency at all, containing higher levels of blue and green without the natural balance of red. The presence of blue and green stimulates wakefulness and most closely resembles late morning to noon (3).
Every time we look at a screen, turn on an LED, or even open our refrigerator, we are getting bathed in blue light. Unable to tell the difference between artificial and natural light, our body responds accordingly by initiating processes associated with daytime, including melatonin suppression and cortisol up-regulation (3). In a 24/7 world of constant work, entertainment, and technology, humans are no longer experiencing appropriate periods of light and darkness. The consequences of our modern state of chronic circadian disruption affect every cell in our body and manifest as metabolic disorders (4, 5, 6, 7), cancer (8), heart disease (9), poor sleep quality (10, 11), hormonal imbalance (11), lack of energy (12), cognitive dysfunction (13, 14, 15, 16, 17, 18), obesity (19), mitochondrial dysfunction (20) and much more.
In addition, blue light’s high energy wavelength has been shown to alter mitochondrial function, resulting in increased production of Reactive Oxygen Species (ROS), decreased production of energy, DNA damage, and apoptosis (cell death). This is particularly important as it relates to the retina, which contains the highest volume of mitochondria due to its substantial energetic demands. As a result, chronic exposure to artificial blue light can lead to myopia, macular degeneration, and glaucoma (21). The same effect has been observed in skin, resulting in DNA damage, pigmentation and accelerated aging (22, 23). While the sun contains blue light naturally, it is always balanced by low energy, longer wavelength red light, which has been demonstrated to increase cellular energy production and decrease the burden of ROS (24, 25, 26).
Although humans are just beginning to scratch the surface of blue light and the effect it has on our biology, we do have a viable, inexpensive solution for mitigating the harmful effect: blue light blocking glasses.
What Are Blue Light Blocking Glasses?
Blue light blocking glasses, or blue blockers, are glasses designed to filter down or completely eliminate the harmful blue light. These glasses can be recognized by their distinctive yellow or red tints. There are many different companies making these glasses, but not all are created equally - keep reading to learn about how to choose the perfect pair for you!
Learning From Our Mistakes:
We make mistakes too! Here are some quick tips we learned in the process of purchasing several pairs.
- Know your glasses size beforehand. If you happen to know the size glasses that fit your face best, then you are in luck! All I can say is we sure did not - in fact, it really wasn’t even a consideration at first.
- If you are unfamiliar with glasses measurements, here’s a quick run down: https://www.allaboutvision.com/eyeglasses/faq/eyeglass-frame-size.htm
- Your best bet is to go to a store that sells frames and get measured before you commit to any pairs or compare to a pair you may have already. Most sites selling blue light blocking glasses will have the measurement available so you will know they fit before you commit - if not, just ask!
- You can get blue blockers with prescription or have yours tinted! If you’re worried about your prescription, worry not! Many companies now offer prescription and magnified blue blockers. Just take a look around their website and make sure you know your prescription ahead of time.
- If you have a pair of glasses you really like and would like to turn into blue blockers, you can send them to a company to have them tinted. There are a number of services out there so do your research to make sure they are getting the job done!
- Ask for the specification sheet. Every company explains blue blocking with different terminology and to be honest, it can be quite confusing! The best option is to go right to the truth: the data. Most companies will be willing to share their spectral analysis so you can see for yourself - carefully analyze and compare brands so you make sure you’re getting a pair that fits your needs.
- Stray Away From Amazon. Unfortunately, glasses from Amazon simply do not block enough of the blue to make a difference. Although it may cost more to buy a quality pair, your health is an investment and it is certainly worth it. Not to mention, if you purchase a sturdy pair and take care of them, they will last a long time.
Get a day and nighttime pair
Many companies offer various pairs intended for daytime or night time use - some even offer a third option with very little tint intended for computer use. While it is certainly an added expense, these tints are designed to serve different purposes and be used during separate parts of the day. This makes it a necessity to purchase at least two pairs - one for day time use and one for night time use.
A day time pair of blue blockers will have a yellow tint and likely filter anywhere from 45-60% of the blue light spectrum or block 100% of a specific portion. Allowing some blue promotes wakefulness and more closely aligns with the sun’s spectral composition during the day. These should be worn until sunset (or a little before) and then exchanged for your nighttime pair of blue blockers.
A night time pair of blue blockers will be entirely red and should block 100% of the blue light spectrum. These mimic the complete absence of blue and presence of red, which is the natural spectral composition of sunset. Although using your night time blue blockers will promote the processes associated with sleep and repair, it is typically best to avoid technology/artificial light altogether at night as other considerations like flicker could still be detrimental to sleep quality.
Don’t Wear Them Outside!
There is no replacement for nature and you should never cover your eyes or skin when spending time outside. In fact, sunlight through the eye is critical to optimal health, which means wearing your blue blockers could quickly go from being a healthy practice into one that is actually detrimental. Take off your blue light glasses and take in all the sun you can get!
Our Favorite Blue Blockers
Lucia Eyes was created by a father/daughter team out of Texas after realizing the health hazards of blue light.
What They Offer:
They offer three blue blocking lenses that fit any frame they offer. These blue blocking options are: 45% blue blocking, 60% blue blocking and 100% blue blocking. These percentages stand for the amount of blue light the glasses block from entering your eyes. For example, a 45% lens means those glasses block 45% of the blue light spectrum, allowing 60% to pass through the glasses. We recommend 60% blue blocking for effective daytime blocking and 100% blue blocking for any time after 5pm.
In addition to offering three types of blue blocking options, Lucia Eyes provides several different frame style options for men, women, and kids. You are able to order prescription lenses and readers in their 45% blue blocking and 100% blue blocking glasses.
Once a style runs out, they often do not restock quickly or at all. We ran into this first hand after purchasing a few styles to try out. Also, if you wear prescription glasses, Lucia does not offer prescription in their 60% blue blockers.
Ra Optics is another American brand, founded by Matt Maruca, a young 20 year old who spent years as a kid constantly struggling with health issues. When Western medicine failed him, he began doing his own research which led him to uncovering the importance of mitochondrial health and the relationship between our light environment and chronic disease. Ra Optics was born out of this discovery with a mission to help mitigate the harmful effects of artificial blue light to prevent disease and improve quality of life.
What They Offer:
They offer two blue blocking lenses: Ultimate Day and Ultimate Night. The Ultimate Day blocks blue light from 400nm - 455nm. Ultimate Night block 100% of the blue spectrum from 400nm - 550nm.
Their frames are super sturdy and feel like they will hold up for a long time. The red tint of the night time glasses is very pleasing and offers the lease amount of distortion. They do offer prescription and reader options in all of their frames and tints as well.
Ra Optics has limited frame styles to choose from (at least for now).
BLUblox is an Australian company truly committed to helping customers understand blue light.
What They Offer:
They offer three different types of blue blocking lenses: BluLite (filters down blue light across spectrum), SummerGlo, (blocks 400nm - 450nm), and Sleep+ (blocks 400nm - 550nm). The BluLite option comes in a transparent, clear lens with minimal color distortion while the SummerGlo comes in a yellow tint to fully block blue light in the 400nm - 450nm. Their Sleep+ glasses are red tinted and 100% blue blocking just like Lucia and Ra Optics night-time options.
BLUblox makes their lenses in Australia and is able to add your desired prescription. You can order your prescription in any of their blue blocking lenses. We like that BLUblox thinks outside the box by offering customer the chance to send in their current/favorite frames to be fitted with whatever blue blocking tint and prescription. Additionally, their website is super helpful and full of resources.
Because they are an Australian brand, shipping to the USA can sometimes take longer and cost more because the glasses must pass through customs. Make sure you've researched the best fit for you because if you decide to return the glasses, you are responsible for the return shipping and customs costs.
Having trouble wrapping your head around what blue light is and what emits blue light? If your hand is raised, check out Understanding Blue Light for an in depth summary on what blue light is and the differences between natural and artificial blue light.
After gaining more insight on what blue light is from the Understanding Blue Light article, we can now dive deeper into how blue light disrupts circadian rhythm. In our opinion, not enough light is shed on the topic of blue light given it's impact on our biology. The more we can understand, the more we can optimize our health.