Blue light—a potential issue to sleep problems & more

Do you experience light sensitivity, headaches, migraines, sleep problems, fatigue, decreased eyesight, muscle/joint pain, or other issues? As strange as it may sound, all these issues could be related to light.

In this article, I explain the potential harms of blue light, and I go into a possible solution: blue light-absorbing glasses.

Blue light

First, let’s talk about blue light—the potential culprit of your issues.

Blue wavelengths are of the highest energy in the visible light spectrum. A component of natural sunlight, they are beneficial during daylight hours because they boost attention, reaction times, and mood.^[1]Blue light has a dark side (2020) | Harvard Health Publishing But blue light can cause some issues during the day; and at night, blue light can disrupt your sleep and your body’s inner clock, called the circadian rhythm. And with the proliferation of electronics with screens and energy-efficient lighting such as LED, we are getting increasingly exposed to blue wavelengths.

The harmful effects of blue light

Not only can blue light affect your sleep/wake cycle, but it also has an effect on the production of key hormones and neurotransmitters and metabolic activity. Consequently, it affects virtually every process in the body, and blue light emissions can be detrimental to the health of your eyes, cells, brain, and body as whole. Here are various ways in which blue light can cause problems:

Eyestrain & reduced eyesight

Blue light increases reactive oxygen species (ROS), which causes oxidative stress. This can cause eyestrain, headaches, and cell death (apoptosis) in the eyes. In other words, too much blue light can be very bad for eye health,^[2]Mitochondria as Potential Targets and Initiators of the Blue Light Hazard to the Retina (Tao, Zhou, & Zhu, 2019)^[3]Why our mitochondria need sunlight (2023) | Allison Clark Intuitive and may even cause retinal damage and a loss in eyesight.^[4]Role of Oxidative Stress in Ocular Diseases: A Balancing Act (Shu et al., 2023)

Brain functions

Melanopsin is a type of photopigment and one of a myriad of light-sensitive retinal proteins. It plays an important role in non-image-forming visual functions, and cognitive and affective processes.^[5]Melanopsin: From a small molecule to brain functions (Duda et al., 2020) As exposure to blue light reduces melanopsin,^[6]Exposure to Blue Light Reduces Melanopsin Expression in Intrinsically Photoreceptive Retinal Ganglion Cells and Damages the Inner Retina in Rats (Ziółkowska et al., 2022) it can undermine sleep, your circadian rhythm,^[7]Melanopsin: From a small molecule to brain functions (Duda et al., 2020) and various brain functions and mood-related behaviors. For instance, it can cause depression known as seasonal affective disorder (SAD).^[8]Melanopsin-expressing Retinal Ganglion Cells Mediate Light Modulation Of Cognitive Functions And Mood Related Behaviors (LeGates et al., 2011)

Fatigue

Mitochondria are membrane-bound cell organelles that produce chemical energy used to power cells. This energy is stored in a small molecule called adenosine triphosphate (ATP),^[9]Mitochondria (2023) | National Human Genome Research Institute thus allowing cells to store and use energy. ATP also allows muscles to contract, and it plays an important role in protein synthesis, among other things.^[10]Adenosine triphosphate (ATP) | Physiopedia And since blue light causes reduced ATP,^[11]Mitochondria as Potential Targets and Initiators of the Blue Light Hazard to the Retina (Tao, Zhou, & Zhu, 2019)^[12]Why our mitochondria need sunlight (2023) | Allison Clark Intuitive it could contribute to feeling depleted and fatigued.^[13]Muscle fatigue: general understanding and treatment (Wan et al., 2017)

Sleep problems

Blue light—and in particular the use of electronic devices such as E-readers before bedtime—suppresses levels of the sleep-promoting hormone melatonin,^[14]Mitochondria as Potential Targets and Initiators of the Blue Light Hazard to the Retina (Tao, Zhou, & Zhu, 2019)^[15]Why our mitochondria need sunlight (2023) | Allison Clark Intuitive which prolongs the time it takes to fall asleep (called sleep onset latency), delays the circadian clock, delays and reduces the amount of REM sleep (restorative sleep implicated in bodily repair and emotional processing),^[16]Physiology of sleep (Brinkman, Reddy, & Sharma, 2022)^[17]Overnight Therapy? The Role of Sleep in Emotional Brain Processing (van der Helm & Walker, 2010) and reduces alertness the following morning. As such, blue light can cause sleep deficiency and disrupt circadian rhythms, both of which can have adverse impacts on performance, health, and safety.^[18]Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness (Chang et al., 2014)^[19]E-Readers Foil Good Night’s Sleep (Peter, 2015) | Harvard Medical School

Bodily repair

Chronic exposure to blue light, especially after sunset, has been proven to disrupt our body’s circadian rhythm.^[20]Blue light has a dark side (2020) | Harvard Health Publishing Since the circadian rhythm is a timing system that controls a variety of functions, the main effect of this phase delay can be seen in the suppression of natural melatonin production.^[21]Blue light from light-emitting diodes elicits a dose-dependent suppression of melatonin in humans (West et al., 2011) Melatonin is the hormone responsible for decreasing metabolic activity, slowing down our brain waves, and putting us to sleep. It is also responsible for cellular repair; it is the body’s most important antioxidant, anti-aging, anti-cancer molecule.^[22]Melatonin in Cancer Treatment: Current Knowledge and Future Opportunities (Talib et al., 2021)

Chronic disruption of the circadian rhythm and melatonin production by exposure to blue light at night can lead to long-term health consequences as the result of lack of cellular repair, in particular, increased degeneration of mitochondrial function.^[23]Circadian Regulation of Mitochondrial Dynamics in Retinal Photoreceptors (Chang et al., 2018) The majority of modern chronic illnesses are mitochondrial in origin,^[24]The Key Role of Mitochondrial Function in Health and Disease (San-Millán, 2023) meaning they are due to a failure of natural energy production. Hence, it is critically important to protect our natural melatonin production by blocking blue light at night.

Solutions

So, one solution is to cut out blue light-emitting sources. So no screens or LED lights; use candles, red or orange light bulbs, or a fireplace. But cutting out screens from your life is obviously a very drastic measure, and is probably not going to be feasible in our modern life. And even still, the Sun emits blue light as well.

So a better solution to deal with blue light is to wear blue light-absorbing glasses. Different brands may have a broader range of different tinted glasses, but you will generally find they are divided into two categories:

Daylight lenses

• Use: Used to protect against exposure from man-made light sources during the day—whether on the computer, at the office, or at school.
• Function: Eliminate eyestrain, headaches, and afternoon fatigue. Used to relax your mind, lift your mood, and increase your productivity.

Sunset lenses

• Use: Used between sunset and bedtime, whenever you are exposed to common light sources such as LEDs or screens. Note that Sunset Lenses are not necessary when there is no blue light (as with candles, fire light, and red or orange light bulbs).
• Function: Relax naturally, fall asleep more easily, sleep more deeply, and wake up with more energy.

In the diagram below, you can see the parts of the wavelengths of LED light that get filtered by blue light-absorbing lenses.

I’ve seen blue light-absorbing glasses at various price points, although I can’t say how effective the cheaper ones are. On the higher end, Ra Optics and TrueDark glasses offer a range of glasses that absorb varying degrees of blue light, with their dark red-tinted glasses blocking 98% of blue light.

In a review comparing both glasses, Ra Optics marginally outperformed TrueDark glasses,^[25]Ra Optics vs TrueDark – Which Blue Blockers Are Best? (2023) | The Sport Review so I expect TrueDark will be a great choice as well. We only have experience with Ra Optics ourselves, and haven’t tested other ones, so I would do your own research to find glasses with the best performance within your budget. If you do end up trying Ra Optics or TrueDark, or if you have experience with other brands, we would love to hear whether they worked for you!

If you want to go for Ra Optics, they kindly offered our readers a discount of 15%. Use the code embraceautism on checkout to get 15% off your purchase!

Dr. Natalie Engelbrecht ND RP has been using both the daylight and sunset glasses from Ra Optics, which have reduced her headaches and improved her sleep hygiene, allowing her to fall asleep sooner and improving her quality of sleep. So if you’re looking for a solution to one or multiple problems outlined in this article—do give blue light-absorbing glasses a try!