The dark side of blue light

Room lighting in the evening postpones the natural production of the ‘night hormone’ melatonin. A blue light filter on your screens often is not able to prevent this. Only since the industrial revolution have we started using artificial light inside of the house. Our biological clock is sensitive to the blue light that it contains. During daytime this isn’t a problem, but at night it keeps us active and alert.

 

 

 

Artificial light in the evening

Too much artificial light in the evening will shift our circadian rhythm (our 24-hours day-night rhythm) to a later time. Therefore, melatonin will be produced later and it will become harder to wake up in the morning. Moreover, it reduces the amount of deep sleep during the first sleeping cycle. It is scientifically proven that some people are genetically more sensitive to the exposure of blue light in the evening.

 

 

In the graph depicted above, the natural light intensity (measured in melanopic lux) is depicted in yellow. The gray lines are indications of the light intensity to which we are exposed indoors. The lack of a natural evening signal without blue light has a negative impact on our biological clock and sleep. Read the full article in Nature.

 

 

How the Somnoblue works. Five misconceptions about blue light blocking glasses 

 

 

 

 

Are standard blue-blocking computer glasses effective?

Many blue light computer glasses are offered nowadays. Many of these glasses only filter five to twenty percent of the blue light. As long as the glasses are yellow or translucent and if they don’t cover the eyes from above, they will allow most of the blue light to reach the eyes. Especially the light that reaches the eyes from above has major effects on our biological clock. Therefore, these products don’t meet the criteria for effective sleeping glasses.

 

 

 

 

The effect of Somnoblue

The blue light blocking sleeping glasses that we offer, filter the majority of light with a wave length smaller than 530 nanometer. By doing this, our brains receive a signal that night has come. This results in an optimized production of melatonin and may help you achieve a better quality of sleep. Here you can find scientific findings concerning blue light and sleep. 1, 2, 3

 

 

 

 

As the image below shows, blue light with a wave length of 420 to 530 nanometers has the largest effect on our biological clock. The sleep glasses filter the light with a wave length smaller than 530 nanometers. As a result, you see everything in an orange tint. The absence of blue light is a signal for the brain that night has come.

 

 

 

Intrinsic photosensitive retinal ganglion cells

Naturally, our body is programmed to ensure that energy, alertness, concentration, and other aspects relating to mental and physical performance peak during the day. This programming is done in our internal biological clock centered in our brain.

Special receptors in our eyes (so-called intrinsic photosensitive retinal ganglion cells)  send information to this internal clock about the color and intensity of light. It helps to the biological clock to keep it attuned to the natural alteration of light and darkness.

Blue morning light (wavelengths from 450 to 530 nanometre) is the natural sign for our body’s clock that the day has started. As a response, our brain signals our body to remain active. During night-time, the lack of 450 to 530 nm light normally promotes our brain to secrete melatonin.

Melatonin (the hormone of darkness) is a highly effective antioxidant and protects our cells and DNA from free radicals and oxidative stress. This hormone controls our circadian biology and affects mental and physical rest and recovery. Melatonin also helps to promote an optimal quality of sleep.

Although our body produces melatonin naturally, blue light during and prior to normal sleeping times hinders its natural production because it postpones the release of the night hormone melatonin. When worn prior to sleep, our blue light blocking Somnoblue glasses enables a more natural production of melatonin and promote a night of more natural sleep. Also, the orange glow of the glasses mimics an evening sunset. When used over a longer period of time, the glasses prime the brain (in the form of classical conditioning) for rest and sleep.  

 

Important advice: create a calm ritual in the evening

It is important to use electronical devices as little as possible before bedtime, even while using the glasses. It keeps the brains active. Try to relax in the evening, for instance by listening to music or by reading a book. Apart from the exposure to light, there are many other factors which influence your sleep pattern. Amongst others are stress, disturbed sleeping routines or depressions. If your complaints are so heavy that you have sleep deprivation frequently, please contact your general practitioner.

 

The importance of good sleep

In your life you will sleep between 25 and 30 years. Good sleep is essential for your health, mood, and performance. By using artificial light in the evening, people set back their biological clock, resulting in a delay of melatonin production. For these people, it is both harder to fall asleep and to wake up in the morning. Melatonin is a very powerful antioxidant, especially for the brain. It slows down damage to and aging of our brains. If the melatonin level is suppressed for a longer period of time, it may have a negative effect on your health and your sleep.

 

Sleep and health

Sleep is essential for our body and mind to function properly. While we sleep, the brain cleanses itself from toxins and waste. Moreover, it supplements itself with glucose – the fuel that allows the brain to work. Sleeping poorly one or two nights already has a disruptive effect on the functioning of our immune system and results in a craving for unhealthy food. Experiencing poor sleep for a prolonged time makes you susceptible to obesity, heart and vascular diseases and diabetes.

 

Sleep and Performance

While we sleep, our brain is provided with extra glucose. This is necessary for concentration, memory, and general performances. One bad night of sleep, for instance of four hours only, or multiple nights of five hours only, prevents the brains to fully recharge. According to Harvard Business Review, sleeping for four hours only for a longer period of time has the same effects on your performance as drinking six beers before going to work.

 

Sleep and Mood

A good night of sleep contributes to a good mood. As you might have experienced yourself, quality of sleep and mood are closely related. Bad or insufficient sleep may create tension, irritability, and stress. In the long-term, it even increases the risk of depressions or anxiety disorders.

 

 

Source: Phillips et al., 2019 

 

 

Somnoblue for shift work environments

In your life, you will sleep between 25 and 30 years. Good sleep is essential for your health, mood, and performance. By working night shifts you are exposed to artificial light at night and early morning, which affects your biological clock, resulting in a delay of melatonin production. For these people, it is not only harder to fall asleep, but if the melatonin level is suppressed for a longer period of time, it may have a negative effect on your health. The blue light blocking sleeping glasses that Somnoblue offers, filter the majority of light with a wavelength smaller than 530 nanometers. Also, these glasses filter all blue light from all directions. By doing this, our brains receive a signal that night has come. This results in an optimized production of melatonin and may help you achieve a better quality of sleep. Currently, our glasses are applied at 8 of the 10 largest hospitals in the Netherlands (e.g. Leiden University Medical Center, ACM and Radboud University Medical Center) 

 

 

Relevant scientific articles about sleep, fatigue and blue light 

 

Beccuti, & Pannain (2011). Sleep and obesity. Current opinion in clinical nutrition and metabolic care, 14(4) 

Cajochen (2007). "Alerting effects of light." Sleep medicine reviews 11.6 (2007): 453-464.

Chang, Anne-Marie, et al., (2015). "Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness." Proceedings of the National Academy of Sciences 112.4 (2015): 1232-1237.

Chellappa et al., (2012). "Human melatonin and alerting response to blue-enriched light depend on a polymorphism in the clock gene PER3." The Journal of Clinical Endocrinology & Metabolism 97.3 (2012): E433-E437.

Chellappa, et al., (2013). Acute exposure to evening blue‐enriched light impacts on human sleep. Journal of sleep research, 22(5), 573-580.

Gooley, Joshua J., et al., (2010). "Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans." The Journal of Clinical Endocrinology & Metabolism 96.3 (2010): E463-E472.

Golombek, D. A., & Rosenstein, R. E. (2010). Physiology of circadian entrainment. Physiological reviews, 90(3), 1063-110

Gezondheidsraad (2017). Gezondheidsrisico’s door nachtwerk Nr. 2017/17A, 2017 (PDF bron)

Kerkhof et al., (2018). Schermgebruik, blauw licht en slaap. RIVM Rapport 2018-0147. https://www.rivm.nl/bibliotheek/rapporten/2018-0147.pdf

Kayumov, Leonid, et al., (2005). "Blocking low-wavelength light prevents nocturnal melatonin suppression with no adverse effect on performance during simulated shift work." The Journal of Clinical Endocrinology & Metabolism90.5 (2005): 2755-2761.

Mortazavi., et al., (2018). "Blocking short-wavelength component of the visible light emitted by smartphones’ screens improves human sleep quality." Journal of biomedical physics & engineering 8.4 (2018): 375.

Phillips, A. J., Vidafar, P., Burns, A. C., McGlashan, E. M., Anderson, C., Rajaratnam, S. M., ... & Cain, S. W. (2019). High sensitivity and interindividual variability in the response of the human circadian system to evening light. Proceedings of the National Academy of Sciences, 116(24), 12019-12024

Shechter, Ari, et al., (2018). Blocking nocturnal blue light for insomnia: A randomized controlled trial. Journal of psychiatric research96 (2018): 196-202.

Rahman, Shadab A., et al., (2011). “Spectral modulation attenuates molecular, endocrine, and neurobehavioral disruption induced by nocturnal light exposure.” American Journal of Physiology 300.3 (2011): E518-E527.

Reiter, Russel J., et al., (2007). "Light at night, chronodisruption, melatonin suppression, and cancer risk: a review." Critical Reviews™ in Oncogenesis 13.4 (2007).

Reiter, Russel, et al., (2018). Mitochondria: Central organelles for melatonin′ s antioxidant and anti-aging actions. Molecules 23.2 (2018): 509.

Sasseville, Alexandre, et al., (2006). "Blue blocker glasses impede the capacity of bright light to suppress melatonin production." Journal of pineal research 41.1 (2006): 73-78.

Van der Lely et al., (2015). "Blue blocker glasses as a countermeasure for alerting effects of evening LED diode screen exposure in male teenagers." Journal of Adolescent Health 56.1 (2015): 113-119.