author={Burkhart Kimberly and Phelps James R.},
  journal={Chronobiology International},
  pages={1602 - 1612}
All light is not equal: blue wavelengths are the most potent portion of the visible electromagnetic spectrum for circadian regulation. Therefore, blocking blue light could create a form of physiologic darkness. Because the timing and quantity of light and darkness both affect sleep, evening use of amber lenses to block blue light might affect sleep quality. Mood is also affected by light and sleep; therefore, mood might be affected by blue light blockade. In this study, 20 adult volunteers were… 
A Randomized Trial of the Impact of Amber Versus Blue Glasses on Sleep Quality, Energy and Mood
Evidence supports the claim that circadian rhythms, the approximately 24 hour cycle of activity in the body that controls energy level and mood, might have an effect on far more than just the sleep-wake cycle.
Interventions to reduce short-wavelength (“blue”) light exposure at night and their effects on sleep: A systematic review and meta-analysis
There is some, albeit mixed, evidence that wearing color-tinted lenses in frames to filter short-wavelength light exposure to the eye before nocturnal sleep can improve sleep, particularly in individuals with insomnia, bipolar disorder, delayed sleep phase syndrome, or attention-deficit hyperactive disorder.
Dim light, sleep tight, and wake up bright – Sleep optimization in athletes by means of light regulation
Light regulation may be considered a potentially effective strategy to improve subjective sleep, but less obtrusive methods should be explored to increase protocol compliance.
Restricting short-wavelength light in the evening to improve sleep in recreational athletes – A pilot study
Blocking short-wavelength light in the evening by means of amber-lens glasses is a cost-efficient and promising means to improve subjective sleep estimates among recreational athletes in their habitual home environment.
A randomized controlled trial on the effects of blue-blocking glasses compared to partial blue-blockers on sleep outcomes in the third trimester of pregnancy
The use of blue-blocking glasses compared to partially blue- blocking glasses in a group of healthy pregnant participants did not show statistically significant effects on sleep outcomes, and research on the effects of blue light blocking for pregnant women with sleep-problems or circadian disturbances is warranted.
Treatment of attention deficit hyperactivity disorder insomnia with blue wavelength light-blocking glasses
Despite only partial compliance with intervention instructions, subjects completing the study showed subjectively reduced anxiety and improved sleep quality on multiple measures, suggesting blue-blocking glasses are a potential insomnia treatment for more compliant subjects with ADHD insomnia, especially those with prominent sleep delay.
Do green-blocking glasses enhance the nonvisual effects of white polychromatic light?
The effects of polychromatic white light containing blue and green components on ipRGCs are apparently increased by removing the green component.
Sustained effects of prior red light on pupil diameter and vigilance during subsequent darkness
The suggestion that exposure to intense red light affects vigilance during subsequent darkness, was confirmed in a controlled polysomnographic study that indeed showed a post-red facilitation of sleep onset and the possibility of using red light as a nightcap is suggested.


Blue blocker glasses impede the capacity of bright light to suppress melatonin production
This hypothesis that cutting the blue portion of the light spectrum with orange lens glasses (blue blockers) would prevent the light‐induced melatonin suppression was tested, a test broadly used as an indirect assessment of the circadian clock sensitivity.
Dark therapy for bipolar disorder using amber lenses for blue light blockade.
Blocking low-wavelength light prevents nocturnal melatonin suppression with no adverse effect on performance during simulated shift work.
Normalization of endogenous melatonin production while wearing goggles did not impair measures of performance, subjective sleepiness, or alertness, and all subjects demonstrated preserved melatonin levels in filtered light similar to their dim-light secretion profile.
Safety considerations for the use of blue‐light blocking glasses in shift‐workers
  • S. Lockley
  • Psychology
    Journal of pineal research
  • 2007
While blocking blue-light exposure for shift-workers during the morning may be desirable from the perspective of circadian rhythm adaptation, short-wavelength light also directly enhances alertness and therefore use of these glasses while driving may introduce a more immediate safety hazard and increase the risk of shift- workers having a fatigue-related crash during their commute home.
Light‐Induced Melatonin Suppression in Humans with Polychromatic and Monochromatic Light
A stimulatory effect of the additional wavelengths of light present in the polychromatic light, which could be mediated via the stimulation of cone photopigments and/or melanopsin regeneration is suggested.
High‐intensity red light suppresses melatonin
The aims of the following studies were to test the efficacy of monochromatic light above 600 nm for melatonin suppression in hamsters and humans, and the possible roles of classical visual photoreceptors and the recently discovered intrinsically photosensitive retinal ganglion cells for circadian phototransduction.
Action Spectrum for Melatonin Regulation in Humans: Evidence for a Novel Circadian Photoreceptor
The results suggest that, in humans, a single photopigment may be primarily responsible for melatonin suppression, and its peak absorbance appears to be distinct from that of rod and cone cellphotopigments for vision.
Abnormal dose-response melatonin suppression by light in bipolar type I patients compared with healthy adult subjects
This study provides further evidence for a super sensitive response in bipolar I patients and suggests that its potential usefulness as an endophenotypic marker of the illness is deserving of further research.
An action spectrum for melatonin suppression: evidence for a novel non‐rod, non‐cone photoreceptor system in humans
The data strongly support a primary role for a novel short‐wavelength photopigment in light‐induced melatonin suppression and provide the first direct evidence of a non‐rod, non‐cone photoreceptive system in humans.