Circadian Rhythms

Entrained by the body’s internal clock, circadian rhythms rule all aspects of our biology and behavior; they are basically our physiological and behavioral rhythms within a roughly 24-hour cycle. As many scientists in different fields are joining in unlocking the mysteries of circadian rhythms, it is widely understood that balancing this self-regulating mechanism is the key to our physiological and behavioral health.  


Biological Clock

A master clock located in our hypothalamus is the responsible conductor for synchronizing our complex circadian system. This timing mechanism helps to control body temperature, thirst, hunger and it is involved in sleep and emotional activities. 

To date, scientists have discovered five environmental cues that in a variety of ways sync our biological clocks and harmonize our biological rhythms with the natural environment and the day/night or light/dark daily cycles.These five environmental cues are:

  • Daylight, or more specifically the high energy visible light in the spectrum which appears blue. 

  • Mealtime or intake of calories at different times of the day. 

  • Physical activity with various intensities. 

  • Social interaction and communal life. 

  • The ambient temperature of the living environment and its daily oscillation.


Circadian Rhythms Disruption 

Scientific research indicates that six of the top ten causes of death in the industrial world are chronic and metabolic diseases strongly associated with sleep disorders and circadian rhythms disruption. Chronic and metabolic diseases include cardiovascular diseases, heart disease, stroke, chronic respiratory problems, high blood pressure, high blood cholesterol, diabetes, obesity, some cancers, gallbladder disease and gallbladder stone. In addition, some mental disorders such as depression, seasonal affective disorder or SAD, manic depression, ADHD (Attention Deficit Hyperactivity Disorder) are almost always associated with sleep disorders and circadian rhythms disruption. 

The light/dark cycle plays the most important role in resetting this biological clock to balance our circadian rhythms.

The Light/Dark Cycle

Alerted by the environment, our biological master clock synchronizes billions of biological clocks inside our body for a harmoniously orchestrated performance. The light/dark cycle plays the most important role in resetting this biological clock to balance our circadian rhythms. The daily cycle caused by the earth’s daily rotation around its own axis is detected through photo receptors in our eyes with a direct connection to our biological master clock. When day ends and night starts, our eyes interpret the minimal exposure of light, or the lack thereof, to be able to coordinate the body clock into the dark cycle.

Unfortunately, our photo receptors are not capable of distinguishing between the real daylight and the light emitted from artificial lighting. With the advent of electric lights and electronic screens, we have extended the day cycle or virtual day. Bright artificial light suppresses the production and secretion of melatonin which delays the onset of many of the night/dark rhythms, causing an internal disharmony between our biological rhythms.



With the advent of electric lights and electronic screens, we have extended the day cycle or virtual day.

Balancing Circadian Rhythms

Light regulation is the surest and most natural remedy for entraining the circadian rhythms and a great remedy for melatonin deficiency. To be able to fine-tune our circadian rhythms we need to balance the light/dark cycle. This means we need ample exposure to bright light during the daytime and must avoid light at night. When exposed to plenty of daylight, the light triggers the production and secretion of serotonin in the brain.  Serotonin is a mood-boosting neurotransmitter associated with feeling calm, alert and focused.

At nighttime, on the other hand, it is important to enable our body and mind to relax to be able to sleep and rejuvenate. The brain needs to be exposed to darkness to be able to secrete the sleep hormone melatonin. However, when exposed to electrical lights and electronic screens at night the brain gets ready for the daytime rhythm and suppresses the timely secretion of melatonin.



Virtual Darkness

Around the year 2000 scientists realized that it is the blue segment of the light spectrum which sends light/day time signals to the brain which prepares the body for the daytime rhythms. By eliminating the blue light, the brain starts the secretion of melatonin via pineal glands and sets the body and brain for the dark-/nighttime activities.

Multiple studies have shown when it is not possible to be in total darkness in the night time, it is possible to create a virtual darkness conditions by filtering out the blue light by using glasses with blue blocking lenses. The brain interprets lack of blue light as total darkness and starts secretion of melatonin and coordinates many night-time cycles. Filtering the blue light at night on a regular basis helps to regulate sleep and other night cycles to restore healthy and balanced physiological and behavioral events.



It is only the blue segment of the light spectrum which sends light/day time signals to the brain.  



Circadian Eyewear provides virtual darkness glasses which filter out the blue light while you still can perform your evening tasks using electronic screens and being exposed to electric lighting.

Numerous studies over the past 50 years have demonstrated the relationship between blue light and melatonin production. Research has proven wearing virtual darkness glasses by test subjects enabled them to produce melatonin as if they were kept in total darkness. The conclusion shows glasses blocking the blue wavelengths are able to help normalize melatonin production and help regulate sleep cycle, entrain circadian rhythms, and help with various health issues.

By wearing Circadian Eyewear about two hours before scheduled sleep time, one can still be active at night. Our finely tuned Orpheus lens blocks 99% of the blue light in order to send a signal to the brain to start the natural secretion of the sleep hormone melatonin and to set your body’s master clock to night mode and relaxation.

Circadian Eyewear can be used in many different contexts to adjust the body's circadian rhythms as a preventive measure or a treatment for: 

Sleep Disorders 
Weight Management 
Shift Work 
Athletic Recovery 
Jet Lag 
Aging & Dementia 
Postpartum Depression 
Bipolar Disorder 
SAD (Seasonal Affective Disorder) 
ADHD (Attention Deficit Hyperactivity) 

Circadian Eyewear Collection 





The field of circadian rhythms and the effect of light in our daily life and health is becoming a widely researched topic. The 2017 Nobel Prize in Physiology or Medicine went jointly to Jeffrey C. Hall, Michael Rosbash and Michael W. Young for their discoveries of molecular mechanisms controlling the circadian rhythms. You can find their press release here: 

Press release from Nobel Prize regarding discoveries of molecular mechanisms controlling the circadian rhythm

Video from Brigham and Women’s Hospital
Circadian Rhythms and Your Health Video - Brigham and Women's Hospital 

Research from PubMed
Does Current Scientific Evidence Support a Link Between Light at Night and Breast Cancer Among Female Night-Shift Nurses? 

Blue-blocking glasses as an additive treatment for mania: a randomized placebo-controlled trial 

Wearing blue light-blocking glasses in the evening advances circadian rhythms in the patients with delayed sleep phase disorder: An open-label trial  

Circadian Rhythm Sleep-Wake Disorders in Older Adults  

Melatonin as an endogenous regulator of diseases: The role of autophagy  

New perspectives on the role of melatonin in human sleep, circadian rhythms and their regulation 

Circadian Rhythm Abnormalities 

Links between Circadian Rhythms and Psychiatric Disease  

Influence of sleep-wake and circadian rhythm disturbances in psychiatric disorders 

Sleep and circadian rhythms in humans 

Research Sources

Wearing virtual darkness glasses by test subjects enabled them to produce melatonin as if they were kept in total darkness.