Light is a major if not the biggest factor of the circadian rhythm and therefore is behind it’s regulation. Different spectrums of light produce different inputs to the circadian rhythm. Blue light interferes with the circadian rhythm’s natural regulation setting the circadian rhythm in it’s earlier stages. Exposure to blue light at or near night time is a big time disruptor of sleep quality. One of the mechanisms by which being suppressed melatonin secretion.
Red light on the other hand tends to be beneficial for the thyroid, testicles (in short durations), cellular energy production and more. Red light has a long wavelength making it the ideal light spectrum for night time.
Sources of blue light include artificial lighting such as lightbulbs and most notoriously electronics. Electronics usage before or around night time is very common with an emphasis in first world countries. This type of circadian rhythm disruption obviously ruins sleep quality and ends up making one sleepy during the day and possibly restless or wired around night time.
Needless to say the circadian rhythm disruption, decreased sleep quality and energy production, suppressed thyroid, among other downsides makes blue light anti-androgenic.
- From Harvard: Exposure to blue light at night produced by electronics and lightbulbs is harmful to health (1).
- Blue light may contribute to the causation of cancer, diabetes, heart disease, and obesity (1).
- An experiment done on 77 healthy university students using mobile phones tested T3, T4 and TSH levels. The experiment found a higher than normal TSH level, low mean T4 and normal T3 concentrations in mobile users compared to non-users. An increase in TSH following excessive use of mobile phones was recorded as well.
- Red light triples testicle function (1).
- Exposure to light-emitting e-readers at bedtime may negatively affect sleep and the circadian system (1).
- Some fluorescents and LEDs produce a blue-shifted spectrum, to which the human circadian system is most sensitive (1).
- American Medical Association issued a report cautioning against blue-rich LED streetlights, citing the detrimental effects on human health (1).
- Blue light is likely to cause the most disruption to sleep as it most effectively suppresses melatonin and increases alertness (1).
- More evidence on the negative effects of blue light (1) (2) (3) (4) (5) (6) (7) (8).
“Our eyes’ natural filters do not provide sufficient protection against blue light rays from the sun, let alone the blue light emanating from these devices or from blue light emitted from fluorescent-light tubes. Prolonged exposure to blue light may cause retinal damage and contribute to age-related macular degeneration, which can lead to loss of vision.” – source.
“Many of today’s electronic devices use LED back-light technology to help enhance screen brightness and clarity. These LEDs emit very strong blue light waves. Cell phones, computers, tablets and flat-screen televisions are just among a few of the devices that use this technology.” – source.
“Study after study has linked working the night shift and exposure to light at night to several types of cancer (breast, prostate), diabetes, heart disease, and obesity.” – source.
Blue light is problematic, good news is the solution is simple – blue light blocking glasses.
Worn at or around night time and especially when using electronics blue light blocking glasses filter out blue light and remove mostly all the effects of blue light.
Most if not all the blue light blocking glasses out on the market are made like plain unattractive reading/seeing glasses. This pair (here) have a stylish look without compromising on the lens quality and blue light blocking effect. As a matter of fact they are among the highest quality in terms of blue light blocking I could find.
- Blue light blocking glasses have been shown to reduce evening suppression of melatonin while viewing an LED computer screen (1).
- In one experiment participants who used blue light blocking lenses experienced significant improvement in sleep quality & significant improvements in mood compared to the control group.
- Wearing blue light blocking glasses in the evening advances circadian rhythms in patients with delayed sleep phase disorder (1).
- Blue light blocking glasses are effective as an add-on treatment for bipolar mania (1).
- Blue light blocking glasses have a significantly beneficial effect on the sleep quality of cataract patients (1).
The image below shows the significance blue light blocking glasses have on blue light emitted from iPads and likely other electronics.