The blue light filter, which is often used to treat blue light sensitivity, is a device designed to prevent harmful blue light from reaching the human eye, but its use can cause harm if it is not properly adjusted.
The manufacturer claims that a filter with a blue light intensity of less than 0.2 milliwatts (milliwatts is the light level at which human beings experience discomfort).
According to the manufacturer, blue light has been shown to cause “a range of health problems including eye irritation, inflammation, skin changes, and skin cancer.”
However, a 2013 study published in the American Journal of Epidemiology found that there was “limited evidence to show that blue light is associated with an increased risk of skin cancer, including melanoma.”
A 2015 study by the University of Illinois, Urbana-Champaign, found that “the cumulative effect of blue light exposure may be as much as 10 times greater than previously thought.”
The researchers found that even with the best blue light filtering, people exposed to the light for only 10 hours a day could experience a reduction in skin sensitivity to blue light.
A 2014 study published by the American Academy of Dermatology found that exposure to blue lights for 10 hours or more “may increase skin sensitivity by an average of 10 percent.”
A 2017 review published in British Medical Journal found that blue-light filters are “not well tolerated and, in many instances, do not significantly improve skin health.”
The report concluded that “there is insufficient evidence to recommend that the use of blue-lights to treat light sensitivity is justified in patients.”
The National Institutes of Health recommends using blue-level filters “to reduce blue light” for patients with sunburn and sun sensitivity.
The American Academy’s report concluded, “Reducing the amount of blue in a room with sufficient light for human use is a well-known and well-studied practice.”
In a 2016 study published online in the Journal of Occupational and Environmental Medicine, researchers found “that the use a blue filter at the end of a white board or computer screen reduced the amount and quality of white light on that whiteboard by approximately one-half.”
A 2016 study in the International Journal of Environmental Research and Public Health found that using a blue-filtering filter to protect your eyes “does not significantly increase the risk of eye damage, irritation, or damage to skin.”
The U.S. Food and Drug Administration recommends using a filter that is 1 milliwatt (milliampere) or less.
A 2013 study by UCLA’s Institute of Medicine found that for children and young adults who had a skin sensitivity of “below normal,” the filter “did not reduce the severity of the skin sensitivity” and “had no effect on the development of skin inflammation.”
In other words, the filter may not be the best option.
The FDA recommends using filters with a “blue light intensity below 0.3 milliwawatts (millowatts is one millionth of a watt).”
The FDA says the recommended blue light filters are: A filter with no blue light (such as a filter made of polycarbonate or a blue ribbon) with a light intensity between 0.1 and 0.5 milliwats (milliamps) A filter that meets all of the following requirements: A 1 millimeter (0.2 inches) or greater diameter filter with an output of less then one milliwave (1 mW) that can be easily adjusted by the user without removing or changing the filter, and a light source that is brighter than the sun, the sun’s UV radiation, or a filter in the shade or indoors.
The U.K. government’s Institute for Advanced Materials recommends using filtered glass that “provides protection from harmful light by reflecting only a small portion of visible light, and is capable of reflecting sunlight in the UV range of light that causes damage to human skin.”
A 2009 review published online by the journal Photochemistry and Photobiology B concluded that blue filters “are the best choice” for protecting skin.
“The FDA and the manufacturers of blue filters state that they do not reduce human skin sensitivity,” the 2009 review concluded.
“However, many of the filters on the market are designed for a specific purpose, such as to reduce sunburn, or are designed to provide a ‘reduced’ or ‘no-reduction’ effect to protect eyes.”
A 2012 study published to the journal Nature Photonics found that some filter manufacturers used the term “reduced” or “no-cut” in their descriptions.
In that review, “reduction” was defined as a decrease in “skin sensitivity” of between 2 and 10 percent.
“No reduction” was described as a “reduce or no change” in skin health.
A 2010 study published on the Web site of the Royal College of Physicians found that many filters “do not provide a reduced effect on skin sensitivity.”
A 2013 report published in Photomed