Are blue light filters useful?

In 2017 the Nobel Prize in Medicine and Physiology to three chronobiologists who worked on the molecular mechanisms of circadian rhythms. Jeffrey C. Hall, Michael Rosbash and Michael W. Young secured the prestigious award with research results from 1984 and 1994.
This sounds like material for Günther Jauch and “Who Wants to Be a Millionaire”. However, the following text explains to what extent this topic every person is concerned and like you Bring control to your circadian rhythm with a simple tool and what role blue light filters play.

Internal clock – the circadian rhythm

The circadian rhythm refers to our internal clock and thus all processes that guide us in a Rhythm of 24 hours (circadian = about one day). Processes such as eating habits, body temperature, sleeping habits and hormone regulation play an important role. Above all, the release of the hormone melatonin from the pineal gland is significantly involved in sleep-wake regulation. The effects of our daily rhythm are evolutionarily anchored in us and have offered a survival advantage over millions of years through permanent adaptation to external living conditions.

Light and melatonin levels

Our body is excellently able to react to light. When it gets darker, more Melatonin which promotes sleep and subsequently makes us tired. You notice this particularly well when the season changes from a long, bright day to a short, dark day. In autumn and winter, you certainly feel tired more often than in summer, which can be explained physiologically simply: your body releases melatonin earlier.

Another example is the Jet lag after a long flight with a change of time zones. Here too, the internal clock plays an important role. Due to the time shift, the body is either kept "unnaturally" awake by longer exposure to light, or melatonin is released earlier because it is already dark there.

Increasing screen time

According to a survey from the USA, adult Americans look at a screen almost eleven hours a day. In Germany, according to a Bitkom survey, the figure is currently around ten hours.

Why are we telling you this? Due to the increased use of digital work, many people's screen time has increased dramatically in recent decades. The Corona pandemic has accelerated this trend even further. This increase also has effects on life that are not directly comprehensible. This means that screen light affects your circadian rhythm and keeps you awake longer in an unnatural way. The reason for this is the delayed or reduced release of melatonin.

Why does blue light prevent you from sleeping?

As explained at the beginning, our body reacts very sensitively to external lighting conditions. Light consists of a spectrum of different light colors, which together appear as white light: red, orange, yellow, green, blue and violet. Darker colors such as blue and violet have a short wavelength (nm) and high energy (eV): Blue 430-490 nm with about 2,65 eV and violet 380-430 nm with about 3,1 eV. Orange, on the other hand, has a long wavelength of 600-640nm and lower energy of about 2 eV.

The short wavelength and high energy make it easier for the light to penetrate our eyes through the cornea and lens, thereby causing a physical reaction. The high-energy blue light consequently minimizes our natural melatonin secretion. However, blue light is also found quite normally in daylight and has physiological effects on the body. After all, we are supposed to be and stay awake during the day.

The proportion of blue light is usually significantly higher in screens of any kind. The longer you look at screens in the evening, be it your smartphone or your television, the longer the release of melatonin is inhibited. This means that you have a harder time falling asleep. And as you have already learned, sleep is the most efficient and cheapest anti-aging program.

What options do you have if you still have to do some screen work in the evening or if you want to watch a film with friends?

Technical remedy – blue light filter glasses

A very useful tool has been Blue light filter glasses Depending on the filter, these are able to block blue light to varying degrees. They therefore ensure that your Melatonin secretion not so strongly inhibited The effects are also scientifically proven.

A study with college students tested the actual effectiveness of blue light filters using three different groups, all of whom sat in front of a monitor in the evening. One group sat in front of the monitor without glasses, one with Blue light filter glasses and a third group with glasses that block orange light. In all groups, the melatonin level was determined by means of a saliva test. The results were groundbreaking. The group that was only exposed to blue light had the lowest level of melatonin and the group with the blue light filter had the highest melatonin levels.

Other studies examined the Effect of blue light in the morning and here too they came to a result that supports the theory. Blue light in the morning makes you more alert, which the people tested could also subjectively perceive. So in order to get going more easily in the morning, daylight lamps prove to be helpful.

Furthermore, a New York study using blue light filters found that people who suffered from sleep disorders Insomnia and quality of life improved and stress levels decreased.

How to wear your blue light filter glasses correctly

For a natural release of melatonin and thus a good night's sleep, it is recommended to wear blue light filter glasses as soon as it gets dark outside. This way, your circadian rhythm is not disturbed and you can get up the next morning feeling refreshed and healthy.

There is now an overwhelming selection of blue light filter glasses available online. It is important to distinguish between the different filter levels. Glasses that block more than 99% of blue light have a significantly greater effect on the release of melatonin than glasses that only block 20%.

If you already wear optical glasses, then a so-called clip on be a cost-effective solution. You can easily put these on your existing glasses. Alternatively, specialist retailers also offer optical glasses with an integrated blue light filter.

Blue light filter glasses from PhotonPro

We personally tested the models BERLIN NIGHT and NEW YORK NIGHTfrom the German provider PhotonProThe glasses will be delivered to your home very quickly by post in an economical cardboard box. Delivery Included is a nice case, the glasses in an additional protective plastic cover and a branded cleaning cloth.

Test conclusion: In addition to one subjectively better sleep we had the feeling that the eyes were strained when working late at night not so stressed In addition, dry eyes are significantly less dependent on moisturizing than without a blue light filter. One disadvantage is the strong orange coloring of the image. This is rather irrelevant when working with office programs, can definitely limit the quality of a movie nightAlternative glasses with a lower filter effect are available here.