Goodmorning all,
we hope you had slept well last night!
Maybe it could be better, we know it, but now just a question: “at what time did you switch off pc/mac/tablet/smartphone and you started looking some non-blue-light-emitting surface?”

Many are sceptics and think this “belief” of Circadian rhythm and blue lights are¬†things for scientists or just a new business. But this is not!
Blue-light-emitting surfaces are actually affecting our hormone production. In particular, this kind of lights are unbalancing our production boosting cortisol hormone and suppressing melatonin.
These two hormones are the so-called antagonist, so one suppresses the effect of the other and their secretion is rhythmically driven in quantity by the brain.

  • Cortisol is the hormone which keeps you alerted, reactive and sometimes if present in too high quantities: stressed!

  • Melatonin has both a soporific effect and an ability to catch the sleep-wake rhythm. Melatonin treatment has been reported to be effective in the treatment of disorders such as jet lag and delayed sleep phase syndrome.

In this post we suggest to install onto your pc/mac/tablets/smartphones the following add-on software which it will help you to mitigate this unbalance effects. The blogger did it with very satisfactory results.

This software name is: f.lux




picture #1:  f.lux logo

f.lux¬†is a¬†cross-platform¬†computer program¬†that adjusts a¬†display’s¬†colour temperature¬†according to location and time of day. The program was designed to reduce¬†eye strain¬†during night-time use and reduce disruption of¬†sleep patterns.

f.lux proponents hypothesize that altering the colour temperature of a display to reduce the prominence of white‚Äďblue light at night will improve the effectiveness of sleep. This software is totally free: important to say!




Picture #2: half of the screen filtered with f.lux and half not


Reducing exposure to blue light at night time has been linked to increased melatonin secretion and better sleep quality.
Although the developer provides a list of relevant research on their website, the program itself has not been scientifically tested to determine its efficacy.
In spite of this, f.lux has been widely and positively reviewed by technology journalists, bloggers, and users.

Have a try on it, it doesn’t cost a dime and won’t harm your computer, it will help you instead to reach your bed more relaxed and ready to sleep!

Picture #3: clicking on the small icon on the taskbar you will be able to have a look onto your supposed cortisol-melatonin balance during the day.

Blue lights simply delay your natural sleep-time!
Today is possible to preview the side effects of this exposure calculating it on the basis of data such as:

  • date

  • time of the day

  • age

  • distance from the screen

  • type of light source

You have here different blue-light quantities present in the normal daylight cycle, in an electronic device screen and in a candle.

The same software producer, give you the possibility to meter the blue-light emitted from your device, have yourself a look here:!id=lights/candle&age=35

for further information about the subject, you can refer to another desk study done on Circadian rhythm done in this blog.



and goodnight !







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