Taurine found in the RedBull drink and body building supplement will help repair the damage bright light carries out on your eyes, its also a nootropic helping users to lay down memories when they sleep, dream frequency including remembering dreams will also increase, dreaming is a sign that memories and learning is taking place amongst other things. Re no one showing a computer screen is harmful, the blue light from devices can keep people awake for longer including when using F.Lux, and the circadian rhythmes are such that it supresses the release of melatonin the sleep hormone which typically starts to rise from around 21:30 peaking around 01:30 before dropping off sharply. This time various depending on where you live in the world and day of the year as its link to sunset times. Melatonin is also 4x more potent as an anti-oxidant than Vitamin C and also helps increase the release of mesenchymal stem cells which aid the repair process carried out when we sleep. So yes studies have shown computer screens, smartphones used late in the evening and at night can cause damage to the body. Its not exclusively blue light which keeps people awake either, red light can also keep people alert, this is why vehicle brake lights are red, red being associated with danger which arouses the mind and body. One of the problems with the human body is it can also function adversely if expected light is missing from the light spectrum of the source. This will become more common place with the use of narrow band light sources like LED's when compared to the sun. The body has evolved over thousands of years in an environment which we are changing rapidly through technology and evolution can not keep up with man made changes.