Perhaps more important for our health than tuning our lighting during the day is to ensure we have correct lighting at the start and end of the day, eliminating light at night. Even the smallest amount of light spilling into our bedrooms at night can disrupt our sleep, so covering stand-by lights on televisions (which should be switched off anyway!) and covering gaps around doors are simple ways of reducing the amount of light we are exposed to while we sleep, complete darkness being required for melatonin to do its job. To engage the body's circadian rhythms, the hotel industry may lead the way in introducing lighting that gradually comes on to wake guests up more naturally and evening time lighting colours and intensities for the end of the day. The hope is that this will filter down to domestic lighting.
Read about the sleep expert who says light is the key to success in LUX Review online: http://bit.ly/2tt27mv