The Global Darkness Shortage
Darkness advocates say that constant exposure to light sources -- whether they be from the inside or outside -- disrupts sleep cycles and causes physical stress. They even discourage the use of night lights, arguing that the human body evolved in environments where nighttime meant absolute darkness. Scientists are conducting studies to see whether exposure to nighttime light can suppress the body's production of melatonin, an enzyme believed to aid in fighting diseases such as cancer.
Sources: Taipei Times, Boing Boing