According to OSHA on November 19, 1999,
Computer vision syndrome (CVS), defined as a complex of eye and vision problems that are experienced during and related to computer use, is a repetitive strain disorder that appears to be growing rapidly, with some studies estimating that 90 percent of the 70 million U.S. workers using computers for more than 3 hours per day experience it (CVS) in some form.
The use of computers in the United States and the world is growing exponentially. The amount of time one spends looking at a computer screen is also increasing similarly. Humans evolved biologically as hunters and gatherers. Our vision developed primarily for seeing distance (98% of all humans are born farsighted). Our eye muscle systems are in their most relaxed state when we use our vision for distance objects and space. In similar fashion, our bodies were designed for movement. Maintaining a sitting posture for long periods of time is unnatural for us.
As a result, working at a computer for a long period of time without breaks can cause unnatural strain on us that can result in a condition called computer fatigue syndrome. Computer users have shown to have a reduced average blinking time while using computers, which, according to Japanese investigators, causes a major risk of developing transient, or short-term dry eyes.
Over a period of time, excessive computer use can have cumulative negative effects on the user including the worsening of farsightedness, nearsightedness, astigmatism, eye-focusing disorders and poor eye coordination. In addition, constant working from a set position can cause neck and shoulder stiffness, as well as stress headaches, which can then cause pain in the jaw (referred to TMJ or temporomandibular joint).
