In China, internet addiction is a very real problem. via Netscape with CNN:

“All the children here have left school because they are playing games or in chat rooms everyday,” says the clinic’s director, Dr. Tao Ran. “They are suffering from depression, nervousness, fear and unwillingness to interact with others, panic and agitation. They also have sleep disorders, the shakes and numbness in their hands.”

Nothing in excess, whether it be sleeping, eating, working or yes, even the internet, is healthy.