(flickr/amers photos)

A new Pew survey found 35% of us like to play doctor and use the Internet to self diagnose our medical issues. The main reason we turn to the Internet first is to decide whether or not to consult a doctor. A third of us just handled it on our own.

This article states the obvious two dangers here --

A serious condition could go undetected and untreated
The Internet will often lead you to think you have a serious condition than is actually the case
Duh! You think it's a cold; the internet tells you it's a brain tumor. Thank you for the heart attack, Internet!