Medical Info Overload?

We recently ran a bleg about dealing with too much data.
That bleg prompted the following note from a reader named Geoff Barry:

I had a thought on when it can be truly negative — even unhealthy.
Too much medical information at a layman’s fingertips can actually be detrimental, both for the doctor treating the patient and for the patient himself. The body’s major presenting symptoms — headaches, body aches, sore throat, runny nose, etc. — often are part and parcel of many diseases. Medical sites like WebMD allow the patient to peruse, based on symptoms, what he may have.
Without an intervening specialist to aggregate everything the body is telling the patient, the patient can be led down the wrong path, develop anxiety around imaginary medical issues, or even demand that the doctor test him for something he thinks he may have. In an era of rising costs and a shrinking number of general practitioners, a more acutely aware patient public could turn out to be a bad thing, for the patient and for the industry.
Of course, I’m not negating the positive effects of this information — especially for those who have already been properly diagnosed. It can help family members understand diagnoses, limit disinformation, and lead the patient toward additional treatment alternatives. But as someone who has (more than once) hopped onto WebMD and been assaulted by a litany of disorders that I immediately began to exhibit (in my head) symptoms of, too much medical information can be a bad thing without a professional to sort through it with.

Geoff raises a bunch of points that we’ve touched on before, including the fact that doctors rarely use e-mail with patients and the pros and cons of patient social networks like iMedix.
But what it most reminded me of was a passage in a book by Thomas Gilovich called How We Know What Isn’t So: The Fallibility of Human Reason in Everyday Life. Here’s the section I’m thinking of (go to page 127), which discusses how patients (and doctors) are often really bad at figuring out what “cures” them because so often, illnesses “are self-limited — i.e., they are cured by the body’s own healing processes without assistance from medical science.”
One of Gilovich’s very good points is that people generally seek medical help when their symptoms are peaking — which, as it turns out, is right about the time the illness is retreating on its own.