Articulatory Loop

Another reason health care costs so much is that people (who are not doctors and have no medical training) go about demanding expensive procedures they think (often based on advertising) will do them some good. The current full-body-scan craze is a prime example.

First of all, the chances that it'll find anything in an asymptomatic patient (i.e., the kind getting these scans, because if they had symptoms a doctor could treat them) besides false-positives is very low. Second, in addition to not being helpful in diagnosing or treating cancer (what it's mostly billed as doing), it looks like it actually increases your risk! Is anyone surprised? Not really. I really like Chris Rangel's advice to the people to want these scans (since they're paying out of pocket):

Change over to magnetic resonance whole-body scanning. It may be more harmful to your wallet but it has no proven cancer risk and is just as useless as a screening exam. Have fun!

Now, since I just said people were paying out-of-pocket for this stuff, you're wondering why it makes health care more expensive for the rest of us? Here's how:

Mr. X goes to his doctor, and demands that he be given a full-body scan because *something* might be wrong with him. The doctor says no, but still bills for the visit. Since the doctor is Mr. X's GP, X pays his co-pay and insurance covers the rest. That's, say $100, out of the general pool of money.
Then, Mr. X goes to the body-scan guy on his own, and pays his own $2000 for it. And the scan guy finds ... something. Feeling vindicated, Mr. X goes back to his GP, who sends him on to a series of specialists to look at whatever the scan found. Most of the time, the scans find an artifact (a false positive), so Mr. X has just spent probably thousands of dollars of insurance money on specialist visits and more tests to prove that he does not have an illness no one thought he had in the first place.
The insurance pools have to be replenished from this, so the company raises premiums. Plus, he's increased his chances of actually getting cancer later on, which will cost even more!

Even if the scan finds a real tumor (which is very very rare), it's not likely that detecting it this way will have any effect on his treatment outcome, and thus he's still wasted all that money.