The Center for Disease Control (CDC) conducts an ongoing telephone survey of medical problems and health care utilization – called the National Health Interview Survey (NHIS). They recently released their data from 2007. This is the first year for which they specifically broke out questions assessing the use of so-called complementary and alternative medicine (CAM).
CAM is a political/ideological entity, not a scientific one. It is an artificial category created for the purpose of promoting a diverse set of dubious, untested, or fraudulent health practices. It is an excellent example of the (successful) use of language as a propaganda tool.
The fundamental intellectual flaw of “CAM” as a concept is that it is made to include modalities that are extremely diverse, even mutually contradictory, under one umbrella. Very deliberately modalities which are scientific and mainstream, like the proper use of nutrition, are often included under the CAM umbrella by proponents in order to make it seem like CAM is a bigger phenomenon than it actually is, and as a wedge to open the door for the more pseudoscientific modalities.