If colonics are so good, why haven't I heard about them before?

In a way, the answer to that is a commentary on our present day lifestyle. Historically, artifacts and records show that people have regularly purified their bodies, including cleansing the colon. Around the turn of the 20th century, the present-day colonic machine was developed, providing a significantly improved method of accomplishing colon cleansing. Up to the late 1920's many doctors had colonic machines in their offices, and machines were found in hospitals as well.
Articles dealing with colon health frequently appeared in prestigious medical and scientific journals until the early 1930's. At that time modern man began a 50-year love affair with drugs and surgery. These seemed to offer relatively instant relief for body ailments, resulting in purification and prevention techniques becoming less attractive. Recently, however, there has been a resurgence of interest in using natural approaches for healing the body, and colonics have rapidly been regaining the respectability they have already earned.