Still useful after all these years: The appendix

Source: Adventures in Honduras

You can live without an appendix, true, but you should no longer think of this “vestigial” organ as a useless part of your anatomy. The appendix is finally getting the respect it deserves.
We have ten times as many bacteria in the body as we have cells (and we have 10,000,000,000,000 cells). The human digestive system runs on bacteria, where they’re called gut flora. The appendix turns out to be a storage container for the beneficial bacteria that digest our food. When an illness such as cholera empties the contents of the digestive track too rapidly, we lose bacteria. The appendix reboots the digestive track by repopulating the intestines with the bacteria stored in its little pouch.

The downside of an overly hygienic society

Why did it take so long to appreciate the appendix? “It’s hard to figure out what the appendix does when you’re studying superclean animals and people,” according to Bill Parker, a Duke professor of surgery. The appendix evolved when lifestyles were much dirtier and were plagued with parasites. People got sick with diarrheal diseases much more often.

Also, if you lose your intestinal bacteria in a modern industrialized society, you can easily repopulate your system simply by interacting with other people. (Not a pretty thought, I know.) When living conditions were less dense, and when whole geographical regions could suffer from a disease such as cholera, it was not as easy to acquire beneficial bacteria from fellow citizens.
Less developed countries have a much lower incidence of appendicitis than the US. According to Parker, “[T]he appendix may be another case of an overly hygienic society triggering an overreaction by the body’s immune system.”

The appendectomy in medical history

The inside of the human body is a sterile environment (not the digestive tract, of course, which is simply a passageway through the body). It’s important to remove the appendix if it becomes inflamed. A burst appendix can infect the abdominal cavity.
Surgery for appendicitis was not really practical before antisepsis (1860s) and anesthesia (1840s). The treatment for appendicitis was “wait and see,” which was often fatal. After a 1913 scientific study demonstrated that survival rates were better with surgery, the appendectomy became a more common surgical procedure.
It was so common, in fact, that appendectomies for “chronic” appendicitis – repeated pain that went away on its own – became fashionable in the 1920s and 1930s. Appendectomies played a role in the transition from the avoidance of medical procedures to the social acceptance of modern surgery.
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