Endotoxin is involved in most diseases
"The intestine is source of toxins, and some studies have found considerable life extension by keeping the intestine free of bacteria. At the beginning of the 20th century, Elie Metchnikof (The Nature of Man, 1894, Prolongation of Life; Optimistic Studies,1907) believed, basing his ideas on comparative biology, that intestinal toxins caused aging by disrupting the immune and endocrine systems’ functions in tissue maintenance and renewal. He noticed that the intestine of short-lived herbivore such as rabbits had a strong odor of putrefaction and a great variety of bacterial species, but that the intestines of long-lived birds such as parrots and ravens had no unpleasant smell, even when he had fed the ravens with rotting meat, and contained only a few species of bacteria.