One should also note that a vegetarian diet may not be optimal for your individual health profile. People with colitis, diversticulitis, chron's disease / IBS or other allergies might not do well on a high fiber diet. In other words, there's a lot of debate still about which diets are optimal for humans. Clearly there's a spectrum, but a vegetarian diet or a vegan diet may not be the most healthy diet for a given individual.