A human's small intestine has its natural way of combating pathogens. However, with the presence of a food additive found in usual junk foods, the titanium dioxide, it decreases this natural ability of the small intestine.
In an ongoing attempt to boost the dwindling number of pandas on the planet (currently tallying just under 2,000), scientists have discovered what appears to be a physiological roadblock to the bear's good health: they possess the wrong type of gut.