60-70% of the cells that make up your body are in the intestines—more cells in your digestive tract than there are in the entire rest of your body. And if the intestines are inflamed, so is the rest of your body. Most autoimmune diseases start in the intestines. The more inflammation you have in this area, the more likely it is that you’ll have problems elsewhere in the body. (You may also be amazed to hear that the combined length of your small and large intestines is about 25 ft!).