The intestine is the seven meters long part of the digestive tract between the stomach and the anus. Made of the small intestine and the large intestine, it serves to the digestion and the assimilation of the nutrients from food, then to the elimination of the useless waste material. But, far from being a simple sewage duct, our intestine constantly communicates with the brain through the vagus nerve. Contrary to popular belief, the brain is not the sole organ blessed with neurons, far from it. There are some two hundred millions neurons in the digestive tract, hence its designation as our ‘second brain’.