Intestinal juice is a part of the larger digestive system. It is an integral part of digestion and is excreted into the small and large intestines when the body detects that there is food in the area. Intestinal juice serves several purposes. It helps to neutralize the acid coming in from the stomach. This protects the small and large intestines from becoming irritated. Intestinal juice contains digestive enzymes. These enzymes aid in the actual physical digestion of food and allow it to be absorbed by the body. Intestinal juice also sends gastrointestinal hormones out into the body through the bloodstream. These hormones, in turn, tell other parts of the body how to process the food once it is digested. Intestinal juice plays an important role in digestion, as it works to physically digest the food and to send out messages (through the release of hormones) instructing other systems in the body as to how to process the digested food.