Till we turn 75 years old our intestine has been deviding around 30 tones of food and 50,000 liters of liquid into nutrients. It needs around 20 hours to fully digest the things we consume. In the small intestine the food is being devided into nutrients, vitamins and minerals. These travel through the intestinal wall into our body. The remains get to the colon, where water gets extracted before they are finally excreted in the rectum.