These good bacteria (yeasts and bacteria) are also called Probiotics, and they live primarily in our guts. With over 75% of our immune system residing in our guts, its extremely important that we get our daily dose of these probiotics to keep everything functioning as is should. These organisms not only help aid digestion and alleviate symptoms of ulcerative colitis, irritable bowel syndrome (IBS) and diarrhea, but they are even beneficial for young children and infants with colic.