The probiotics, are the healthy bacteria that live inside the GI tract. These probiotics can also be taken in as a health supplement. Since the bacteria are colony forming in nature, once they reach the gut, they can multiply and increase the overall population of good bacteria in the gut. https://www.edocr.com/v/jn9l6olb/noreenmadeja92/Probiotic-Supplements-Select-the-Most-Appropriate-