Probiotics: What are they and exactly what can they do for you? Probiotics are various strains of “good” bacteria that are normally found throughout your body, especially in your digestive tract. There have been numerous research articles published recently on how these “good” bacteria can help with many of the aliments that are plaguing America today, such as irritable bowel syndrome, intestinal infections, cold and flu, eczema and even vaginal and urinary tract infections. Probiotics have also been shown to improve your immunity and help you recover faster from infections.