Probiotics are also known as 'good' or 'friendly' bacteria. They are the beneficial microorganisms that are found in the human body, especially the gastrointestinal tract, but also on the skin, in the vagina and elsewhere. Some estimates say that we actually have more probiotic bacteria in our systems than cells in our entire bodies! The proper balance of these can be thrown off very easily (known as dysbiosis), and this has been implicated in a number of conditions, from allergies to irritable bowel syndrome. Probiotic supplements may help to rebalance the levels of bacteria in the system, and in doing so, may assist in treating and managing certain conditions. Prebiotics are essentially 'food' for the good bacteria, and prebiotic supplementation can help the good bacteria to thrive in the gastrointestinal system