The Difference Between Probiotics & Prebiotics

Probiotic and prebiotic foods and supplements enhance the growth of healthy microorganisms in your body. The idea of using bacteria to improve human health has been around since the early 1900s, but the general public did not fully embrace the concept until recently. Today, probiotic and prebiotic products are used widely, most often in the treatment and prevention of gastrointestinal conditions.

Good Bacteria

Your body contains billions of bacteria that help you stay healthy. The largest population of bacteria can be found in your intestines. These beneficial bacteria help you digest food, and without them you could not obtain vitamin K from your food. If the community of bacteria in your intestines is disrupted you may experience digestive difficulties and gastrointestinal symptoms. In order to re-establish healthy intestinal bacteria you can take probiotic or prebiotic supplements.


Probiotics are live microorganisms that can positively impact your health, according to the World Health Organization. Microorganisms are tiny animals made of a single cell. While most probiotics are bacteria, there are also strains of yeast that benefit your body. You can find probiotics in many food products, including fermented dairy and soy products. Probiotics can also be purchased in supplement form. The bacteria and yeast in probiotic products are well-studied strains that have been specially prepared to survive the journey through the stomach into the intestines where they can grow.


Prebiotics are substances that encourage the growth of beneficial bacteria—you can think of prebiotics as food for probiotics and the healthy bacteria in your system. Whereas probiotics are living microorganisms, prebiotics are non-living. Most prebiotics are carbohydrates that the human body cannot digest but which make excellent food sources for beneficial bacteria. Prebiotics can encourage the growth of beneficial bacteria already living in the body and also aid in the growth and maintenance of probiotics.


The combination of probiotic and prebiotic therapies is referred to as synbiotics. The strategy of combining a probiotic with its preferred nutrient may allow for probiotics to stay present in your body for longer, according to a May 1999 article in the "American Journal of Clinical Nutrition." Synbiotic therapies are relatively new and are the focus of many studies to determine their efficacy 3.


Probiotics and prebiotics have similar health benefits because they both accomplish the goal of increasing the population of healthy bacteria and yeast in your body. Healthy bacteria can form a protective shield in your digestive tract that prevents harmful bacteria and viruses from infecting your body, according to an April 2005 article in "FEMS Microbiology Ecology." The presence of healthy bacteria can also keep your immune system "primed" and ready to respond to a threat. Probiotics and prebiotics are particularly useful in replenishing healthy bacteria communities after a disruption such as an infection or antibiotic use.