Prebiotics and Probiotics: Facts, Uses, and Gut Health
Author: Disabled World (DW)
Updated/Revised Date: 4 Aug 2026
Table of Contents:
Synopsis - Definition - About This Section - FAQs - Publications - Subtopics
Synopsis
Learn how prebiotics and probiotics support digestive and gut health, the difference between them, food sources, supplement uses, and what research shows.
At a Glance
- 1 - Lactobacillus is one of the most common probiotics used today.
- 2 - The human gut hosts roughly 400 to 500 types of microbes across its regions.
- 3 - Prebiotics are indigestible plant fibers found in onions, garlic, bananas, and artichokes.
- 4 - Fruit juices, such as a red-fruits mix, may serve as stable nondairy carriers for certain probiotic strains.
Topic Definition
- Prebiotics and Probiotics
Prebiotics and probiotics are two complementary components that support the balance of bacteria living in the human digestive system. Prebiotics are specialized plant fibers, a form of carbohydrate that the body cannot digest, and they act as food for the friendly bacteria already present in the gut. Probiotics, by contrast, are live microorganisms - mainly bacteria and yeasts - that, when taken in adequate amounts, can add to those beneficial populations and confer a health benefit on the host. Together they help nourish and maintain the gut microbiome, and both can be found naturally in foods such as whole grains, bananas, yogurt, and sauerkraut, or taken as dietary supplements.
Overview
Defining Prebiotic and Probiotic Difference
Prebiotics: Prebiotics are a form of dietary fiber that feed friendly bacteria in your digestive system. Prebiotics are special plant fibers that help healthy bacteria grow in your gut. This makes your digestive system work better by allowing your gut bacteria to produce nutrients for your colon cells, which leads to a healthier digestive system. Prebiotics come from types of carbohydrates (sugars, starches, and fibers found in fruits, grains, vegetables, and milk products) but mainly fiber that humans can't digest. The beneficial bacteria in your digestive system eat this fiber. Prebiotics can be obtained from foods such as onions, garlic, soybeans, whole grains, bananas, greens, and artichokes. In addition, probiotics and prebiotics are added to some foods and are also available as dietary supplements.
Probiotics: Probiotics are tiny living microorganisms, including bacteria and yeast, found in some foods or supplements that provide health benefits. The World Health Organization (WHO) defines probiotics as "live microorganisms which when administered in adequate amounts confer a health benefit on the host." Probiotics are part of a bigger picture concerning bacteria and your body - namely your microbiome. Live probiotic cultures are part of fermented dairy products, other fermented foods, and probiotic-fortified foods and can be obtained from foods such as yogurt and sauerkraut. Lactobacillus is one of the most common probiotics.
You don't necessarily need probiotics, foods, or supplements that contain "good" bacteria, to be healthy. However, these microorganisms may help with digestion and offer protection from harmful bacteria, just as the existing "good" bacteria in your body already do.
At the start of the 20th century, probiotics were thought to beneficially affect the host by improving its intestinal microbial balance, thus inhibiting pathogens and toxin producing bacteria. Today, specific health effects are being investigated and documented including alleviation of chronic intestinal inflammatory diseases, prevention, and treatment of pathogen-induced diarrhea, urogenital infections, and atopic diseases.
Probiotics are live microorganisms thought to be healthy for the host organism. According to the currently adopted definition by FAO/WHO, probiotics are: "Live microorganisms which when administered in adequate amounts confer a health benefit on the host".
Lactic acid bacteria (LAB) and bifidobacteria are the most common types of microbes used as probiotics, but certain yeasts and bacilli may also be helpful. Probiotics are commonly consumed as part of fermented foods with specially added active live cultures; such as in yogurt, soy yogurt, or as dietary supplements.
Experiments into the benefits of probiotic therapies suggest a range of potentially beneficial medicinal uses for probiotics. For many of the potential benefits, research is limited, and only preliminary results are available. It should be noted that the effects described are not general effects of probiotics. Recent research on the molecular biology and genomics of Lactobacillus has focused on the interaction with the immune system, anti-cancer potential, and potential as a biotherapeutic agent in cases of antibiotic-associated diarrhea, travelers' diarrhea, pediatric diarrhea, inflammatory bowel disease and irritable bowel syndrome.
Research is emerging on the potential health benefits of multiple probiotic strains as a health supplement rather than a single strain. The human gut is home to some 400-500 types of microbes. It is thought that this diverse environment may benefit from multiple probiotic strains; different strains populate different areas of the digestive tract, and studies are beginning to link different probiotic strains to specific health benefits.
Probiotics Added to Fruit Juice
Probiotics are often added to products to provide additional nutritional benefits to the consumer, thus making them "functional foods." A new study in the Journal of Food Science, published by the Institute of Food Technologists (IFT), found that fruit juices could potentially be good carriers for two different kinds of probiotics. The study found that certain strains of probiotics are stable in a fruit juice, namely a mix of red-fruits, and doesn't affect the sensory score.
Currently, most probiotic foods are dairy-based, but there is a growing interest toward nondairy probiotic products because of lactose intolerance and cholesterol content. Fruit juices are appealing due to their high content of beneficial nutrients like minerals, vitamins, dietary fibers, and antioxidants, and with additional research, could become a good source of probiotics as well.
Probiotics: Facts, Contradictions and Studies
- There is no good evidence taking probiotics helps maintain remission from ulcerative colitis.
- Some probiotics have been shown in preliminary research to possibly treat various forms of gastroenteritis.
- In some situations, such as where the person consuming probiotics is critically ill, probiotics could be harmful.
- Some of the best evidence supporting probiotic health benefits is in the treatment of antibiotic-associated diarrhea (AAD).
- A Cochrane Collaboration systematic review of the use of probiotics to treat acute infectious diarrhea found encouraging results.
- Ingestion of certain active strains may help lactose-intolerant individuals tolerate more lactose than they would otherwise have tolerated.
- Some studies have indicated that consumption of milk fermented with various strains of LAB may result in modest reductions in blood pressure.
- Preliminary human and animal studies have demonstrated the efficacy of some strains of lactic acid bacteria for reducing serum cholesterol levels.
- There is some evidence that probiotics may help people with irritable bowel syndrome, although uncertainty remains around which type of probiotic works best.
- A 2013 meta-analysis of 25 trials found that probiotic supplementation in pregnancy and early life might help with atopic sensitivity in infants, but probably not with asthma or wheezing.
- A 2010 study suggested that probiotics, by introducing "good" bacteria into the gut, may help maintain immune system activity, which in turn helps the body react more quickly to new infections.
More research is needed, but there is encouraging evidence probiotics may also help:
- Treat irritable bowel syndrome
- Prevent or reduce the severity of colds and flu
- Speed treatment of certain intestinal infections
- Treat diarrhea, especially following treatment with certain antibiotics
- Prevent and treat vaginal yeast infections and urinary tract infections
NOTE: Studies on the medical benefits of probiotics have yet to reveal a cause-effect relationship, and their medical effectiveness has yet to be conclusively proven for most of the studies conducted thus far.
Frequently Asked Questions
Are prebiotics and probiotics safe to take together
Yes, they are often taken together and are commonly called synbiotics because prebiotics act as food that helps probiotic bacteria survive and grow in the gut.
Can you get enough prebiotics and probiotics from food alone
Many people can meet their needs through a varied diet that includes fiber-rich plants and fermented foods, though supplements may help those with specific dietary limits or health goals.
How long does it take for probiotics to work
It varies by strain and purpose, but some people notice digestive changes within a few days to a few weeks, while other benefits may take longer and depend on consistent daily use.
Do probiotics need to be refrigerated
Some live probiotic products require refrigeration to keep the bacteria viable, while others are shelf stable, so it is best to follow the storage directions printed on the label.
Can antibiotics affect probiotic bacteria
Antibiotics can reduce both harmful and beneficial bacteria, which is why some people take probiotics during or after a course of antibiotics to help restore gut balance.
Are prebiotics and probiotics suitable for children
Both are present in many everyday foods that children eat, but parents should consult a pediatrician before giving concentrated supplements to infants or young children.
What is the difference between probiotics and fermented foods
Fermented foods are made using microbial cultures, but only those containing adequate amounts of specific live and beneficial strains are considered true probiotic foods.
Curated and edited by Ian C. Langtree, Founder & Editor-in-Chief, Disabled World. This section is maintained by the Disabled World editorial team.
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