Prebiotics and Probiotics

Our intestinal tract is filled with many different microorganisms that contribute to digestion, immune health, and overall well-being. These microorganisms in our gut even outnumber the cells in our body! The amount and types of microorganisms look different in everyone. Lifestyle changes to our diet, environment, stress, and medications like antibiotics can change the diversity of these microorganisms in our gut. A drastic change in gut microbiota can result in uncomfortable changes to our body like diarrhea, constipation, or even contribute to certain diseases. Luckily there are ways to maintain a healthy gut.  


Probiotics in food or that you buy as a supplement are live microorganisms, similar to those within our intestinal tract, that can be consumed to offer health benefits. Research is currently looking into probiotics as a treatment option for gastrointestinal diseases, obesity, insulin resistance syndrome, type 2 diabetes, and non-alcoholic fatty liver disease. Probiotics work by helping to restore the good bacteria in our gut and fighting the harmful bacteria.  
For a probiotic to work, it needs to be alive when it reaches the stomach. Cooking methods like heating will kill the probiotics. The outcome of probiotics depends on the amount and type consumed. Probiotics can be consumed via capsules, tablets, drops, sachets, or sticks.  

To check for the amount and probiotic type, look at the food or supplement label name and number. Examples of probiotic names known to offer health benefits include species starting with the name Bifidobacterium and Lactobacillus. The label should consist of the name followed by a number usually ending in CFU, the unit used to list the specific amount. Anything over 1 billion or 1 x 109 CFU is big enough to offer health benefits. For example, a label might say Lactobacillus Acidophilus 1 billion CFU.   

Do Certain Foods Contain Probiotics?   

Yogurt is a popular food that many people believe to contain probiotics. Surprisingly, not all yogurts contain live cultures of probiotics. Even though yogurt is made from live bacteria, it may not still have it when packaged. To see if your yogurt contains probiotics, check the label for the bacteria species name and number. Fermented foods like sauerkraut also offer health benefits, but scientists are unsure if the food itself provides health benefits or the microbes used to make them do. Kombucha, a recently popular beverage, is also fermented from microbes and usually does contain probiotics. To double-check if your fermented foods contain microbes, check the label to ensure both the bacterial species and amount in CFUs are listed.  


Prebiotics are the “food” for the bacteria in our gut that our body cannot digest, but our gut bacteria can. The fiber from our foods found in whole grains, vegetables, and fruits also act as “food” for our gut bacteria. Bacteria use fermentation, which is when bacteria “eat” prebiotics and fiber to make short-chain fatty acids. Our body then uses short-chain fatty acids for other biological processes like keeping our gut lining healthy and gut-brain communication in check. Overall, prebiotics work by stimulating the growth or activity of a particular type of microorganism in our gut. All types of prebiotics can be considered as fiber, but not all fiber can be considered as prebiotics. The best way to keep a healthy gut and “feed” our gut microbiota is to eat various fruits and vegetables and avoid processed foods.

Benefits of Probiotics and Prebiotics:  

Probiotics help our intestinal tract fight off pathogens, also known as the “bad” bacteria, which support our overall immune health. Many probiotics are also involved in helping our body make vitamins that are essential for overall health and bodily functions. For example, the enzymes in our body that use vitamin B12 are made by our gut bacteria. Vitamin B12 is vital for nerve function, red blood cells, and DNA function. While probiotics provide our body with good bacteria, prebiotics keeps our good bacteria going. 



Military Family Network: Enhancing Health and Wellness with Probiotics Webinar 

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Paulina Markowiak and Katarzyna Slizewska Effects of Probiotics, Prebiotics, and Synbiotics on Human Health  

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Micael J Morowitz, MD, Erica Carlisle, MD, and John C. Alverdy, MD. Contributions of Intestinal Bacteria to Nutrition and Metabolism in the Critically Ill. DOI: 10.1016/j.suc.2011.05.001