Probiotics, Prebiotics, and Synbiotics: Defining the Terms
The emerging importance of probiotics and their role in human health brings with it some potentially confusing terminology. This article aims to differentiate and define the most basic terms.
Probiotics: The good bacteria
The World Health Organization defines probiotics as “live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host.”
What that means is that probiotics, which can be found in food and taken as supplements, are bacteria that your body needs. Your digestive system is full of bacteria — good bacteria — that help your immune system, work to keep your digestive system healthy and efficient, and do numerous other positive things in your body. But bad bacteria, too, can get into your body, and if the bacteria balance get out of whack, probiotics add good bacteria back into your system.
You’ll find probiotics in fermented foods such as yogurts (with live, active cultures), sauerkraut, and kimchi. Keep in mind that most of the time, you can’t get enough probiotics through eating foods alone, and you’ll need to take a supplement.
Prebiotics: Fiber food for bacteria
Prebiotics are basically food for probiotics. Taking prebiotics helps probiotics work better and more efficiently. Prebiotics not digestible by humans, but they stimulate the growth of beneficial bacteria. Common prebiotics are inulin and carbohydrate fibers called oligosaccharides.
Prebiotics are found in fruits, vegetables, and whole grains. Prebiotics are an emerging field of study, and many researchers believe their potential to help you stay healthy may be as important as probiotics.
Synbiotics: Combining probiotics and prebiotics
A synbiotic is a supplement that contains both probiotics and prebiotics. It makes sense to make sure any supplement you take contains both pro- and prebiotics, because the two work in tandem to make sure your system has enough of the healthy, beneficial bacteria it needs.
Other probiotics terminology
CFUs: This stands for colony–forming unit and is the way probiotics are measured. You want to take a supplement with as many CFUs as you can find — in the 1 to 10 billion range.
Genus, species, and strain: These are how bacteria are identified. The genus is the first word in a bacterium’s name; it’s the large group to which the bacteria belongs. The species is the type of individual bacteria. Some bacteria have several strains, or differentiations of the species, and this is identified by the last part of the name. Here are a couple examples:
Lactobacillus rhamnosus (Lactobacillus is the genus, and rhamnosus is the species)
Lactobacillus acidophilus DDS-1 (Lactobacillus is the genus, acidophilus is the species; and DDS-1 is the strain)
Dysbiosis: This is the medical term for when the good and bad bacteria in your body get out of balance. Taking probiotics and prebiotics can help correct dysbiosis.