When it comes to gut health, prebiotics and probiotics are two terms that often go hand-in-hand—but they refer to very different things. While they both play roles in maintaining a balanced gut environment, understanding what sets them apart can help clarify how they function in the digestive system and how they’re included in everyday products.

What Are Probiotics?

Probiotics are live microorganisms, often bacteria or yeasts, that are used in foods and dietary supplements. These microbes are typically added to products like yogurt, kefir, kombucha, and capsules with the goal of introducing specific strains into the digestive tract. Each probiotic strain—identified by its genus, species, and strain name—can behave differently. Common examples include Lactobacillus acidophilus, Bifidobacterium bifidum, and Saccharomyces boulardii.

What Are Prebiotics?

On the other hand, prebiotics are not living organisms. They are non-digestible fibers or carbohydrates that serve as nourishment for the microorganisms already living in the gut. Essentially, prebiotics act as a food source for beneficial bacteria. They pass through the upper part of the digestive tract without being broken down and are then fermented by microbes in the large intestine.

Where to Find Prebiotics

Prebiotics are commonly found in fiber-rich plant foods. Some well-known sources include garlic, onions, leeks, asparagus, bananas, oats, and Jerusalem artichokes. A particular type of fiber called inulin, found in chicory root, is often included in functional food and supplement products for its prebiotic properties.

Working Together: Synbiotics

Probiotics and prebiotics can be used separately, but they’re often combined in supplements or food products. When both are present, the product is sometimes referred to as synbiotic—a blend designed to support live microbes with compatible nourishment. While this term appears in some marketing materials and scientific literature, it’s important to understand that the effectiveness of such combinations can depend on many variables, including the specific strains used and the individual's existing microbiome.

Understanding the Complementary Roles

The relationship between prebiotics and probiotics is complementary. Just as garden plants benefit from the right soil and nutrients, probiotics may thrive when supported by the right prebiotic environment. Including a variety of fiber sources in the diet, or considering blends that contain both prebiotics and probiotics, is one way that people explore this balance in their everyday routines.

Clarifying the Terms

While probiotics introduce live cultures into the system, prebiotics focus on feeding what's already there. Understanding the difference helps demystify many of the labels and ingredient panels found in wellness products and supports more informed decision-making.

Both categories continue to be researched for their roles in digestive balance, and their inclusion in food and supplement products shows no sign of slowing down.

As always, talk to your doctor before taking any supplements. Get professional advice if you think you might need any supplement or are already taking one to ensure you’re not exceeding the amounts you may need.