What is another name for a prebiotic?

November 22, 2025 •

4 min read

According to the International Scientific Association for Probiotics and Prebiotics (ISAPP), a prebiotic is a selectively fermented ingredient that results in specific changes in the composition and/or activity of the gastrointestinal microbiota, thus conferring benefits upon host health. In simple terms, another name for a prebiotic is a "microbiome fertilizer" because it nourishes the beneficial bacteria in your gut.

Quick Summary

A prebiotic can be called a 'microbiome fertilizer' as it selectively feeds beneficial bacteria in the gut. These specialized dietary fibers pass through the digestive system and are fermented by gut microbes, promoting the growth of healthy bacteria and yielding various health benefits.

Key Points

Microbiome Fertilizer: Another common name for a prebiotic is "microbiome fertilizer" because it serves as nourishment for the beneficial bacteria in your gut, helping them grow and thrive.
Prebiotics vs. Probiotics: Prebiotics are non-digestible food components, while probiotics are live microorganisms; prebiotics act as food for the probiotics.
Short-Chain Fatty Acids: When fermented by gut microbes, prebiotics produce beneficial short-chain fatty acids (SCFAs), which provide energy to colon cells and help regulate metabolism.
Common Types: Prebiotics come in various forms, including fructans (inulin), galacto-oligosaccharides (GOS), and resistant starches, all of which support digestive health.
Health Benefits: A diet rich in prebiotics can lead to improved digestion, enhanced immune function, better mineral absorption, and potential metabolic benefits like blood sugar control.
Natural Sources: Prebiotics are abundant in many whole foods, such as garlic, onions, bananas, asparagus, and legumes, making them easy to incorporate into your daily diet.

Understanding the 'Microbiome Fertilizer' Term

To fully grasp why "microbiome fertilizer" is an apt description for a prebiotic, it is helpful to consider the foundational relationship between prebiotics and the gut microbiome. Unlike probiotics, which introduce live beneficial bacteria to the gut, prebiotics are non-digestible compounds that serve as nourishment for the microorganisms already residing there. This process of feeding and cultivating the existing microbial population is similar to how a gardener uses fertilizer to enrich the soil, making the term a highly effective analogy. Prebiotics stimulate the growth and activity of specific, health-promoting bacteria, such as Bifidobacteria and Lactobacilli, thereby altering the composition of the gut microbiota in a favorable way.

How Prebiotics Function in the Gut

When you consume prebiotic-rich foods or supplements, they resist digestion in the stomach and small intestine, traveling intact to the large intestine. Here, the beneficial microorganisms ferment these compounds, a process that produces important byproducts known as short-chain fatty acids (SCFAs), including butyrate, acetate, and propionate. These SCFAs are crucial for several aspects of human health:

Butyrate: Acts as the primary energy source for the cells lining the colon, which helps maintain the integrity of the gut barrier.
Acetate and Propionate: Circulate through the bloodstream to influence other organs and systems, such as helping to regulate appetite and metabolism.
Lowered pH: The fermentation process also lowers the pH of the colon, which inhibits the growth of potentially harmful, acid-sensitive bacteria and promotes a healthier microbial balance.

These mechanisms demonstrate that prebiotics do far more than simply provide bulk; they actively participate in shaping the gut ecosystem and influencing overall health through the production of beneficial metabolites.

Different Types and Sources of Prebiotics

Prebiotics are not a single substance but a broad category of diverse compounds, most commonly dietary fibers and oligosaccharides. A wide variety of foods contain these naturally occurring "microbiome fertilizers," making it easy to incorporate them into a balanced diet.

Common Prebiotic Compounds

Fructans: Includes inulin and fructo-oligosaccharides (FOS). Rich sources include chicory root, garlic, onions, and asparagus.
Galacto-oligosaccharides (GOS): Found in legumes, such as beans and lentils, and some dairy products. GOS are also frequently added to infant formula to mimic the prebiotic content of breast milk.
Resistant Starch: A type of starch that resists digestion. Sources include unripe bananas, potatoes, and oats.
Pectin: A polysaccharide found in fruits like apples and berries.

Comparison of Common Prebiotics


Feature	Inulin	Galacto-oligosaccharides (GOS)	Resistant Starch	Pectin
Primary Source	Chicory root, garlic, onions	Legumes, beans, breast milk	Unripe bananas, potatoes	Apples, berries
Main Beneficial Bacteria	Bifidobacteria, Lactobacilli	Bifidobacteria, Lactobacilli	Bifidobacterium, Ruminococcus	Commensal bacteria, e.g., Faecalibacterium
SCFAs Produced	Butyrate, Propionate	Butyrate	Butyrate	Butyrate
Form	Supplement, food ingredient	Supplement, infant formula	Whole foods	Soluble fiber in foods

The Health Benefits of Prebiotics

The impact of prebiotics extends far beyond the gut, affecting several aspects of physical and mental health. By fostering a balanced and diverse microbiome, these compounds contribute to the production of crucial metabolic signals and immunomodulatory molecules.

Key Areas of Impact:

Digestive Health: Prebiotics can improve bowel regularity, relieve constipation, and enhance nutrient absorption, especially minerals like calcium. For some individuals, prebiotics may also help manage symptoms of inflammatory bowel disease (IBD).
Immune System Support: The gut and immune system have a close relationship. A healthy gut microbiome, stimulated by prebiotics, helps regulate immune function and decrease inflammatory responses.
Metabolic Regulation: Research suggests prebiotics can positively influence metabolic health markers. Studies have shown potential improvements in blood sugar control, lower cholesterol levels, and reduced body fat, particularly when combined with probiotics in synbiotic formulations.
Mental Well-being: The "gut-brain axis" highlights the connection between gut microbes and the nervous system. The SCFAs produced from prebiotic fermentation can influence neurotransmitters and brain function, potentially affecting mood, learning, and memory.

Optimizing Your Prebiotic Intake

For most people, the best way to increase prebiotic intake is through a diet rich in whole foods. Focusing on a variety of fruits, vegetables, legumes, and whole grains ensures you consume different types of prebiotics, which helps cultivate a more diverse and resilient gut microbiome. While supplements are available, they are not always necessary for healthy individuals who already consume a fiber-rich diet.

It is important to introduce prebiotic foods gradually to avoid potential digestive discomfort, such as gas or bloating. Starting with small, consistent portions can allow your digestive system to adapt. For individuals with existing gut sensitivities or conditions like IBS, it is always best to consult with a healthcare provider before making significant dietary changes or starting supplements.

Conclusion: More Than Just Fiber

While prebiotics are a type of dietary fiber, the name "microbiome fertilizer" offers a more descriptive and functional understanding of their role. They are not simply undigested food; they are powerful compounds that selectively nourish and stimulate the beneficial bacteria in your gut. By doing so, they initiate a cascade of positive effects throughout the body, from improving digestion and immunity to influencing metabolic and even cognitive health. Embracing a diet rich in prebiotic foods is a straightforward and effective strategy for nurturing your internal ecosystem and supporting long-term well-being. Understanding this key synonym helps emphasize the profound and active role these nutrients play in our health.

Visit Healthline for more detailed information on prebiotics and gut health.

Frequently Asked Questions

No, while all prebiotics are a type of dietary fiber, not all dietary fibers have prebiotic effects. A true prebiotic must be selectively fermented by beneficial gut bacteria in the large intestine and confer a health benefit.

For most healthy individuals who eat a balanced diet rich in fruits, vegetables, and whole grains, supplements are not necessary. Consuming a variety of prebiotic-rich foods is generally sufficient to support a healthy gut microbiome.

A synbiotic is a food or supplement that contains both prebiotics and probiotics. This combination is designed to improve the survival and effectiveness of the beneficial bacteria in the gut.

Yes, some people may experience mild side effects like gas, bloating, or abdominal discomfort, especially when first increasing their intake. Starting with smaller amounts and gradually increasing is recommended.

Prebiotics are non-digestible fibers that feed the good bacteria already in your gut, whereas probiotics are the actual live, beneficial microorganisms you introduce to your system, for instance through fermented foods like yogurt.

Some studies suggest that prebiotics, particularly when combined with probiotics, may aid in weight loss and fat loss. They can promote satiety and influence hormones related to appetite, but more research is ongoing.

Prebiotics enhance the growth of beneficial gut bacteria, which in turn helps regulate immune function. The short-chain fatty acids produced during fermentation also help maintain the intestinal lining and reduce inflammation.