Home
Health Guides
Probiotic vs. Prebiotic: What Is the Difference?

A closeup of probiotics shown against a white background

Probiotic vs. Prebiotic: What Is the Difference?

Reviewed by: Trevor Kirby, PhD, Principal Research Scientist, Research

4 MIN READ — 6 Citations — 05/29/2026

There may only be one letter that distinguishes the two words, but there is a significant difference between prebiotics and probiotics. They play distinct, complementary roles in supporting your gut health and overall well-being.

Key Takeaways

01.
Probiotics are live, beneficial bacteria that support overall microbiome health. Prebiotics, on the other hand, are non-digestible fibers that feed the functioning of your beneficial gut bacteria.
02.
Unlike probiotics, prebiotics are not bacteria and do not add bacteria; They nourish the ones you already have.
03.
When probiotics and prebiotics are consumed together, they support a balanced microbiome.
04.
You can find prebiotics in a diverse, plant-rich diet, and fill gaps with supplements like AG1.

Together, probiotics and prebiotics support digestion, immune balance, and overall gut function when incorporated consistently into your daily diet. In this guide, we'll walk through why they both matter and how to get them both into your everyday routine.

What are probiotics?

Probiotics are living microorganisms (beneficial bacteria or yeasts) that support a balanced gut microbiota—helping digestive function while contributing to your immune health and your overall health.

Probiotics are found in a variety of fermented foods, including yogurt, kefir, sauerkraut, kimchi, miso, tempeh, kombucha, and apple cider vinegar (provided it contains “the mother,” which is the living culture of beneficial microorganisms). They’re also widely available in supplement form.

What are prebiotics?

Probiotics’ equally vital counterpart is prebiotics, indigestible food components (typically specific types of dietary fiber) that are able to pass through your upper gastrointestinal tract and reach your colon undisturbed, where they can undergo fermentation. This fermentation produces the short-chain fatty acids that help support gut lining integrity—and subsequent immune regulation, and overall digestive health.

Prebiotics are found in high-fiber plant foods, including onions, garlic, leeks, bananas, oats, asparagus, and legumes. Taking prebiotic supplements can be a useful option if your diet lacks sufficient fiber.

Key differences between prebiotics and probiotics

They both support your gut function. So what’s the difference between prebiotics and probiotics?

	Probiotics	Prebiotics
What Are They	Live beneficial microorganisms	Non-digestible fibers that feed those microbes
Function	Add beneficial microbes to the gut	Nourish and support existing microbes
Mechanism	Colonize (temporarily) and interact with the gut microbiome	Are fermented by gut bacteria into beneficial compounds (e.g., short-chain fatty acids)
Sources	Yogurt, kefir, fermented foods, and supplements	Fiber-rich foods like garlic, onions, bananas, asparagus, and whole grains
Stability	Sensitive to heat, storage, and stomach acid	More stable; not destroyed by digestion before reaching the gut

Benefits of prebiotics vs. probiotics

Given the differences in their nature and function, prebiotics and probiotics provide different benefits.

Probiotics	Prebiotics
Probiotics support the integrity of the intestinal lining—the gut barrier—which is an important part of digestive health.1 They support immune signaling by interacting with immune cells in the gut to help support immune responses. Probiotics interact with immune cells in the gut to help support immune responses. Probiotics compete with harmful microbes. Probiotics help support a balanced gut environment by contributing to your beneficial bacterial population. Probiotics support immune health. Research shows that a healthy gut microbiome contributes to balanced immune responses.² Find more on the Benefits of Probiotics here.	Prebiotics stimulate the growth and activity of beneficial gut bacteria. By selectively nourishing certain microbes, prebiotics help your gut maintain a balanced and healthy microbiota. This also aids in healthy, effective digestion. They survive the journey to the large intestine. Because they are not digested until they reach the colon, prebiotics aren’t used up before reaching their target. That makes them excellent fuel for beneficial gut bacteria in your large intestine (colon). The fermentation process helps improve stool quality and frequency. As prebiotics are fermented in the colon, they help improve your bowel movements. The fermentation process is linked with softer stools and increased stool frequency.³ If you have digestive discomfort, certain prebiotics may help mitigate it Prebiotics nourish beneficial bacteria that produce short-chain fatty acids. These compounds support gut barrier function and immune balance.

Probiotics

Prebiotics

Probiotics support the integrity of the intestinal lining—the gut barrier—which is an important part of digestive health.1

They support immune signaling by interacting with immune cells in the gut to help support immune responses. Probiotics interact with immune cells in the gut to help support immune responses.

Probiotics compete with harmful microbes. Probiotics help support a balanced gut environment by contributing to your beneficial bacterial population.

Probiotics support immune health. Research shows that a healthy gut microbiome contributes to balanced immune responses.²

Find more on the Benefits of Probiotics here.

Prebiotics stimulate the growth and activity of beneficial gut bacteria.
By selectively nourishing certain microbes, prebiotics help your gut maintain a balanced and healthy microbiota. This also aids in healthy, effective digestion.

They survive the journey to the large intestine.
Because they are not digested until they reach the colon, prebiotics aren’t used up before reaching their target. That makes them excellent fuel for beneficial gut bacteria in your large intestine (colon).

The fermentation process helps improve stool quality and frequency.
As prebiotics are fermented in the colon, they help improve your bowel movements. The fermentation process is linked with softer stools and increased stool frequency.³

If you have digestive discomfort, certain prebiotics may help mitigate it
Prebiotics nourish beneficial bacteria that produce short-chain fatty acids. These compounds support gut barrier function and immune balance.

Supporting gut health with daily routines

Is it better to take a prebiotic or a probiotic?
It’s not so much pre- vs probiotics, but how to incorporate both for better gut support. Let’s look at how various food sources or supplements could fit into your routine and support daily digestive comfort.

How to integrate more prebiotics into your diet

Regularly consume foods rich in non-digestible fiber. As with most things, consistency is the key here. Aim to consume prebiotic-rich fruits and vegetables every day. Your gut microbiota needs a constant supply of prebiotics. Here are food ideas to get more prebiotics naturally:

Fruits and vegetables: Bananas, apples, berries, watermelon, and grapefruit are all great sources of prebiotics. Vegetables with high levels of prebiotics include garlic, leeks, onions, asparagus, avocado, broccoli, spinach, and sweet potatoes.
Legumes: Beans, lentils, chickpeas, dried soy products, and peas are all great legume sources of prebiotics.
Grains: These include oats, barley, rye, and quinoa, all rich in one of the most commonly studied prebiotics, fructooligosaccharides.⁴
Seeds: Look for flaxseed, chia seeds, sunflower seeds, and pumpkin seeds for the highest concentration of prebiotics. You can also go exotic and incorporate seeds from fruits like date palm, jackfruit, mango, and durian.
Nuts: Nuts are a rich source of dietary fibers, polyphenols, and polysaccharides, all of which are prebiotic compounds that contribute to your gut health. If you want to choose just one, head for the almonds!⁵

Add a supplement to your morning routine. AG1 provides an easy (and delicious) way to consume prebiotics regularly. It also delivers comprehensive daily nutrition ingredients to help the prebiotics do their work and support your overall health.*

AG1 Next Gen’s research-backed formula includes a prebiotic complex (with ingredients like apple powder and inulin), intended to work alongside our selected probiotic strains to promote the growth of healthy bacteria.

Eat a balanced diet. Diverse plant-based foods and supplements have been shown to support gut microbiota regulation and overall associated health benefits. Variety is the spice of life, and the key to keeping your gut healthy.⁶

How to integrate more probiotics into your diet

Fermented foods with live cultures contain the most natural probiotics. These include yogurt, kefir, sauerkraut, kimchi, miso, tempeh, and kombucha. Eating these foods consistently will help introduce beneficial microbes to your gut and support your microbial diversity.

In addition to these probiotic-rich foods, or if you are unable to (or prefer not to) consume these foods, consider probiotic supplements to support your gut balance.

An easy way to get both

AG1 Next Gen’s research-backed formula offers both prebiotic and probiotic support for your gut.

It contains 37mg (10 Billion Viable Cells)† of the probiotic strains Lactobacillus rhamnosus GG, Lactobacillus acidophilus NCFM, Bifidobacterium lactis HN019, Lactobacillus casei LC-11, and Lactobacillus plantarum LP-115.
It includes a prebiotic complex with ingredients like apple and inulin, intended to work alongside the probiotic strains to promote more growth of healthy bacteria.

Pre- and probiotics work together in support of your optimal health. For the best results in your digestive (and overall) health journey, your gut needs both.

References:

Zheng Y, Zhang Z, Tang P, et al. Probiotics fortify intestinal barrier function: a systematic review and meta-analysis of randomized trials. Front Immunol. 2023;14:1143548. Published 2023 Apr 24. doi:10.3389/fimmu.2023.1143548
Zhou P, Chen C, Patil S, Dong S. Unveiling the therapeutic symphony of probiotics, prebiotics, and postbiotics in gut-immune harmony. Front Nutr. 2024;11:1355542. doi:10.3389/fnut.2024.1355542
De Fraia L, Christodoulides S, Patrikios I. Laxative effect of prebiotics in chronic constipation: Mechanisms of action. Magna Sci Adv Biol Pharm. 2023;9(2):8-13. doi:10.30574/msabp.2023.9.2.0046
Natale A, Fiori F, Turati F, La Vecchia C, Parpinel M, Rossi M. Quantification of Naturally Occurring Prebiotics in Selected Foods. Nutrients. 2025;17(4):683. https://doi.org/10.3390/nu17040683
Tahiri M, Gilbert JA. Examining the potential prebiotic effect of almonds. J Appl Microbiol. 2025;136(4):lxaf078. doi:10.1093/jambio/lxaf078
Bedu-Ferrari C, Biscarrat P, Langella P, Cherbuy C. Prebiotics and the Human Gut Microbiota: From Breakdown Mechanisms to the Impact on Metabolic Health. Nutrients. 2022;14(10):2096. https://doi.org/10.3390/nu14102096