Where to get L. reuteri naturally?

November 17, 2025 •

4 min read

While modern lifestyles have depleted L. reuteri from the gut microbiota of many people, this beneficial probiotic can be found in several natural sources. A balanced approach that combines specific fermented foods with prebiotic-rich items can help reintroduce and nourish the L. reuteri in your system.

Quick Summary

This guide covers natural and reliable dietary sources of L. reuteri, including homemade fermented products and prebiotic foods. It outlines how to prepare specific yogurts and discusses the differences between food-based and supplemental bacteria for gut health.

Key Points

Homemade Fermentation is Key: While some commercial fermented foods might contain L. reuteri, creating your own yogurt with specific starter cultures is the most reliable way to achieve high bacterial counts.
Prebiotic Foods Boost Growth: Supplementing your diet with prebiotic-rich foods such as chicory root, garlic, onions, and artichokes provides fuel for beneficial bacteria like L. reuteri.
Natural Infant Source is Breast Milk: L. reuteri is naturally present in human breast milk, helping to establish an infant's early microbiome.
Not All Probiotics Are Equal: The effectiveness of a probiotic is strain-specific. Look for clinically proven strains like DSM 17938 and ATCC PTA 6475 for targeted health benefits.
Consistency Over Intensity: Regular intake through food or supplementation is necessary, as L. reuteri is naturally expelled from the body over time.
Avoid Antagonist Factors: Limiting processed foods, excessive alcohol, and unnecessary antibiotics can help maintain a healthy gut microbiome where L. reuteri can thrive.
High Potency DIY Yogurt: A 36-hour, low-temperature fermentation process is necessary to achieve the therapeutic levels of L. reuteri found in specialized yogurt recipes.

The Challenge of Finding L. reuteri in the Modern Diet

Limosilactobacillus reuteri (reclassified from Lactobacillus reuteri in 2020) is a lactic acid bacterium that is a natural inhabitant of the human gastrointestinal tract. Despite its historical presence, many people today have significantly reduced levels due to modern lifestyles, including diets low in fiber and fermented foods, high sanitation standards, and frequent antibiotic use. This makes it more difficult to obtain this specific probiotic naturally compared to our ancestors. However, intentional dietary choices can help re-establish a healthy population.

Fermented Foods: A Potential but Unpredictable Source

Fermented foods are often cited as a source of L. reuteri, but the actual quantity and viability of the bacteria can vary widely depending on the preparation and processing methods. While some traditionally fermented products may contain certain strains, the most reliable methods often involve cultivating the bacterium at home under specific conditions.

Yogurt and Kefir: Traditional yogurt and kefir production may or may not contain L. reuteri. To ensure a significant presence of beneficial L. reuteri strains, a specific method involving a starter culture and a longer fermentation period is required. This technique involves fermenting milk or half-and-half with a dedicated L. reuteri starter culture for 36 hours at a consistent, low temperature of around 100°F (38°C).
Sauerkraut and Kimchi: These fermented vegetables are produced through lactic acid fermentation and may contain L. reuteri. However, pasteurization processes can kill off the beneficial bacteria, so it is crucial to choose raw, unpasteurized versions to reap any potential probiotic benefits.
Other Fermented Goods: Some other fermented products like miso and sourdough bread have been mentioned as potential sources, though the presence of specific strains like L. reuteri is not guaranteed and can be unpredictable.

Breast Milk: Nature's Original Source

For infants, breast milk is a natural and primary source of L. reuteri. The presence of this probiotic helps seed the baby's developing microbiome right from the beginning of life. Studies have shown that L. reuteri strains isolated from breast milk, such as DSM 17938, play a significant role in promoting immune system development and gut health in infants.

Feeding the Good Bacteria: The Role of Prebiotics

Beyond consuming foods that contain L. reuteri, it is essential to eat items that promote the growth and maintenance of beneficial gut bacteria already present. These are known as prebiotics, which are non-digestible fibers that nourish probiotics.

Chicory Root: A potent source of inulin, a type of prebiotic fiber that feeds beneficial bacteria.
Garlic and Onions: These alliums contain fructans and other prebiotic fibers that can support a healthy gut microbiome.
Artichokes: Both Jerusalem and globe artichokes are excellent sources of inulin and other fibers.
Legumes: Beans, chickpeas, and lentils provide a rich source of resistant starch and fiber that nourish gut flora.
Bananas: Especially when slightly green, bananas contain resistant starch that acts as a prebiotic.

DIY L. reuteri Yogurt for High Bacterial Counts

To obtain reliably high concentrations of L. reuteri, culturing it at home is the most effective method. This process requires a specific L. reuteri starter culture (such as BioGaia Gastrus tablets), milk or half-and-half, and a prebiotic fiber like inulin. The long fermentation period (30-36 hours) at a low, consistent temperature (around 100°F) allows the bacteria to multiply exponentially, creating a potent, concentrated dose. This homemade yogurt is markedly different from conventional yogurt, which is fermented for a shorter time and contains different strains.

Natural Sources vs. Commercial Supplements

To better understand how to obtain L. reuteri, consider the following comparison between natural food sources and supplements.


Feature	Natural Food Sources (Traditional Fermentation)	Commercial Supplements (e.g., BioGaia) & DIY Yogurt
Bacterial Count	Unpredictable; can be low and variable depending on preparation.	High and consistent; supplements are standardized, while homemade yogurt produces trillions of bacteria.
Strain Specificity	Strain types are unknown and vary by source.	Strains are specified (e.g., DSM 17938, ATCC PTA 6475), with clinically researched benefits.
Reliability	Unreliable for achieving specific, high concentrations.	Highly reliable for consistent and therapeutic doses.
Additional Nutrients	Contains naturally occurring nutrients from the whole food source.	Often a more concentrated dose of the specific probiotic without extra nutrients.
Convenience	Requires sourcing raw, unpasteurized products; less convenient for specific health goals.	Supplements are very convenient; homemade yogurt requires more effort but yields higher counts.

Conclusion: A Multi-faceted Strategy

While finding reliably high concentrations of L. reuteri in store-bought fermented foods can be challenging due to modern processing techniques, several natural approaches can support your gut health. Homemade L. reuteri yogurt, using a specific starter culture and extended fermentation, offers a robust and concentrated source of this beneficial probiotic. Pairing this with a diet rich in prebiotic foods like garlic, artichokes, and legumes can further nourish and support a thriving gut microbiome. For those seeking convenience or specific clinical strains, high-quality supplements remain a reliable option, but focusing on a diverse, whole-food diet is the cornerstone of long-term gut health.

Promote Gut Health Naturally with a Varied Diet

By incorporating a variety of high-fiber fruits, vegetables, and whole grains into your meals, you create a diverse and nourishing environment in your gut. This ecosystem supports the growth of a wide range of beneficial bacteria, including L. reuteri, helping to crowd out less desirable microbes. Combining this diverse diet with targeted homemade L. reuteri yogurt can provide a powerful one-two punch for enhancing your microbiome naturally. For example, adding some homemade yogurt to a smoothie with a handful of oats or a mashed banana offers both prebiotics and a high dose of L. reuteri.

Visit Luvele's recipe blog for detailed instructions on making L. reuteri yogurt at home.

Frequently Asked Questions

Reliable food sources for L. reuteri are limited and unpredictable in terms of concentration. The most reliable food source is homemade yogurt specifically cultured with a high-potency L. reuteri starter and fermented for 36 hours.

While some commercial yogurts and kefirs may contain other probiotics, they typically do not contain the specific strains of L. reuteri (like DSM 17938 and ATCC PTA 6475) or concentrations found in homemade versions. The fermentation process for regular yogurt is too short and at the wrong temperature to produce the high counts needed for therapeutic effects.

Yes, supplements are a common and reliable way to obtain L. reuteri, especially if you need specific, clinically researched strains. However, for achieving the very high bacterial counts required for certain conditions, homemade fermented products like L. reuteri yogurt are often recommended.

Some traditionally fermented plant-based foods like sauerkraut and kimchi, if unpasteurized, may contain some lactic acid bacteria, including potentially L. reuteri. However, their content is not standardized. Prebiotic plant-based foods, such as artichokes, beans, and certain whole grains, help to nourish existing beneficial gut bacteria.

To make L. reuteri yogurt, you will need a specific starter culture (like BioGaia Gastrus tablets), a food source (like half-and-half or milk), and a prebiotic fiber (like inulin). The mixture is fermented for 36 hours at a low temperature of around 100°F (38°C) using a specialized yogurt maker.

The long, low-temperature fermentation (36 hours at 100°F) is necessary for the specific strains of L. reuteri to multiply to therapeutic levels, which are much higher than those in standard yogurts. This extended process creates a product with a profoundly higher probiotic concentration.

Prebiotics are non-digestible fibers that serve as food for probiotics, including L. reuteri, helping them thrive in the gut. By consuming prebiotic-rich foods like garlic, onions, and artichokes, you create a more hospitable environment for L. reuteri to grow and flourish.