What is a good source of Lactobacillus reuteri?

Due to modern diets and increased sanitation, many people now lack the beneficial probiotic Lactobacillus reuteri, a key microbe that co-evolved with humans. Fortunately, you can reintroduce this important bacterium into your system through specific dietary and supplemental sources.

Quick Summary

Both fermented foods and dietary supplements offer sources for the probiotic L. reuteri, each with distinct advantages and drawbacks for gut health. Supplements provide consistent doses of scientifically studied strains, while food sources, though beneficial, can have variable and often unpredictable amounts.

Key Points

• Supplements offer consistency: For a reliable, high-dose source of specific L. reuteri strains, supplements are the most effective option.

• Fermented foods are variable: While some fermented foods can contain L. reuteri, the presence and quantity are often unpredictable.

• Look for specific strains: When buying supplements, check for clinically studied strains like DSM 17938 or ATCC 6475.

• Support with prebiotics: Nourish your gut's beneficial bacteria by including fiber-rich foods like garlic, onions, and bananas in your diet.

• Consider homemade yogurt: Making your own yogurt with a specialized L. reuteri starter culture can produce a highly concentrated dietary source.

• Strain matters for specific effects: Different strains of L. reuteri have been studied for different purposes, such as digestive health (DSM 17938) or immune modulation (ATCC 6475).

Understanding the Best Sources of Lactobacillus reuteri

Lactobacillus reuteri (recently reclassified as Limosilactobacillus reuteri) is a beneficial probiotic bacterium with a range of health benefits, including supporting gut, oral, and systemic health. However, unlike more common probiotics, it is not consistently found in all probiotic foods. To get a reliable and effective dose, you must know where to look. The two primary avenues are fermented foods and dietary supplements, each offering different levels of consistency and strain specificity.

Fermented Foods: A Natural but Variable Source

Fermented foods can be a natural and delicious way to increase your probiotic intake, and some may contain L. reuteri. However, the presence and quantity of this specific strain can be unpredictable and depend heavily on the starter culture and fermentation process.

Fermented dairy products

• Specialized Yogurt and Kefir: While most commercial yogurts and kefirs contain different strains, some brands produce special versions using specific L. reuteri starter cultures to ensure higher concentrations. You can also make your own yogurt at home using a starter that contains an L. reuteri strain like DSM 17938.
• Certain Cheeses: Varieties like aged cheddar, Parmigiano Reggiano, or Gouda can sometimes harbor L. reuteri strains, especially those made with specific non-starter lactic acid bacteria cultures.

Fermented vegetables and grains

• Sauerkraut and Kimchi: These lactic acid-fermented vegetable dishes, popular in Eastern Europe and Korea, can be a source of various probiotics, including L. reuteri, if unpasteurized and fermented naturally.
• Sourdough Bread: The traditional, long-fermentation process of certain sourdoughs can involve L. reuteri.
• Fermented Tofu: In some regions, fermented tofu may also contain this beneficial bacterium.

Probiotic Supplements: The Reliable Option

For targeted health benefits and consistent, high-potency dosing, dietary supplements are often the most effective source. Manufacturers use specific, well-researched strains to ensure a reliable outcome, something difficult to guarantee with most fermented foods.

Key L. reuteri strains in supplements

• DSM 17938 (BioGaia Protectis): This is one of the most clinically studied strains, known for its effectiveness in treating infant colic and improving gastrointestinal health.
• ATCC PTA 5289 (BioGaia Prodentis): Often combined with DSM 17938 in oral health products, this strain supports dental health and gum health.
• ATCC 6475: This strain is studied for its ability to increase oxytocin and testosterone levels and improve bone health, particularly in animal studies.

Foods that Support the Growth of L. reuteri

Besides consuming L. reuteri directly, you can also support the natural growth of this bacterium in your gut by eating prebiotic foods. These foods contain specific fibers that nourish beneficial gut bacteria.

Examples of prebiotic foods:

• Garlic and onions
• Bananas
• Whole grains
• Artichokes
• Beans and legumes
• Asparagus

Comparison Table: Fermented Foods vs. Probiotic Supplements

Feature	Fermented Foods	Probiotic Supplements
Strain Specificity	Often unknown; depends on starter culture and process.	Contains targeted, specific, and clinically documented strains.
Consistency & Dosage	Highly variable and unreliable. Not guaranteed to contain L. reuteri.	Provides a precise and consistent dose (CFU count) per serving.
Gut Colonization	Provides diverse bacteria that may support overall gut flora.	Specific strains are often chosen for their known ability to colonize the gut.
Cost	Can be a cost-effective dietary choice if made at home.	Typically more expensive per serving but offers reliability.
Suitability	Best for general gut health and dietary diversity.	Ideal for targeting specific health concerns where a known dose is required.

Maximize Your L. reuteri Intake

To ensure you are getting the most from your L. reuteri sources, consider these tips:

1. Read Labels Carefully: For both foods and supplements, check the label for the specific strain (e.g., DSM 17938) and the CFU count to ensure efficacy. Avoid products that do not specify the strain.
2. Choose Unpasteurized: When opting for fermented foods like sauerkraut or pickles, always select unpasteurized versions, as pasteurization kills the beneficial bacteria.
3. Combine with Prebiotics: Pair your L. reuteri intake with fiber-rich prebiotic foods like bananas, onions, or asparagus to provide nourishment for the bacteria and help them thrive.
4. Homemade is Best for Food: For fermented products, making them at home with a reliable starter culture is the most effective way to control the presence and concentration of L. reuteri.
5. Time Your Supplements: If you are taking antibiotics, space out your probiotic supplement by at least two hours to prevent the antibiotic from killing the beneficial bacteria.

Conclusion

Finding a good source of Lactobacillus reuteri is a blend of exploring fermented foods and utilizing targeted supplements. While fermented foods offer broad-spectrum probiotic support and are excellent for general gut diversity, they provide an inconsistent and often unpredictable amount of L. reuteri. In contrast, high-quality supplements offer a reliable, concentrated, and strain-specific dose, making them the superior choice for addressing specific health goals. For comprehensive gut health, a combination of a diet rich in prebiotic fiber and targeted supplementation is the most effective strategy.

For further scientific detail on L. reuteri and its role in human health, consult the National Institutes of Health: PMC5917019.

Frequently Asked Questions

What foods are the best sources of *Lactobacillus reuteri*?

Fermented foods that may contain L. reuteri include specialized yogurts, certain aged cheeses, kefir, sauerkraut, kimchi, and sourdough bread. However, supplements are a more reliable source for specific strains and consistent dosages.

Is it better to get *L. reuteri* from food or supplements?

Supplements are often a more reliable and concentrated source, providing specific, clinically-studied strains and consistent dosages. Fermented foods are great for general gut health but contain variable and often unknown amounts of L. reuteri.

Which strains of *L. reuteri* should I look for in supplements?

Look for specific, well-documented strains like DSM 17938, often found in BioGaia Protectis products, or ATCC 6475, which are linked to various health benefits.

How can I maximize my body's natural *L. reuteri* levels?

Besides consuming sources directly, you can support the growth of native L. reuteri by eating a balanced diet rich in prebiotic fiber from foods like garlic, onions, bananas, and whole grains.

What is the difference between homemade and commercial yogurt for *L. reuteri*?

Commercial yogurts may not contain L. reuteri or have inconsistent amounts, as their primary cultures differ. Homemade yogurt, made with a specific L. reuteri starter culture, can be fermented for a longer time to achieve higher and more reliable bacterial counts.

Does *L. reuteri* help with digestive issues?

Yes, specific strains of L. reuteri, particularly DSM 17938, have been clinically shown to help with conditions like infant colic, constipation, and stomach pain.

Are there other natural sources of *L. reuteri*?

L. reuteri is found naturally in breast milk, and studies have shown its presence in some plant-based foods like yams, beans, and artichokes, though these amounts can be unpredictable.