L. reuteri Yoghurt: The Science Behind One of the World's Most Researched Probiotics

At Exercise Therapy Systems, we believe customers should never have to rely on marketing claims alone. We encourage everyone to ask questions, read the research and make informed decisions.

One question we are often asked is:

"Does L. reuteri yoghurt really work, and is there any scientific evidence behind it?"

The short answer is yes—there is a growing body of scientific research supporting specific strains of Limosilactobacillus reuteri. However, it's important to understand that not all L. reuteri strains are the same.

Why Strains Matter

Many probiotic products simply list "L. reuteri" on the label.

That tells you very little.

The scientific evidence is strain specific, meaning the benefits observed in research apply only to the exact strains that were studied.

Our starter culture contains the two most extensively researched strains:

• Limosilactobacillus reuteri DSM 17938
• Limosilactobacillus reuteri ATCC PTA 6475

These strains have been investigated in human clinical trials for digestive health, immune function, inflammation, gut barrier integrity and many other health applications.

What Makes L. reuteri Different?

Unlike many probiotics, L. reuteri naturally produces a substance called reuterin.

Reuterin is a naturally occurring antimicrobial compound that has been shown in laboratory studies to inhibit the growth of numerous undesirable bacteria while generally having much less effect on beneficial bacteria.

Researchers believe this is one of the reasons L. reuteri may help support a healthier gut microbiome.

Research Review:
https://www.frontiersin.org/journals/gastroenterology/articles/10.3389/fgstr.2023.1296048/full

What Does the Research Say?

The two strains used in our starter culture have been studied for:

• IBS (Irritable Bowel Syndrome)
• Constipation
• Gut inflammation
• Gut barrier integrity
• Immune regulation
• Oral health
• H. pylori support
• Infant gut health
• Skin health
• Bone health
• Gut microbiome balance

The strongest evidence currently exists for IBS and gastrointestinal health, with additional promising research in several other areas.

Human Clinical Trials

One of the largest recent randomized controlled trials investigated the combination of:

• DSM 17938
• ATCC PTA 6475

in 140 adults with moderate to severe IBS.

Researchers reported significant improvements in:

• IBS symptoms
• Stool consistency
• Quality of life
• Reduced intestinal inflammation (measured by faecal calprotectin)

Importantly, the probiotic demonstrated an excellent safety profile comparable with placebo.

PubMed:
https://pubmed.ncbi.nlm.nih.gov/41821785/

Gut Barrier & Inflammation

Another human study investigated these same strains for their effects on:

• intestinal permeability
• gut barrier function
• immune signalling
• inflammation

The study found improvements in gastrointestinal symptoms together with evidence of immune modulation and anti-inflammatory activity.

PubMed:
https://pubmed.ncbi.nlm.nih.gov/39485760/

L. reuteri and SIBO / CIBO

One of the most common questions we receive is whether L. reuteri yoghurt can help with SIBO (Small Intestinal Bacterial Overgrowth) or CIBO/IMO (intestinal methanogen overgrowth).

Current scientific evidence is promising but still emerging.

Researchers are interested in these strains because they have been shown to:

• produce reuterin
• support a healthier microbial balance
• reduce inflammation
• support gut barrier function
• potentially improve gut motility

Some clinical studies have also reported improvements in symptoms associated with methane-dominant overgrowth, including constipation and bloating, together with reductions in methane levels on breath testing after treatment with L. reuteri DSM 17938 in certain patients.

There is also an active registered clinical trial investigating these exact strains for preventing or reducing SIBO in people at increased risk.

Clinical Trial:
https://clinicaltrials.gov/study/NCT05484128

While these findings are encouraging, more high-quality human studies are needed before L. reuteri can be described as a proven treatment for SIBO/CIBO.

Why Make Yoghurt?

Our product is a starter culture, not simply a probiotic capsule.

When fermented correctly, the bacteria multiply substantially during the yoghurt-making process, resulting in many billions of live bacteria per serving while maintaining the same probiotic strains.

This approach has become increasingly popular following the work of Dr. William Davis, author of Super Gut, who discusses fermenting yoghurt using DSM 17938 and ATCC PTA 6475.

Educational Videos

If you would like to learn more, the following resources provide useful discussions on the science behind L. reuteri.

Dr. Eric Berg – Fix Your Gut with ONE Microbe

https://www.youtube.com/watch?v=nZV1oYv5Ddo

Dr. Eric Berg – More Affectionate, More Muscle, More Sleep

https://www.youtube.com/watch?v=I1T82XTscpc

Whole Shenanigans – SIBO & L. reuteri Yoghurt

https://www.youtube.com/watch?v=CCAHU-RRBac

How to Make L. reuteri Yoghurt (Dr. Davis Method)

https://www.youtube.com/watch?v=_d319BPTKpY

Dr Berg Facebook Reel

https://www.facebook.com/share/r/17g1jZnAtT/

Scientific References

Cruchet et al. Randomized controlled trial using DSM 17938 and ATCC PTA 6475 in adults with IBS.
https://pubmed.ncbi.nlm.nih.gov/41821785/

König et al. Gut barrier integrity, inflammation and immune modulation.
https://pubmed.ncbi.nlm.nih.gov/39485760/

Frontiers in Gastroenterology Review
Mechanisms of L. reuteri, reuterin production, immune modulation and gastrointestinal health.
https://www.frontiersin.org/journals/gastroenterology/articles/10.3389/fgstr.2023.1296048/full

ClinicalTrials.gov
Registered clinical trial investigating DSM 17938 and ATCC PTA 6475 for SIBO prevention.
https://clinicaltrials.gov/study/NCT05484128

Our Commitment

At Exercise Therapy Systems, we are committed to providing products supported by scientific evidence and being transparent about what the research does—and does not—show.

We encourage customers to review the published literature, ask questions and make informed decisions. If you would like further information about the strains used in our starter culture or copies of published research, please don't hesitate to contact us.

Knowledge continues to evolve as new studies are published, and we look forward to seeing what future research reveals about these fascinating probiotic strains.