One of the most studied probiotics in the world

BioGaia’s probiotic products with Limosilactobacillus reuteri (formerly known as Lactobacillus reuteri ) are among the most scientifically well-documented probiotics in the world. To date, the efficacy and safety of BioGaia’s different strains of L. reuteri have been documented in 258 clinical studies on approximately 21,000 people of all ages (Dec 2022).

127 studies of BioGaia’s strain of L reuteri have been conducted in children, ranging from newborns to 18 years old, and 131 studies in adults.

Our probiotic strains with L. reuteri


 L. reuteri Protectis (L. reuteri DSM 17938)

  • For gut comfort
  • 177 completed clinical trials on 17,000 individuals


 L. reuteri Prodentis (L. reuteri DSM 17938 and L. reuteri ATCC PTA 5289)

  • For gums and teeth
  • 64 completed clinical trials on 2,900 individuals


L. reuteri Gastrus (L. reuteri DSM 17938 and L. reuteri ATCC PTA 6475)

  • For GI tract
  • 8 clinical trials


L. reuteri Osfortis (L. reuteri ATCC PTA 6475)

  • For bone health
  • 1 clinical trial


L. reuteri Colus (L. reuteri ATCC PTA 4659)

  • Still under development for colon health
  • 1 clinical trial



Why choose L. reuteri?

  • L. reuteri is one of the few bacteria that have co-evolved with humans.
  • Our L. reuteri products are manufactured under controlled conditions and are of the highest quality.
  • The effectiveness and safety of these products are tested and documented in target populations, including newborns and elderly.
  • Our probiotics contain viable freeze-dried L. reuteri.
  • Live bacteria are guaranteed until expiration.
  • Probiotic bacteria are always defined at the strain level.


L. reuteri survive through the whole GI tract

The stomach’s acidic environment causes many probiotics to die. L. reuteri, however, survives throughout the entire GI tract. Samples taken from various parts of the body show that L. reuteri is present in:

  • Breast milk
  • The vagina
  • The mouth
  • The stomach
  • The small intestine
  • The large intestine
  • Faeces


Where do BioGaia’s probiotic strains come from?

The first strain of L. reuteri for human use, L. reuteri DSM 17938, was isolated in 1990 from the breast milk of a Peruvian mother living in the Andes. L. reuteri ATCC PTA 5289 was isolated from the oral cavity of a Japanese woman with exceptional good oral health. L. reuteri ATCC PTA 6475 is an anti-inflammatory strain isolated from breast milk of a Finnish woman.

Today, L. reuteri bacteria are produced under controlled conditions in modern production facilities. For bacteria to grow and duplicate, the right food and temperature are provided. Tests and quality control ensure that each dose contains the right number of viable organisms.


The right dose for colonisation

In order to achieve proper colonisation and have a beneficial effect, even indigenous bacteria such as BioGaia’s L. reuteri Protectis should be taken regularly.

L. reuteri temporarily binds to the epithelium that covers the GI tract and functions like an interior skin. This “inner skin” distinguishes between what our bodies should absorb and what they should not.

Since our epithelium replaces itself every four days, most of the L. reuteri cells are washed away within a week or two. Since L. reuteri colonisation is transient, maintaining adequate and stable levels of the bacteria in the GI tract requires daily intake.

Read more about Gatekeepers in the gut

A dose of 100 million units per day of L. reuteri Protectis is considered safe and efficient for children and adults. For other BioGaia products, the dose may vary. The dose is decided based on results from clinical trials.


Safe for all ages

Our products have been proven safe for babies, infants, children, healthy adults and immunocompromised adults. Even when our products have been taken at a dose of 10 billion units per day or 1,000 times the recommended daily dose, there have been no serious side effects observed.

L. reuteri throughout life

L. reuteri is a species of bacteria that is grounded in evolution. The bacteria live in the gastrointestinal tracts of animals, with each species carrying its own strains that are passed from generation to generation. Over millions of years, we humans and our ancestors have co-evolved with our own strains of L. reuteri.

As a result of this evolutionary process, L. reuteri contributes to human health. When humans are born, they are almost sterile, but first encounter L. reuteri during the birth process and while breastfeeding. As a key member of the gut microbiota, L. reuteri plays an important role in helping babies digest breast milk and solid food.

Throughout life, bacteria tighten the lining of the gut to prevent leakage and improve immune response. Furthermore, they release molecules that promote healthy and diverse microbiota and prevent the growth of pathogens. The gut microbiota needs to be supported, especially as we age, since the diversity of bacteria decreases when we get older.

Today, while some people still have L. reuteri in their microbiota, most people lack these strains due to our modern lifestyle. The depletion of L. reuteri from our gastrointestinal tract has been attributed to low-fibre diet, increased sanitation and antibiotic use. Cesarean deliveries have also contributed to this decline.

L. reuteri can be reintroduced through probiotics, but they must be replenished frequently, since the bacteria are constantly washed out of the GI tract.

What are probiotics?

The history of BioGaia