Limosilactobacillus reuteri, formerly Lactobacillus reuteri, is a probiotic bacterium naturally found in the human gastrointestinal tract, urinary tract, and breast milk. Its classification was updated in 2020 to better reflect its scientific characteristics. As a lactic acid bacterium, it is a component of the body’s complex microbial communities.
Key Health Benefits
Limosilactobacillus reuteri is recognized for its contributions to digestive wellness by helping maintain a balanced gut microbiome. It produces antimicrobial compounds, like reuterin, that inhibit the growth of potentially harmful microbes. This action helps prevent an overgrowth of these bacteria, supporting overall gut stability.
This probiotic has been studied for its effects on common gastrointestinal issues. It may help reduce constipation, shorten the duration of diarrhea in children, and manage symptoms of irritable bowel syndrome (IBS). When used with standard treatments for Helicobacter pylori infections, L. reuteri can also reduce the side effects of those therapies.
The benefits of L. reuteri extend to infant care, particularly in managing colic, which is characterized by excessive crying. The probiotic appears to improve colic by reducing gut inflammation and helping establish a stable microbiome in the infant’s digestive system. This can soothe the digestive discomfort that contributes to colic.
L. reuteri also benefits oral health. An imbalance in the mouth’s microbiome can lead to gingivitis and periodontal disease. Specific strains of L. reuteri improve oral health by competing with and inhibiting the bacteria responsible for these conditions, supporting healthier gums and teeth.
This probiotic also influences the immune system. Certain L. reuteri strains can modulate immune responses by regulating inflammation. They have been observed to reduce pro-inflammatory cytokines while promoting regulatory T cells, which suppress excessive immune reactions. This dual action of strengthening the intestinal barrier and modulating immune activity may help ameliorate certain inflammatory conditions.
Natural and Supplemental Sources
While Limosilactobacillus reuteri is a natural human microbe, changes in diet and lifestyle have reduced its prevalence. Some fermented foods like certain yogurts or sauerkraut may contain L. reuteri, but its inclusion is inconsistent. Fermented meats and other dairy products are also potential but uncommon sources.
Due to its scarcity in food, dietary supplements are the most reliable way to obtain a consistent amount of L. reuteri. Supplements offer a concentrated and standardized quantity of specific strains and are available in several forms:
- Capsules
- Chewable tablets
- Powders
- Liquid drops
Not all fermented foods contain this probiotic. Standard kefir or most commercial yogurts do not have L. reuteri unless it is specifically added. Individuals seeking its benefits should look for products that explicitly list Limosilactobacillus reuteri on the label.
Dosage and Administration
The dosage of Limosilactobacillus reuteri is measured in colony-forming units (CFUs), which indicate the number of viable bacteria. Research has used doses from 100 million to over 50 billion CFUs daily, depending on the health target and the individual. Following the manufacturer’s instructions on the product label is a sound starting point.
The specific strain of L. reuteri determines its effectiveness. For example, the strain DSM 17938 is studied for reducing crying time in infants with colic. The ATCC PTA 6475 strain has been researched for its anti-inflammatory and immune-supporting properties. Some products combine these strains for complementary effects.
Consistency is important, as the bacteria are naturally expelled from the body. Supplements can be taken with or without food but should not be mixed with hot beverages, which can destroy the live bacteria. If taking antibiotics, space out the probiotic dose by at least two to three hours to ensure its viability.
Safety and Potential Side Effects
Limosilactobacillus reuteri is considered safe for most healthy individuals and has been used in studies for up to six months in adults. When first starting, some people may experience temporary gas, bloating, or changes in bowel habits. These initial side effects are usually short-lived and resolve as the gut microbiome adapts.
Certain populations should exercise caution with L. reuteri supplements. Individuals with severely weakened immune systems, such as those undergoing chemotherapy or with HIV/AIDS, should consult a healthcare provider first. There have been rare reports of probiotics causing infections in these vulnerable groups.
People with damaged heart valves or who are critically ill should also seek medical advice before use. While uncommon, there is a risk of infection in these specific medical situations. For the general population, L. reuteri is well-tolerated and considered a safe way to support various aspects of health.