Limosilactobacillus reuteri is a lactic acid bacterium found in a variety of natural environments, including the gastrointestinal tract of humans and other animals.
At the turn of the 20th century, L. reuteri was recorded in scientific classifications of lactic acid bacteria,[1] though at this time it was mistakenly grouped as a member of Lactobacillus fermentum.
[2][5][6] It appears to be essentially ubiquitous in the animal kingdom, having been found in the gastrointestinal tracts and feces of healthy humans,[7] sheep, chickens,[8] pigs,[9] and rodents.
[17][18] In the late 1980s, Walter Dobrogosz, Ivan Casas and colleagues discovered that L. reuteri produced a novel broad-spectrum antibiotic substance via the organism's fermentation of glycerol.
[28][29] Some people, such as those with compromised immune systems, short bowel syndrome, central venous catheters, heart valve disease, and premature infants, may be at higher risk for adverse events.
[30] Rarely, consumption of probiotics may cause bacteremia, fungemia and sepsis, potentially fatal infections, in children with compromised immune systems or who are already critically ill.[31] One of the better documented effects of L. reuteri is a significant reduction of symptom duration in pediatric diarrheal disease.
Meta-analysis of randomized studies suggests that L. reuteri can reduce the incidence of sepsis and shorten the required duration of hospital treatment in this population.
[45] Growing evidence indicates L. reuteri is capable of fighting the gut pathogen Helicobacter pylori, which causes peptic ulcers and is endemic in parts of the developing world.
[46] Another study found the addition of L. reuteri to omeprazole therapy dramatically increased (from 0% to 60%) the cure rate of H. pylori-infected patients compared to the drug alone.
[47] Yet another study showed that L. reuteri effectively suppressed H. pylori infection and decreased the occurrence of dyspeptic symptoms, although it did not improve the outcome of antibiotic therapy.
[52] Limosilactobacillus reuteri may be capable of promoting dental health, as it has been proven to kill Streptococcus mutans, a bacterium responsible for tooth decay.
[54] Lactobacillus reuteri and other probiotics may influence the gut microbiome in ways that protect against bone loss, common in post-menopausal women.
[60] Similar results have been found in adults; those consuming L. reuteri daily end up falling ill 50% less often, as measured by their decrease use of sick leave.
Limosilactobacillus reuteri confers a high level of resistance to the pathogen Salmonella typhimurium, halving mortality rates in mice.
[64] The protozoic parasite Cryptosporidium parvum causes severe watery diarrhea, which can become life-threatening in immunocompromised (as in individuals infected with HIV) patients.
[13] Some protective effect against the yeast Candida albicans has been found in mice, but in this case, L. reuteri did not work as well as other probiotic organisms, such as L. acidophilus and L.
[66] In juvenile commercial livestock, such as turkey poults and piglets, body weight and growth rate are good health indicators.
Animals raised in the dirty, crowded environments of commercial farms are generally less healthy (and therefore weigh less) than their counterparts born and bred in cleaner spaces.
[68] A similar study on piglets showed L. reuteri is at least as effective as synthetic antibiotics in improving body weight under crowded conditions.
[13] Treating colonic tissue from rats with acetic acid causes an injury similar to the human condition ulcerative colitis.