Lacticaseibacillus rhamnosus

About

What it is and where it shows up.

Lacticaseibacillus rhamnosus (formerly Lactobacillus rhamnosus) is a Gram-positive, non-motile, non-spore-forming, rod-shaped lactic acid bacterium originally isolated from the human gut, widely used as a probiotic in fermented dairy products, functional foods, and dietary supplements. It is added to food to support gut health and has a long history of safe use in fermented dairy products and infant formulas across multiple markets.

Safety summary

The regulatory and scientific consensus.

L. rhamnosus is broadly recognised as safe for healthy adults; multiple FDA GRAS notices and EFSA's Qualified Presumption of Safety (QPS) listing confirm this consensus. Adverse events are rare and have occurred almost exclusively in individuals with an underlying disease or compromised immune system. No virulence factors, toxigenicity genes, or clinically concerning antibiotic-resistance determinants have been identified in well-characterised strains, though intrinsic vancomycin resistance is common to the species and should be monitored.

Regulatory landscape

What food-safety regulators have decided.

Jurisdiction	Status	Note
Health Canada (Canada)	Approved	L. rhamnosus is accepted for use in food products in Canada; specific probiotic health claims are subject to separate regulatory review by Health Canada.source
EFSA (European Food Safety Authority) (European Union)	Approved	L. rhamnosus holds Qualified Presumption of Safety (QPS) status from EFSA for use in food and as a feed additive; EFSA recommends continued surveillance of the species. Antibiotic susceptibility to ampicillin, erythromycin, gentamicin, streptomycin, and tetracycline must be confirmed at strain level; intrinsic vancomycin resistance is considered non-transferable.source
FSSAI (Food Safety and Standards Authority of India) (India)	Approved	Lactobacillus spp. including L. rhamnosus are permitted as probiotics under the FSS (Health Supplements, Nutraceuticals, Food for Special Dietary Use, Food for Special Medical Purpose, Functional Food and Novel Food) Regulations, 2016. Probiotic properties must be substantiated; labelling must include genus, species, strain designation, viable count at end of shelf life, and recommended serving size. ICMR-DBT guidelines provide additional guidance.source
FDA (Food and Drug Administration) (United States)	Approved	Multiple strains (e.g., MP108, DSM 33156, ATCC PTA-126815, CBT LR5, CGMCC 21225) have received GRAS no-objection letters from FDA for use in beverages, cereals, dairy, grain products, confections, and foods for infants (excluding infant formula) at up to 1×10⁹ CFU/serving.

Who should approach with care

Whose guidance would steer them away.

Other — Immunocompromised individuals (e.g., those with HIV/AIDS, undergoing chemotherapy, or critically ill) face a rare but documented risk of bacteremia and sepsis; adverse events reported in surveillance studies occurred almost exclusively in subjects with underlying disease or health conditions.

Infants — While some L. rhamnosus strains have been reviewed for infant foods (excluding infant formula) in the US and are used in European infant products, use in premature or very low birth weight infants should be medically supervised given rare reported cases of probiotic-related sepsis in neonates.

Ibd — Patients with compromised gut barrier integrity (e.g., severe IBD with active mucosal disease) should consult a physician before use, as translocation of probiotic bacteria across a damaged epithelium, though rare, has been reported.

Research citations

The sources behind this verdict.

1FDA. GRAS Notice (GRN) 1240 Agency Response Letter – Lactobacillus rhamnosus ATCC PTA-126815. fda.gov
2EFSA. Safety and efficacy of Lactobacillus rhamnosus CNCM I-3698 and Lactobacillus farciminis CNCM I-3699 as a feed additive for all animal species. ncbi.nlm.nih.gov
3PubMed. Tolerance and safety of the potentially probiotic strain Lactobacillus rhamnosus PRSF-L477: a randomised, double-blind placebo-controlled trial in healthy volunteers. pubmed.ncbi.nlm.nih.gov
4PubMed. Adherence capability and safety assessment of an indigenous probiotic strain Lactobacillus rhamnosus MTCC-5897. pubmed.ncbi.nlm.nih.gov
5FDA. GRAS Notice 1084 – Lactobacillus rhamnosus CBT LR5, 2023. fda.gov
6FSSAI. FSS (Health Supplements, Nutraceuticals, FSDU, FSMP, Functional Food and Novel Food) Regulations Compendium, 2021, 2021. fssai.gov.in

Independently researched6 citations