About
Lactobacillus acidophilus is a gram-positive, lactic acid-producing bacterium naturally found in the human gastrointestinal tract and commonly used as a probiotic starter culture in fermented dairy products such as yogurt, buttermilk, sour cream, and acidophilus milk. It is added to food to support gut microbiota balance and confer potential health benefits, and is widely used as both a functional food ingredient and probiotic supplement.
Safety summary
L. acidophilus has a long history of safe use in food, is GRAS-recognized by the FDA, and holds Qualified Presumption of Safety (QPS) status under the EFSA framework; no acceptable daily intake (ADI) is established, as it is a live microorganism rather than a chemical additive. Rare adverse events—principally bacteremia or sepsis—have been documented almost exclusively in severely immunocompromised individuals. Antibiotic resistance gene transfer from probiotic strains to commensal gut bacteria is a recognized safety consideration under both FDA and EFSA evaluation frameworks, requiring absence of acquired resistance as a condition of approval.
Regulatory landscape
| Jurisdiction | Status | Note |
|---|---|---|
| EFSA (European Food Safety Authority) (European Union) | Approved | L. acidophilus is assessed under EFSA's Qualified Presumption of Safety (QPS) framework for microorganisms intentionally introduced into the food or feed chain. QPS has been in operation since 2007. Safety qualification requires the absence of acquired transferable antibiotic resistance. L. acidophilus has also been assessed as a component in multiple EFSA FEEDAP panel opinions on probiotic feed additives (e.g., EFSA Journal 2022;20(9):7423). QPS does not cover allergenicity or hazards linked to formulation, which are assessed separately.source |
| FSSAI (Food Safety and Standards Authority of India) (India) | Approved | L. acidophilus is listed as a permitted starter culture organism in fermented milk and dairy products under FSSAI Food Product Standards Chapter 2.1 (Dairy Products and Analogues). For probiotic label claims in dairy products, ICMR (Indian Council of Medical Research) Guidelines for Evaluation of Probiotics in Food must be followed. Probiotic food products are also regulated under FSS (Health Supplements, Nutraceuticals, Foods for Special Dietary Uses, Foods for Special Medical Purpose, and Prebiotic and Probiotic Food) Regulations, 2022. Acidophilus milk is a listed standardized product under FSSAI.source |
| FDA (Food and Drug Administration) (United States) | Approved | Prior sanction granted for use as an optional ingredient in cultured milk, buttermilk, sour cream, cottage cheese, and yogurt (21 CFR Parts 131 and 133). Multiple strain-specific GRAS notices with no objection from FDA: GRN 000871 (L. acidophilus strain 30333, general conventional foods at 10^9–10^11 CFU/serving, excluding infant formula and USDA-regulated foods) and GRN 000865 (L. acidophilus ATCC SD5221, non-exempt milk/soy-based infant formula for term infants and formula for children ≥12 months). GRAS status predicated on use of nonpathogenic and nontoxicogenic strains under current good manufacturing practice (21 CFR 184.1(b)). |
Who should approach with care
Research citations
- 1PubMed. Safety assessment of probiotics for human use. pmc.ncbi.nlm.nih.gov
- 2FSSAI. FSSAI Food Product Standards – Chapter 2.1: Dairy Products and Analogues (Version 1, 01.09.2023), 2023. fssai.gov.in
- 3EFSA. Safety and efficacy of a feed additive consisting of Enterococcus faecium NBIMCC 8270, Lactobacillus acidophilus NBIMCC 8242, and other LAB (Probiotic Lactina®) for cats and dogs, 2022. efsa.europa.eu
- 4FDA. GRAS Notice No. GRN 000865 – Lactobacillus acidophilus NCFM (ATCC SD5221), 2020. fda.gov
- 5PubMed. Safety Aspects of Genetically Modified Lactic Acid Bacteria, 2020. pmc.ncbi.nlm.nih.gov
- 6FDA. GRAS Notice No. GRN 000871 – Lactobacillus acidophilus DDS-1 (strain 30333), 2020. fda.gov