Probiotic
Lactobacillus acidophilus
Also known as: Acidophilus, Bacillus acidophilus, L. acidophilus, Lactobacillus acidophilus
Foundational probiotic strain for vaginal and gut health. One of the most studied probiotic species.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Every Lactobacillus acidophilus product we have scored
| # | Product | Score | Per serving |
|---|---|---|---|
| 1 | Thorne FloraSport 20B® | 86 A- | $1.40 |
| 2 | Thorne Women's Daily Probiotic | 69 B | $1.30 |
| 3 | Bluebonnet Nutrition MILK FREE PROBIOTIC ACIDOPHILUS & FOS POWDER | 69 B | $0.39 |
| 4 | Bluebonnet Nutrition MILK-FREE PROBIOTIC ACIDOPHILUS & FOS | 66 B- | $0.39 |
| 5 | Bluebonnet Nutrition ADVANCED PROBIOTICS CHEWABLE ACIDOPHILUS | 64 B- | $0.43 |
Scored on dose accuracy, form, label transparency and third-party testing. Per-serving cost is list price divided by servings per container. No brand pays to be listed or ranked.
Common questions
How much Lactobacillus acidophilus should I take?
The typical range is 1-10 billion CFU daily. Safe long-term
When should I take Lactobacillus acidophilus?
Any time. Can take either way.
Which form of Lactobacillus acidophilus is best?
Capsules — Refrigerated often best. Other forms in the catalog: Powder, Foods.
Is Lactobacillus acidophilus safe?
Commonly reported: Gas initially. Serious warnings: Rare sepsis in immunocompromised. Safe
Which Lactobacillus acidophilus supplement scores highest?
Thorne FloraSport 20B®, at 86/100. Scored on dose accuracy, form, label transparency and third-party testing — no brand pays to be listed or ranked.
Primary uses
- Gut health
- Vaginal health
- Immune support
- Lactose digestion
What systematic reviews concluded
Outcomes that systematic reviews of Lactobacillus acidophilus reached a verdict on: 4 with a benefit, 3 unclear. Each is quoted from a review and linked to it on PubMed. How these were read.
Reviews found a benefit (4)
“The combination of Lactobacillus acidophilus and Lactiplantibacillus plantarum demonstrated the highest efficacy, achieving up to 80% reduction in total biogenic amine levels.” PMID 41494586
“Probiotics supplementation significantly reduced insulin resistance (MD: -1.05 HOMA-IR score, p < 0.00001)” PMID 40550754
“specific probiotic strains, including L. acidophilus, L. rhamnosus, L. fermentum, S. cerevisiae, and S. boulardii, may prevent TD.” PMID 38458507
“Lactobacillus acidophilus DDS-1 ranked first (surface under the cumulative ranking, SUCRA, 92.9%)” PMID 37686889
Not enough to say: mental health symptoms in ibs; lactose intolerance symptoms; exercise performance.
3 findings from reviews in specific patient groups (such as cancer, pregnancy or surgery) are not shown here.
How it works
- Produces lactic acid
- Inhibits pathogens
- Supports gut barrier
Dosage
- Typical range
- 1-10 billion CFU daily
- Timing
- Any time
- With food
- Can take either way
- Duration
- Safe long-term
- Special populations
- Women's health, antibiotic recovery
Forms
- Capsules
- Powder
- Foods
Safety
Common side effects
- Gas initially
Contraindications
- Severe immunocompromise
Products containing Lactobacillus acidophilus
Top-scoring supplements in our catalog that list Lactobacillus acidophilus on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Evidence notes
Well-studied probiotic strain
Grade A: Multiple well-designed human trials support the main claims.
Related in Probiotic
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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.