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Head-to-head evidence comparison — which supplement is right for you?
L. acidophilus vs L. reuteri DSM 17938: L. reuteri DSM 17938 has the stronger overall evidence (6 vs 5/10); they're alternatives for improve digestion — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
L. reuteri DSM 17938 wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Too few graded studies
Top outcomes
Verdict
Mostly mechanism / observational
Top outcomes
Shared outcomes (1)
Outcomes where both L. acidophilus and L. reuteri DSM 17938 have evidence — compare verdict strength side-by-side.
1-100 billion CFU (10^9 to 10^11) per serving — the range FDA reviewed without objection for L. acidophilus DDS-1 in foods generally (GRAS Notice GRN 871); La-14 was noticed at 1 billion CFU per 250 g serving (GRN 502) (the one cited trial that states a dose used 10 billion CFU a day)
Any time of day
A product naming its strain (e.g. NCFM, DDS-1, La-14, La-5)
1 x 10^8 CFU daily (5 drops) for infant colic — the dose used in every positive trial
Any time of day
Oil-suspension drops standardized to DSM 17938
Weeks
Weeks
Course of antibiotics
1-3 weeks
n/a
1-3 days
4 weeks
Lactobacillus acidophilus DDS-1 and Bifidobacterium lactis UABla-12 Improve Abdominal Pain Severity and Symptomology in Irritable Bowel Syndrome: Randomized Controlled Trial.
Nutrients (2020) · Rct · n=330
Randomised, double-blind, placebo-controlled multicentre trial in 330 adults with IBS (Rome IV), allocated 1:1:1 to placebo, L. acidophilus DDS-1 alone or B. lactis UABla-12 alone, each at 1 × 10^10 CFU/day for six weeks
The effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance - a randomized, double-blind, placebo-controlled, crossover clinical trial.
Nutr J (2016) · Crossover
Randomised, double-blind, placebo-controlled crossover trial in adults with self-reported lactose intolerance confirmed by a lactose challenge: 4 weeks of DDS-1 or maltodextrin placebo once daily, with a 2-week washout
Lactobacilli and bifidobacteria in the prevention of antibiotic-associated diarrhoea and Clostridium difficile diarrhoea in older inpatients (PLACIDE): a randomised, double-blind, placebo-controlled, multicentre trial.
Lancet (2013) · Rct · n=2981
Randomised, double-blind, placebo-controlled multicentre trial in 2,981 inpatients aged 65 and over taking antibiotics, given a multistrain preparation of lactobacilli and bifidobacteria (6 × 10^10 organisms per day for 21 days) or placebo
Lactobacillus reuteri to Treat Infant Colic: A Meta-analysis.
Pediatrics (2018) · Meta analysis
Day-21 adjusted mean difference in cry/fuss time: -25.4 min/day (95% CI -47.3 to -3.5)
Treating infant colic with the probiotic Lactobacillus reuteri: double blind, placebo controlled randomised trial.
BMJ (2014) · Rct · n=167
Probiotic group cried/fussed 49 minutes MORE than placebo at 1 month (95% CI 8 to 90, P=0.02)
Probiotics to prevent infantile colic.
Cochrane Database Syst Rev (2019) · Meta analysis
No difference in new cases of colic: RR 0.46 (95% CI 0.18-1.19), low certainty
L. reuteri DSM 17938 has a higher evidence score (6/10 vs 5/10) and wins in 2 of 3 categories.
Both L. acidophilus and L. reuteri DSM 17938 score equally (55) for improve digestion.
No documented interaction was found in the data searched. This does not establish that this exact combination is safe.
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.