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Head-to-head evidence comparison — which supplement is right for you?
B. infantis 35624 vs L. casei Shirota: L. casei Shirota has the stronger overall evidence (5 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. casei Shirota wins 1 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Too few graded studies
Top outcomes
Verdict
Too few graded studies
Top outcomes
Shared outcomes (1)
Outcomes where both B. infantis 35624 and L. casei Shirota have evidence — compare verdict strength side-by-side.
1 x 10^8 CFU (100 million) daily — the dose that won the only head-to-head dose comparison; 1 x 10^10 CFU also beat placebo in a separate trial, so higher doses are not ruled out
Any time of day
Freeze-dried capsule standardized to 35624 at 1 x 10^8 CFU
One 65-100 mL bottle of the fermented milk drink daily, delivering roughly 6.5 x 10^9 to 1 x 10^11 CFU depending on the product. Doses across trials span this whole range with no dose-comparison study to separate them.
Any time of day
Fermented milk drink containing L. casei Shirota (Yakult), 65-100 mL daily
4 weeks
4 weeks
n/a
n/a
4 weeks
2 weeks
2-12 weeks
8 weeks
Efficacy of an encapsulated probiotic Bifidobacterium infantis 35624 in women with irritable bowel syndrome.
Am J Gastroenterol (2006) · Rct · n=362
1 x 10^8 CFU significantly superior to placebo AND to all other doses for the primary endpoint of abdominal pain
Lactobacillus and bifidobacterium in irritable bowel syndrome: symptom responses and relationship to cytokine profiles.
Gastroenterology (2005) · Rct · n=77
Beat placebo on composite score and on abdominal pain, bloating/distention and bowel-movement difficulty for most treatment weeks
Efficacy of Bifidobacterium infantis 35624 in patients with irritable bowel syndrome: a meta-analysis.
Curr Med Res Opin (2017) · Meta analysis
Single-strain 35624 had no effect on abdominal pain, bloating/distention, or bowel-habit satisfaction
Efficacy of daily intake of Lactobacillus casei Shirota on respiratory symptoms and influenza vaccination immune response: a randomized, double-blind, placebo-controlled trial in healthy elderly nursing home residents.
Am J Clin Nutr (2012) · Rct · n=737
PRIMARY ENDPOINTS ALL NULL: no effect on days with respiratory symptoms, probability of respiratory symptoms, or post-vaccination antibody titre
Probiotics and synbiotics in chronic constipation in adults: A systematic review and meta-analysis of randomized controlled trials.
Clin Nutr (2022) · Meta analysis
Probiotics overall increased stool frequency (SMD 0.71, 95% CI 0.37-1.04, p<0.00001) — but the effect was driven by Bifidobacterium lactis, 'not mixtures of probiotics, Bacillus coagulans Unique IS2 or Lactobacillus casei Shirota'
A study into the effect of Lactobacillus casei Shirota in preventing antibiotic associated diarrhoea including Clostridioides difficile infection in patients with spinal cord injuries: a multicentre randomised, double-blind, placebo-controlled trial.
EClinicalMedicine (2021) · Rct · n=359
PRIMARY ENDPOINT NULL: antibiotic-associated diarrhoea at 30 days 45% vs 42.1% (RR 1.071, 95% CI 0.8-1.4, p=0.639)
L. casei Shirota has a higher evidence score (5/10 vs 5/10) and wins in 1 of 3 categories.
For improve digestion, B. infantis 35624 has a higher relevance score (58 vs 52).
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.