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Supplement

Lactobacillus Casei

Lactobacillus casei is a probiotic bacterium found in the gut and in fermented foods, where it helps break down food and interacts with the immune system. People mostly look at it for immune health, but the evidence is limited: a small study of 28 people found that the inflammation marker CRP changed, though which way is unclear. Other small studies found no clear difference in blood glucose or in immunity during upper respiratory infections.

Best evidence
Grade C
Conditions studied
4
Outcomes
21
Graded outcomes
0014

Evidence by condition

  • Strong
  • Moderate
  • Limited
  • Very limited

4 conditions

Immune Health

Immune Health: outcomes studied for Lactobacillus Casei
GradeOutcomeEffectSizeStudiesPeopleStudies list
C-Reactive Protein (CRP)

Small Increase

Improves (the measure goes down)Small effect28 people
Blood glucose

No effect

NoneNo effect28 people
Immunoglobulin AImproves (the measure goes up)2 studies84 people

Studies that measured immunoglobulin a

Intestinal PermeabilityImproves (the measure goes up)1 study28 people

Studies that measured intestinal permeability

ImmunityImproves (the measure goes up)28 people
Immunoglobulin GImproves (the measure goes up)84 people
TriglyceridesImproves (the measure goes down)28 people
Upper Respiratory Tract Infection RiskChanges; see studies84 people
White Blood Cell CountImproves (the measure goes up)84 people

Upper Respiratory Tract Infection

Upper Respiratory Tract Infection: outcomes studied for Lactobacillus Casei
GradeOutcomeEffectSizeStudiesPeopleStudies list
Immunity

No effect

NoneNo effect47 people
Immunoglobulin AImproves (the measure goes up)2 studies131 people

Studies that measured immunoglobulin a

Immunoglobulin GImproves (the measure goes up)84 people
Upper Respiratory Tract Infection RiskChanges; see studies131 people
White Blood Cell CountImproves (the measure goes up)84 people

Digestive Health

  • Blood glucose
  • Intestinal Permeability: improves
  • Immunity: improves
Digestive Health: outcomes studied for Lactobacillus Casei
GradeOutcomeEffectSizeStudiesPeopleStudies list
Blood glucose

No effect

NoneNo effect28 people
Intestinal PermeabilityImproves (the measure goes up)1 study28 people

Studies that measured intestinal permeability

ImmunityImproves (the measure goes up)28 people
WeightImproves (the measure goes down)28 people

Lower Respiratory Tract Infection

  • Immunity
  • Immunoglobulin A: improves
  • Upper Respiratory Tract Infection Risk: changes; see studies
Lower Respiratory Tract Infection: outcomes studied for Lactobacillus Casei
GradeOutcomeEffectSizeStudiesPeopleStudies list
Immunity

No effect

NoneNo effect47 people
Immunoglobulin AImproves (the measure goes up)2 studies47 people

Studies that measured immunoglobulin a

Upper Respiratory Tract Infection RiskChanges; see studies47 people

Key findings

  • C-Reactive Protein (CRP)Immune HealthImproves (the measure goes down)
  • Blood glucoseImmune Health
  • ImmunityUpper Respiratory Tract Infection

Shop Lactobacillus Casei

Third-party tested Lactobacillus Casei products. The evidence above is limited, so read it before you buy.

  • Grade C

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Studies cited

3 studies from PubMed

  1. The influence of probiotic supplementation on gut permeability in patients with metabolic syndrome: an open label, randomized pilot studyEur J Clin Nutr · PMID 22872030
  2. Daily probiotic's (Lactobacillus casei Shirota) reduction of infection incidence in athletesInt J Sport Nutr Exerc Metab · PMID 21411836
  3. Effect of a probiotics supplementation on respiratory infections and immune and hormonal parameters during intense military trainingMil Med · PMID 17937368