Supplement analysis backed by scientific evidence · PT

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Limited evidenceGut health

Streptococcus Thermophilus

The yogurt starter culture. Its lactase helps digest lactose — but that is documented for live yogurt, not for capsules, and probiotic supplements have not shown a reliable benefit in lactose intolerance.

Evidence last reviewed: August 2026

What the science says

  • Lactose digestion from yogurt Moderate evidence

    A review of the mechanism summarizes consistent human evidence that live yogurt cultures, S. thermophilus and L. bulgaricus, deliver bacterial lactase into the intestine and improve lactose digestion. An in vivo comparison of strains found the effect depends on which cultures the fermented milk contains and on their survival.

  • Probiotic capsules for lactose intolerance Limited evidence

    A systematic review of probiotics for adult lactose intolerance concluded that supplements do not reliably reduce symptoms, in contrast to consuming live yogurt itself.

  • Gut symptoms as a single strain Limited evidence

    S. thermophilus is nearly always studied inside multi-strain yogurts or formulas, so there is no clean evidence for it alone.

Dosage & safety

Studied doseNo established supplement dose; products supply 1–10 billion CFU. For lactose digestion, the studied "dose" is a serving of unheated live yogurt eaten with the lactose-containing meal.
SafetyVery safe, with a long food history. It is not a substitute for lactase enzyme tablets if you need reliable lactose digestion. Standard caution for live cultures in severe immunosuppression.

Scientific references

Where to buy

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