Streptococcus thermophilus
Also known as: S. thermophilus, Streptococcus salivarius subsp. thermophilus, St-21, TH-4, yogurt culture
Streptococcus thermophilus is one of the two mandatory yogurt starter cultures and a source of the enzyme lactase (beta-galactosidase). It is generally included in blends to support lactose digestion and to complement Lactobacillus and Bifidobacterium strains rather than as a stand-alone probiotic. Human data are modest and mostly from fermented dairy; a small randomized study examined live cultures and lactose digestion in adult lactose malabsorbers. It is inexpensive, robust to freeze-drying, and stable in capsule and powder products.
Research summary
Delivers bacterial lactase to the small intestine and produces lactic acid; studied for support of lactose digestion.
Dosage
Daily amounts, of compound. CFU shown in billions.
| Lowest studied | Typical range | Highest studied | Upper limit |
|---|---|---|---|
| 1 B CFU | 1–5 B CFU | — | — |
Amounts are in billions of CFU (enter 2 for 2 billion). Raw-material weight assumes a 100 billion CFU/g concentrate (10 mg per billion CFU); manufacturers add a 20–50% CFU overage at fill so the label claim holds through shelf life, and the label should state whether CFU are guaranteed at manufacture or at expiry. Dose range reflects typical blend inclusion levels rather than stand-alone trials.
Standardization: Strain-designated freeze-dried culture; CFU per gram on CoA
Source material: freeze-dried culture
As supplied: Assumes 100 billion CFU/g concentrate (10 mg per billion CFU); adjust to supplier CoA.
Format suitability
- Capsule
- Powder
- Tablet
- Softgel
- Gummy
- Liquid
Heat- and moisture-sensitive vegetative cells; capsule or dry powder only.
Formulation notes
Usually cultured on dairy-based media; confirm dairy-free status with the supplier if the finished product is labeled dairy-free. Separate from antibiotic dosing by at least two hours.
Sources
Related ingredients
Probiotic Blend (Multi-Strain)
ProbioticA generic placeholder for a multi-strain probiotic blend, typically combining several Lactobacillus and Bifidobacterium species and sometimes Streptococcus thermophilus or a Bacillus spore.
Typical: 10–50 B CFU
Magnesium Oxide
MineralThe most concentrated magnesium source at about 60% elemental magnesium, which is why it dominates in multivitamins and small tablets.
Typical: 200–350 mg
Inulin (Chicory Root Fiber)
PrebioticInulin is a soluble, fermentable fructan fiber extracted mainly from chicory root, though it also occurs in Jerusalem artichoke, agave, and onions.
Typical: 5–10 g
Piperine (Black Pepper Extract 95%)
BotanicalThe pungent alkaloid isolated from black pepper fruit, used in tiny amounts to raise the absorption of other ingredients rather than for its own effects.
Typical: 5–20 mg
Greens Blend (Generic)
OtherA generic greens blend is a placeholder for the dried plant powders typical of greens products: cereal grasses such as wheatgrass and barley grass, spirulina and chlorella, leafy vegetables like spinach and kale, and often fruit or vegetable extracts.
Typical: 3–10 g