Identify the strain, not just the broad category
A probiotic comparison should record the complete microorganism identification supplied by the label. Genus, species, and strain describe progressively more specific information; a broad probiotic name may leave important details unresolved.
What CFU tells you
CFU stands for colony-forming units. The number is a way of describing viable microorganisms, not a universal score of effectiveness. Compare the specific strains and the question the product is intended to address before judging its CFU statement.
Read the timing and storage statement
- Check the expiry or use-by date.
- Record the label’s storage instructions.
- Note what the CFU statement says about when the count applies.
- Record undisclosed strain information as missing.
Do not add unlike products into one score
Two products listing the same CFU total may still describe different organisms, strains, and preparations. A combined number across a blend does not necessarily show the amount of each strain. Keep the label fields separate rather than ranking products by one large number.
Food and supplement labels are different comparisons
A fermented food, a food with live cultures, and a probiotic capsule should not be assumed to provide the same preparation. Read what the label actually identifies and whether evidence is relevant to the stated intended use.
Personal suitability
People with serious illness or a weakened immune system should discuss probiotic use with a clinician. This guide does not select a strain or dose for a medical condition.
Sources and evidence
NIH Office of Dietary Supplements probiotic fact sheet. Ingredient references explain general information; they do not endorse products listed here.
Updated · Editorial approach