Skip to content

Gut label guide

How to decode probiotic strains, CFU, and labeled dose

A probiotic label makes several checkable claims about strain identity, dose, viability, and how closely the formula matches the research.

Last reviewed: 2026-09-01Focus: probiotics, strains, CFU, bundle claims

The quick read

What the evidence says

Bottom line

Which strains, how much in one serving. With those two facts you can judge whether the claim on the front is plausible, and without them you cannot. NCCIH probiotics: what you need to know NIH ODS probiotics fact sheet FDA dietary supplement labeling guide

A colony-forming unit (CFU) count states a quantity, but without strain names it cannot be linked to strain-specific evidence. NCCIH probiotics: what you need to know FTC health products compliance guidance

The strain question

Different strains behave differently in research. A claim that withholds strain identity has withheld the one detail that would let anyone check it. NCCIH probiotics: what you need to know FDA 101 dietary supplements

A checkable label lists strains, CFUs, and serving size, and states whether the viable count is guaranteed through the end of shelf life. NCCIH probiotics: what you need to know NIH ODS probiotics fact sheet FDA dietary supplement labeling guide

People who are seriously ill or immunocompromised need clinician supervision for probiotic use. Severe or fatal infections have occurred in premature infants given probiotics, so neonatal use belongs under medical supervision. NCCIH probiotics: what you need to know NIH ODS probiotics fact sheet

How this shows up in a NutriScore score

NutriScore rewards probiotic and prebiotic products when strain names are specific and dosing is visible. NCCIH probiotics: what you need to know

The score falls when a broad gut claim sits on top of an unlabeled blend. FTC health products compliance guidance FDA supplement claim substantiation guidance

What to check on the label

Strains

Match the claim to specific strain names, not to the phrase probiotic blend.

Dose clarity

Confirm the CFU count and units are given per serving.

Claim spread

Reject one blend claim stretched across sleep, mood, immunity, and digestion at once.

Sources

  1. NCCIH probiotics: what you need to know: https://www.nccih.nih.gov/health/probiotics-what-you-need-to-know
  2. NIH ODS probiotics fact sheet: https://ods.od.nih.gov/factsheets/Probiotics-HealthProfessional/
  3. FDA dietary supplement labeling guide: https://www.fda.gov/food/dietary-supplements-guidance-documents-regulatory-information/dietary-supplement-labeling-guide-chapter-iv-nutrition-labeling
  4. FTC health products compliance guidance: https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance
  5. FDA supplement claim substantiation guidance: https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-substantiation-dietary-supplement-claims-made-under-section-403r-6-federal-food
  6. FDA 101 dietary supplements: https://www.fda.gov/consumers/consumer-updates/fda-101-dietary-supplements

Keep reading

How this article was made

NutriScore has not commissioned independent clinical review of this article.

Read the editorial policy and scoring methodology. Sources favor primary canon, regulators, product labels, and peer-reviewed research; reputable secondary reporting is identified when used.

Corrections: send corrections or updated label/source evidence to support@nutriscore.fit or use the contact page.

Sources: 6 entries, all primary canon, last reviewed 2026-09-01.

For research and educational purposes only. Not medical advice.