How to Read a Probiotic Label
A probiotic label is most useful when it lets you identify exactly what organisms you are taking and how the product should be stored and used.
Species vs strain
A label might name a species such as Lactobacillus gasseri. Research can be specific to an even narrower strain, often shown by letters and numbers after the species name.
CFUs
Colony-forming units estimate viable microorganisms. Do not treat the largest CFU number as a universal quality score. More is not necessarily better.
Serving size
Check whether the listed amount applies to one capsule, two capsules or a daily serving. This matters when comparing products.
Storage
Follow label directions for temperature, moisture and refrigeration. Viability can be affected by handling and storage.
Other ingredients
Review capsules, fillers, prebiotics, botanical extracts and allergen statements. Multi-ingredient formulas can be harder to compare with research on a single strain.
Claims
Structure/function marketing language is not the same as FDA approval of a disease-treatment claim. NCCIH explains that dietary supplements do not require FDA approval before marketing in the same way drugs do.