Understanding Probiotics: CFU, Strains, and Choosing the Right Type

What Are Probiotics?

Probiotics are live microorganisms, often bacteria, that are commonly associated with supporting a healthy balance of gut flora. They're found naturally in some fermented foods and are also widely available as standalone supplements in capsule, tablet, or powder form.

Understanding CFU

CFU stands for "colony-forming units," and it's the standard way probiotic potency is measured on a label — essentially an estimate of how many viable microorganisms are in a given serving at the time of manufacturing. CFU counts on probiotic labels can range widely, from a few billion to over 100 billion, depending on the product and its intended use.

Probiotic Strains

Probiotic products often list multiple named strains (such as various Lactobacillus or Bifidobacterium species) rather than a single generic "probiotic" ingredient. Different formulas combine different numbers and types of strains, and products marketed as "multi-strain" or "broad-spectrum" typically include a wider combination than single-strain products.

General Digestive Probiotic Formulas

Most probiotic supplements are formulated as general, everyday digestive-support products, often combined with prebiotic ingredients (which are believed to help feed beneficial bacteria). Our probiotic option from BioSchwartz is a general digestive formula providing 65 billion CFU across 13 strains, plus a prebiotic blend.

Different Categories of Probiotic Products

Not all probiotics are formulated for the same purpose. Alongside general digestive formulas, there are also probiotic products specifically formulated for women's and intimate health, which typically use different strains selected for that specific context rather than general digestive support. Our vaginal probiotic option from O Positiv is formulated specifically for this purpose, and shouldn't be treated as interchangeable with a general digestive probiotic — the two are formulated differently for different intended uses.

How to Compare Probiotic Labels

A few things are worth checking when comparing probiotic products:

• CFU count — and whether it's guaranteed through the end of shelf life or only "at time of manufacturing," which some labels specify
• Number and type of strains — single-strain versus multi-strain formulas
• Intended use — general digestive support versus a more specific formulation, such as women's or intimate health
• Additional ingredients — whether prebiotics or other supporting ingredients are included
• Storage requirements — some probiotics require refrigeration, while others are shelf-stable

FAQ

Is a higher CFU count always better?
Not necessarily — the right CFU count depends on the individual product, its intended use, and personal factors. A higher number isn't automatically more appropriate for everyone.

Can I take a general probiotic and a women's-specific probiotic together?
These are formulated for different purposes. If you're considering combining supplements, checking with a healthcare professional is a reasonable step, particularly since formulations and strains differ between general and targeted products.

Do probiotics need to be refrigerated?
It depends on the specific product — some probiotic strains are shelf-stable, while others are formulated to require refrigeration. Check your product's label for storage instructions.

What's the difference between probiotics and prebiotics?
Probiotics are live microorganisms, while prebiotics are ingredients (often fibers) that are commonly understood to help feed beneficial bacteria already present in the gut. Some products combine both.

Explore our full Digestive Health collection to compare probiotic and other digestive-support options.