What do CFUs mean on a probiotic label?
CFU stands for Colony-Forming Unit—and it’s basically the way probiotics are measured.
CFU is the number of live, active microorganisms in each dose (usually per capsule or per serving of food). So when a label says “10 billion CFU,” it means there are 10 billion live bacteria or yeast cells capable of reproducing and forming colonies.
- More CFUs ≠ always better. Some conditions may benefit from higher doses (like 10–100 billion), but others do well with lower doses.
- It’s not just about quantity—strain specificity and survival to the gut matter just as much, if not more.
- CFUs should ideally be guaranteed at the time of expiration, not just at manufacturing (some die off over time).
Here are some tips for selecting Probiotics and CFUs
Look for labels that say something like:
“10 billion CFU guaranteed at expiration”
rather than
“30 billion CFU at time of manufacture”
The second one might have way fewer live bacteria by the time you actually take it.
Want help matching CFU counts and specific strains to health goals (like for digestion, mood, immunity, etc.)?
#Probiotics #Colony-Forming Units (CFUs) #Live, active Bacteria #Labels