What is CFU In Probiotics? CFU Meaning, Health Implications

what is cfu in probiotics

Lately, we’ve been hearing a lot of talk about probiotics in food and probiotic supplements, and how good they are for health.

And all that is quite simple, but what is this CFU count that’s often mentioned along with probiotics?

What is CFU in probiotics and how does it affect our bowel movements and overall health?

Let’s discuss the meaning, significance, and role of CFU in probiotics or probiotic supplements for maintaining health.

All You Need To Know about CFU In Probiotics

What is CFU meaning?

CFU stands for colony-forming units.

In terms of probiotics, it is a measurement unit for the number of active, living cells (probiotic bacteria in this case) that are further capable of reproducing into more cells, per serving of probiotic supplement containing probiotics.

The significance of CFU in probiotic strains

In simple words, our bodies contain both good gut bacteria and bad gut bacteria.

When we get infected and fall sick, the bad bacteria are actively at work, and that’s when the good gut bacteria have to step in and fight them, to clear our systems and help us regain health.

Probiotic gut bacteria (which is in fact good bacteria) are largely instrumental in health maintenance, because they contain the beneficial bacteria we need, particularly when it comes to combatting gut-related infections and diseases such as Irritable Bowel Syndrome (IBS), dysentery, diarrhea, and constipation.

Understanding probiotic bacteria count

The count of colony-forming units of a bacteria/yeast can be calculated in the laboratory, where the bacterial culture is put into a petri dish (an agar plate in this context), and the numbers of colonies that show up on the petri dish are the ones that you actually end up ingesting when you take the probiotic.

What do CFUs (colony forming units) do for human health?

CFUs or colony-forming units, a vital component of any probiotic supplement, work their magic best in the gastrointestinal tract, which can also be understood as the gut microbiome where beneficial bacteria fight to do good over any harmful gut bacteria or any other bacterial cells that may enter the system.

A good count of colony-forming units of gut bacteria protects the immune system by actively resisting any attempts of colonization by harmful bacteria, assisting smoother bowel movements, and helping strengthen the gut barrier- again, an important boost to immune function.

Oftentimes, scientific research and clinical trials have also revealed that the administration of a probiotic supplement containing beneficial bacteria, after a course of antibiotics has been successful in helping restore the equilibrium of the gut microbiome.

This is due to the prolific presence of CFUs in probiotics. 

Although probiotics are made of a variety of viable microorganisms, a vast majority used in supplements or found in food sources, contain primarily the Lactobacillus bulgaricus and the Streptococcus thermophilus among others.

The Bifidobacterium species of microorganism is also seen often in probiotic supplements. 

Sources of CFU in probiotics

Probiotics or probiotic bacteria found in fermented foods contain a significant CFU count for gut health.

These include some simple foods we are generally familiar with, like yogurt, cultured milk, several kinds of wine, beer, and aged cheese; and less common but increasingly popular sources like kombucha, kefir, tempeh, sauerkraut, miso, and kimchi.

Choosing the right probiotic supplements for gut health

Today, with advancements in scientific research, there are lots of probiotic supplements available in the market to choose from- in powder, liquid, or even capsule form, as per your preference.

Most will not do any harm to human health if taken without consulting a physician as well, but it is highly recommended to consult your doctor before you take probiotics or give doses to children.

It is imperative that when selecting a probiotic supplement with good bacterial cells, you should try to choose a multi-strain variant, since you want different kinds of probiotic bacteria to be at work in your gut when you ingest them, for a strong immune system.

Further, a lot of capsules and chewable tablets for probiotic bacteria don’t actually contain as much CFU as they claim, and often the good bacteria or probiotic variant that need to die before being ingested.

So be sure to assess the given count of probiotic bacteria well. 

When you take probiotics in the form of natural food sources, you can look up the estimated count of probiotic variants, but if you are taking a probiotic supplement, you can check the supplement facts label on the bottle/container for the exact count in that particular supplement.

This may either be displayed as 10 or 20 billion CFU or in the exponential form such as 1 x 1010 to denote 10 billion CFU.

However, as helpful as this is, be keener still to search the label for a mention of what the count of CFU is likely to be as the product is nearing its expiry date, as opposed to counting at the time of manufacturing.

Because, again, that is exactly how many viable cells you will take in when you’re consuming the probiotic.


CFU stands for colony-forming units, so these are the guiding forces present in probiotics as important components.

While CFUs of bacteria perform many useful functions for the immune system and for gut health, making probiotic intake necessary on the regular, there is no guarantee that a higher number of colony-forming units will provide better results.