Raising the Bar on Probiotic Testing: From CFUs to dPCR “Viable Cells”

Probiotics are a critical component of AG1 Next Gen. These “good bacteria” help with everything from digestion to immune health. It’s critical for people to really know what’s in their probiotics and if it contains the live cells it claims on the label. Live cells are important because only living probiotics can survive in the gut, grow, and do the beneficial work they’re meant to, like balancing the microbiome and supporting digestion and the immune system. Without live cells, the product can’t deliver the full health benefits that define a quality probiotic.

AG1 is always evolving alongside new scientific findings and methodologies in order to reflect the latest advancements in research and technology. Our next leap forward is how we measure and test the live probiotic content in AG1 Next Gen: we’re moving to a DNA-based method called digital polymerase chain reaction (dPCR) — reported on the label as “viable cells.” This switch delivers a clearer and precise picture of the live probiotics you get in every scoop.

Why are we changing how we measure probiotics?

For years, most companies have measured probiotic content using colony-forming units (CFUs), and it remains a common approach. CFUs are counted by growing these good probiotic bacteria on a petri dish and literally counting the visible colonies as an estimate of the live probiotics in the product. This method, while useful, has key limitations:

• Speed: It can take days or even weeks for colonies to grow, depending on the species and strains (Anand, 2011).
• Strain bias: When probiotics are counted using CFUs, the test usually only sees the species, not the exact strain (Shehata et al., 2023). So it can claim “this is Lactobacillus acidophilus,” but does not delineate down to the specific strain level — for example, strain GG. That means if a product has multiple strains, the test often ends up giving one total number instead of a breakdown for each strain. This is important because probiotic health benefits are often strain-specific. For example, Granny Smith and Fuji are both apples of the same species, yet taste very different. Similarly, Lactobacillus rhamnosus GG and HN001 are strains of the same probiotic species, but their studied health benefits are not the same.
• Undercounting: Some cells won’t replicate or simply won’t grow in standard lab conditions, so the tally can miss them (Davey, 2011). And, when multiple strains are present, some may thrive while others struggle to grow, depending on their own metabolic needs.
• Accuracy: Plate enumeration is known to have a high rate of variability depending on the bacteria being measured, based on how colonies grow (Jongenburger et al., 2010).
• Nutritional interference: In complex formulas with many ingredients, probiotic cultivation can be “interfered” with by creating nonsuitable growth conditions in a lab, preventing them from growing in CFU tests (Zarecki et al., 2014).

In complex, nutrient-dense powders like AG1, these limitations make a difference. It is time for improvements based on advancing technologies.

Introducing dPCR — a precise DNA-level headcount

dPCR (digital PCR) is like giving probiotics a DNA check-in. It uses advanced tools to identify and count specific strains with incredible accuracy. Unlike older methods that can take days and miss certain cells, dPCR delivers results with elevated precision and accuracy; it even counts live cells that aren’t actively growing.

Why this is important:

• Confirms the exact strains in your product
• Measures with single-cell accuracy
• Detects hard-to-measure live cells

Think of it as upgrading from a black and white TV to a high-definition LED for microorganisms. Ultimately, increased accuracy not only verifies exactly what you’re putting in your body, but it also reinforces the gut health benefits you can expect to feel.

What does this mean for the probiotics in AG1?

1. Same trusted dose, now measured with advanced technology
   The formula hasn’t changed. AG1 Next Gen delivers 10 billion viable cells per serving.
2. Even greater confidence batch-to-batch
   Because dPCR sees every one of our viable probiotic cells (including those that might fail to form colonies in the lab setting), it tightens our quality checks and further ensures label accuracy batch after batch.
3. A transparent, science-forward signal
   Research shows “viable cells” will become the new benchmark (Kiefer et al., 2020; Hansen et al., 2020). By moving early, AG1 continues to incorporate category-leading testing standards.

FAQ

Q: I’ve never heard of dPCR. Can I trust it?

A: dPCR is a cutting-edge DNA technology already favored in academic and diagnostic labs for its accuracy and reproducibility (Coccaro et al., 2020; Quan et al., 2018; Yin et al., 2024; Mirabile et al., 2024). We’re bringing that same rigor to your AG1 morning routine (Kiefer et al., 2020; Hansen et al., 2020).

Q: Why haven’t more companies adopted dPCR?

dPCR is still relatively new and requires a significant investment in technology, expertise, and validation. More traditional methods can be faster or less expensive, but at AG1 we believe accuracy and precision matter, and we have a team of expert research scientists working daily to apply new technological advances. We’ve committed to transitioning to the most advanced approach available to ensure our probiotics deliver exactly what is promised.

Q: Will my gut feel any different?

A: The benefits of AG1 Next Gen remain the same — five clinically studied probiotic strains, now measured with a finer lens. AG1 Next Gen’s clinically studied probiotic strains each play a unique role in the maintenance of digestive and immune health, including regularity and bloating.

Q: How do I compare “viable cells” to a brand still listing CFUs?

A: They’re two different yardsticks. CFU tallies only colony-forming bacteria; dPCR tallies all live, strain-verified cells. Direct number-to-number comparisons don’t tell the whole story. Measuring viable cells gives a more complete picture of all the live probiotics, not just the ones that could grow in a lab test.

Q: Are CFUs inaccurate? Was I getting the wrong probiotics before?

A: CFU counts are still recognized by regulators and remain a method we’ll list on some products while the transition rolls out. You’ve always received the probiotic amounts clinically studied for effectiveness — dPCR simply verifies it with greater sensitivity.

Why This Matters to You

When shopping for probiotics, the actual probiotic content in your product makes a difference:

• The exact strains matter
• Whether they’re alive and active or dormant and non-viable impacts their metabolic activity
• Whether they’re in the amounts needed to be effective

The advancements in dPCR enable that level of transparency. Plus, as probiotic science evolves, it has been underscored that strain matters. Not all probiotic products are created the same. dPCR helps ensure you’re getting what you think you are.

This is another way we’re investing in transparent, next-generation science behind AG1.