Table of Contents
Table of Contents
I’m often asked whether probiotics actually work – or more specifically, whether the probiotics people buy are still alive by the time they take them. Unlike many supplements, probiotics aren’t inert compounds. They are living microorganisms that may provide health benefits for gut health, immune function and overall wellbeing when consumed in adequate amounts.1
So, you may wonder what happens to these live organisms during storage and delivery? With packages travelling long distances to your doorstep, it’s reasonable to wonder whether probiotics might be 'dead on arrival'.
Probiotics must be alive to impart health benefits, and they are sensitive to environmental conditions like heat, moisture and time. Read on to understand how to store and handle probiotics for peak potency, check their viability and spot signs that they may no longer be effective.
Unlike vitamins or minerals, probiotics are live cultures – microscopic organisms that must be viable to deliver health benefits. Their effectiveness depends not just on what’s inside the capsule, but on how many of those organisms survive until consumption.
During manufacturing, probiotic products are carefully formulated and often freeze-dried to stabilise the bacteria. However, once packaged, these organisms remain sensitive to environmental stressors, with heat posing the greatest threat.
Probiotics may be vulnerable during transport due to:
Even well-designed probiotics can lose potency if exposed to excessive heat for extended periods. For this reason, many high-quality probiotics list the number of Colony Forming Units, or CFUs, on their packaging.
Colony Forming Units (CFUs) are the number of living bacteria in a probiotic product. This number indicates how many microorganisms are capable of reproducing and forming colonies in the gut.
Importantly, not all CFUs are equal. A probiotic may list '10 billion CFUs', but the critical question is when? Some products list CFUs at the time of manufacture, while others guarantee CFUs to the expiration date. The latter is far more meaningful because probiotics naturally lose viability over time, especially when exposed to heat.
High temperatures can rapidly reduce CFUs. And since delivery trucks can exceed temperatures of 120 to 130 degrees Fahrenheit during summer months, survival of probiotic bacteria depends on how they’re stored and transported. A product that starts with high CFUs may deliver far fewer by the time you take it, if conditions aren’t controlled.
Some, but not all, probiotics are shelf stable. Many high-quality probiotics use specialised, freeze-dried strains that remain stable at typical room temperatures between 68 and 77 degrees Fahrenheit. These shelf-stable strains don’t require refrigeration.
Still, 'shelf stable' doesn’t mean heat-proof. Even shelf-stable probiotics are susceptible to degradation in high temperatures. In laboratory testing, shelf-stable probiotics are kept within a narrow temperature range. However, real-world exposure often involves transit in hot delivery trucks, storage in warehouses without climate control and time spent in the sun on doorsteps upon delivery. Even shelf-stable formulations can lose CFUs under these conditions.
Sensitive supplements, like probiotics and nutrients like vitamin C and B vitamins, should be handled properly to ensure potency. Best practice includes:
As a consumer, one of the best ways to ensure your supplements maintain their potency is to always purchase directly from reputable brands or vendors like iHerb that use climate-controlled warehouses, have quick turnover and hold Good Manufacturing Practice (GMP) or International Organization for Standardization (ISO) registrations.
Most of us don’t have access to laboratory testing, but there are several practical ways to evaluate probiotic quality.
This ensures the probiotics are formulated to maintain potency over time – not just at the time of manufacture.
High-quality probiotics list the genus, species and strain of all bacteria in the supplement.
Programmes like iTested provide independent quality checks for identity, purity and potency.
Certain bacterial strains ferment when poured from their capsule and mixed with milk. This isn’t a standardised test and is not a reliable measure of potency, but it may help demonstrate whether the bacteria are alive.
Once your probiotics arrive, proper storage helps prolong their shelf life and viability. To get the full benefits of your probiotics, follow these guidelines for storage:
You can’t see CFUs directly, but there are warning signs that your probiotics may have degraded. Beyond checking supplements to ensure they haven’t expired, watch for any changes in smell or appearance, such as discolouration, clumping or unusual odours. Humidity can damage freeze-dried bacteria, reducing viability – so discard probiotics if you see any moisture inside the container.
Finally, if your probiotics have been left in the heat (like in a hot car or post box), their potency may be compromised even if they look normal. And while expired or 'dead' probiotics don’t pose any harm, they won’t provide any benefit, either.
When it comes to probiotics, quality isn’t just about what’s on the label – it’s about the viability of the strains from manufacturing to your microbiome. That’s why proper formulation, handling and storage practices are essential.
Even the best probiotic can lose effectiveness if it’s exposed to excessive heat or poor conditions. Always choose supplements from high-quality brands with third-party testing and purchase from reputable retailers, like iHerb, that guarantee supplements are stored in climate-controlled warehouses, have high turnover and hold GMP or ISO registrations to ensure quality.
Remember, probiotics are living organisms. Treat them accordingly, and they’re far more likely to deliver the health benefits you’re looking for.
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DISCLAIMER: These statements have not been approved by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent disease.
