What's the difference between shelf-stable and refrigerated probiotics?

Comment: Amy Fitzpatrick, RD, dietitian and consultant to the dietary supplements industry.

While it would seem that refrigerated products are more likely to retain their potency, some nonrefrigerated probiotic pills, particularly those with specific technology to protect the bacteria from heat, light and oxygen, can also remain viable for an extended period of time.

Manufacturers of high-quality, nonrefrigerated probiotic products place a guarantee of probiotic content at the time of manufacture. They should also include an expiration date. Whether selecting a refrigerated or nonrefrigerated product, retailers should steer customers toward a pill with a high dose of probiotics, and preferably one that also contains probiotics. This helps ensure viable amounts of bacteria remain at the time of purchase. I look for pills that contain a minimum of 1 billion colony-forming units per dose, but I prefer 10 billion CFUs or more.

The reality with probiotics is that the choice is not just between what’s in the fridge and what’s on the shelf.