Liquid supplements will generally come with instructions to refrigerate after opening, and they have a short shelf life of 30 to 90 days typically (versus the two to three years other supplement forms have).

While some probiotic strains and formulations require refrigeration, others absolutely do not. Some probiotics (like mindbodygreen’s probiotic+) are designed to be shelf-stable. And if that’s the case, refrigerating them can mess with the quality, stability, and active ingredients in the supplement. 

And remember, probiotics deliver live microorganisms to help colonize the gut, so storing the supplement incorrectly can (inadvertently) create an environment that those organisms can’t survive in.    

“The supplements that do not explicitly state the need for refrigeration in their use or storage instructions should never be refrigerated,” says Ferira. “It’s delightfully black and white.”