We have our classic shelf-stable probiotics and our “cool” probiotics which are refrigerated. See how a patented, dessicant bottling process keeps moisture out and potency in. Our roots are in probiotics, ever since our first probiotic, Primal Defense® was created. Containing Homeostatic® Soil Organisms or HSOs, hardy organisms that are shelf stable and survive stomach acid. Primal Defense was revolutionary, and remains a unique probiotic formula. While Primal Defense has always been shelf stable, many important, health promoting probiotics are not and can lose their potency—literally dying off—when placed on the shelf instead of being refrigerated. As time went on, we realized the need for various probiotics for overall health, so we creatively sought to preserve them effectively, which led to our refrigerated probiotics with the Arrive Alive!™ promise.