- We all know innately that our stomachs affect our entire self. Our gut biome affects our brain health as most of our serotonin is produced in the gut. The gut is also a crucial part of our immune system, too. So Good Wolf ferments the base for the Refreshers slowly and naturally to produce countless bacteria. We infuse 2 billion supplement-grade probiotics in every single can. Rest assured, you’re getting a powerful probiotic beverage.