By definition, adaptogens are nontoxic, nonspecific (meaning they build adaptive energy rather than exerting a specific effect), and normalizing (meaning there's a balancing bidirectional effect on physiological function). Tero Isokauppila, founder of Four Sigmatic, and registered herbalist Danielle Ryan Broida guide you through the scientific mechanisms and health benefits of the 21 most powerful species of adaptogens, from ashwagandha to chaga to...