The term adaptogen was coined by Soviet pharmacologist Nikolai Lazarev in 1947. He defined it as a substance that increases non-specific resistance to stress — physical, chemical, or biological — without disrupting normal bodily functions.
The Three Criteria
For a plant to be classified as an adaptogen it must: (1) be non-toxic in normal doses, (2) produce a non-specific response that increases resistance to multiple stressors, and (3) have a normalising effect — reducing stress when it is high, and stimulating when energy is low.
The HPA Axis
Adaptogens work primarily by modulating the HPA axis (hypothalamic-pituitary-adrenal), which controls cortisol release. Under chronic stress, cortisol dysregulation leads to fatigue, immune suppression, and mood disorders. Adaptogens help recalibrate this axis toward equilibrium.
They Take Time
Unlike acute anxiolytics (benzodiazepines) or stimulants, adaptogens require 4–8 weeks of consistent use to show their full effect. They are tonic herbs — taken daily as a long-term strategy, not a quick fix.