«Hormesis is any process in a cell or organism that exhibits a biphasic response to exposure to increasing amounts of a substance or condition. Within the hormetic zone, there is generally a favorable biological response to low exposures to toxins and other stressors. Hormesis comes from Greek hórmēsis "rapid motion, eagerness", itself from ancient Greek hormáein "to set in motion, impel, urge on". Hormetics is the term proposed for the study and science of hormesis.
In toxicology, hormesis is a dose response phenomenon characterized by a low dose stimulation, high dose inhibition, resulting in either a J-shaped or an inverted U-shaped dose response. Such environmental factors that would seem to produce positive responses have also been termed "eustress". The hormesis model of dose response is vigorously debated. The notion that hormesis is important for chemical risks regulations is not widely accepted.
The biochemical mechanisms by which hormesis works remain under laboratory research and are not well understood.» (wikipedia)
Some prooflinks can be taken from here https://youtu.be/SHoUiCKqwR0?t=1522