the term was proposed by the British psychologist Peter Warr (1987) to explain the relationship between the characteristics of the psychosocial environment (especially the work environment) and a person’s mental health. Warr compares environmental factors that affect mental health to vitamins in the human body: just as vitamins are essential for health, these factors are also important for psychological well-being. Just as the effects of vitamins vary from species to species (some are harmful in excess, while others are harmless), so too do the characteristics of the job or the environment.