The allostatic load is “the wear and tear on the body” which grows over time when the individual is exposed to repeated or chronic stress. It represents the physiological consequences of chronic exposure to fluctuating or heightened neural or neuroendocrine response that results from repeated or chronic stress. The term was coined by McEwen and Stellar in 1993.
It is used to explain how frequent activation of the body’s stress response, essential for managing acute threats, can in fact damage the body in the long run. Allostatic load is generally measured through a composite index of indicators of cumulative strain on several organs and tissues, but especially on the cardiovascular system.