Our goal in this article is to evaluate and compare the influential concepts of homeostasis and allostasis as they relate to physiological regulation. A particular focus is on whether either of these two models adequately explains the regulatory process. We begin by orienting the reader to the organization, definitions and positions taken in our analysis, and subsequent sections discuss the issues that we contend distinguish homeostasis and allostasis. We conclude that homeostasis and allostasis each has an important role and that research and theorizing on them has been hampered by lack of a clear operational definition of allostasis.
In broad terms, we suggest that allostasis be considered a dysregulatory (or disordered) form of physiological regulation that involves effector loops that over-respond in magnitude or duration and/or that compete concurrently with other effectors.