Concept of the Week

Homeostasis: This term refers to the body's ability to maintain relatively stable internal conditions in the face of continual change it its environment. There are a great many variables that need to be controlled and kept within optimal ranges in order for the trillions of cells that make up our bodies to continue functioning properly. Adequate blood levels of nutrients and gases must be maintained; heart activity and blood pressure must constantly be monitored and adjusted; wastes must not be allowed to accumulate in body tissues; body temperature must be maintained; electrolyte levels must be tightly controlled; blood pH must be kept within narrow limits; and on and on. And, under normal conditions, the body does an excellent job of monitoring and controlling all of these factors and more!

The body is said to be in homeostasis when its needs are being met and it is functioning smoothly. This is an extraordinarily complex task, and every single organ system has its own particular role to play in maintaining the constancy of the internal environment. Although the literal translation of homeostasis is "unchanging," do not fall into the trap of assuming that these important variables are maintained at a rigid, constant level. Homeostasis implies a dynamic state of equilibrium. That is to say, internal conditions do fluctuate, but are only allowed to do so within a relatively narrow range.

Homeostasis is so crucial, that most disease can be regarded as a disturbance of homeostasis (homeostatic imbalance).