special subjects
Involuntary Weight Loss
Pathophysiology of Involuntary Weight Loss
Weight loss results when more calories are expended than taken in (ingested and absorbed). Disorders that increase expenditure or decrease absorption tend toincreaseappetite. More commonly, inadequate caloric intake is the mechanism for weight loss and such patients tend to havedecreasedappetite. Sometimes, several mechanisms are involved. For example, cancer tends to decrease appetite but also increases basal caloric expenditure by cytokine-mediated mechanisms. 