For more than two centuries, scientists have observed and reported the increase in energy expenditure that occurs during meal digestion. From the minute copepod to the horse, this reported ‘‘cost of digestion’’ has been described, quantified, and experimentally investigated over a wide array of invertebrate and vertebrate taxa.
Originally coined specific dynamic action (SDA) from Max Rubner’s descriptions, and later acquiring the additional labels of heat increment of feeding (HIF), diet-induced thermogenesis (DIT), and thermic effect of feeding (TEF), this postprandial physiological phenomenon is considered an obligatory metabolic response of meal digestion and assimilation.
Much of the attention in SDA has historically been driven by the desire to identify its underlying mechanisms and the various determinants responsible for the variation in the magnitude and duration of this metabolic response. Defined numerous times, an accepted working definition of SDA (the term used in this review) is the accumulated energy expended (or heat produced) from the ingestion, digestion, absorption, and assimilation of a meal.
from: Stephen M. Secor: Specific dynamic action: a review of the postprandial metabolic response.
J Comp Physiol B. 2009 Jan;179(1):1-56. doi: 10.1007/s00360-008-0283-7. (full-text)