Thermic effect of food after ingested versus tube-delivered meals
Hill, J.O.; DiGirolamo, M.; Heymsfield, S.B.
American Journal of Physiology 248(3 Pt 1): E370-E374
1985
ISSN/ISBN: 0002-9513 PMID: 3919595 Document Number: 254263
In 6 persons, the thermic effect of food (TEF) after ingestion of a test meal was compared with that after delivery of an equivalent test meal directly into the stomach through a nasogastric tube. TEF was estimated after each test meal (i.e., ingested or tube-delivered) until postprandial metabolic rate was not different from fasting metabolic rate (as measured at about the same time of day on a previous day). TEF after the tube-delivered meal was not significantly different in magnitude or duration from TEF after the ingested meal. The 2 types of meals also resulted in similar changes in respiratory quotient. The results suggest that most TEF arises after the food reaches the stomach and that very little TEF is produced by sensory factors or by the mechanical aspects of eating.