[Reflex of food-induced thermogenesis in normal subjects and its changes in patients with obesity].

Dog experiments have established that an initial period of food-induced thermogenesis (FIT) has a reflex nature. This is proved by FIT appearance in sham feeding and disappearance after atropine administration. Various food substances proved capable of evoking this reflex. It was also registered in humans. Oxygen consumption rose within 3-10 minutes after a test meal reaching a 25% maximal increment. However, no or minimal manifestations of the reflex occurred in obese patients. They had to undergo a 30-day weight-reducing treatment to reacquire the lost reflex. Physiological value of FIT as a mechanism stimulating tissue metabolism and preparing food substances assimilation are discussed.