Feeding frequency and protein metabolism

Abstract

Normal young adult male rats were allowed to eat a diet of a specified protein content ad libitum, or were pair-force-fed the same diet twice a day. At the end of 14 days of controlled feeding, the animals were killed and analyzed for total body lipids. These analyses showed that the fat content of the force-fed animals, relative to those that ate ad libitum, became progressively greater as the dietary protein was increased in quantity from 0 to 67% of the diet. Furthermore, it was observed that force-fed animals excreted about 37% more urea nitrogen over a 7-day period than pair-fed animals eating ad libitum. Abruptly reversing the feeding habits of the rats immediately reversed the relative amounts of urinary nitrogen they excreted. The results of both types of experiments suggest that the intermediary metabolism of protein is related to feeding frequency (or load of absorbed nutrients to be metabolized per unit time). With fewer feedings but with total 24-hr intake constant, less dietary protein appears to participate in protein anabolic reactions since larger amounts of nitrogen are lost in the urine.

Effect of feeding frequency on food intake and growth of Arctic charr, Salvelinus alpinus L.

“…In rats, changes in meal frequency have been suggested as the cause of alterations in body composition, leading to increased fat accumulation (Cohn & Joseph, 1963;Han, 1973;McCracken, 1975). Restricted feeding may lead to improvements in growth efficiency (Leveille, 1970).…”

Adaptation to the pattern of food intake: some mechanisms and consequences

“…The deaminated remnants of amino acids can then be used as a source of energy or as material for synthesis of non-nitrogenous body constituents, including fat. This concept is supported by Cohn's findings that forced feeding leads to an increase of body fat even on high-protein diets which contain as much as 67% protein (Cohn et al 1963).…”

“…Cohn, Joseph, Bell & Oler (1963) and Cohn, Joseph, Bell & Frigerio (1964) found that rats force-fed excrete more urea nitrogen and also have a raised activity of arginine synthetase in the liver. It may be postulated that as a response to periodic loads of a substrate mixture an increased protein turnover and an increased shunting of amino groups in the Krebs urea cycle take place.…”

Effect of Feeding-Fasting Interval on Finishing Pigs: Weight Gain, Feed Utilization and Physical and Chemical Carcass Measurements

“…HE frequency of feeding of laboratory animals has marked effects on metabolism of nutrients (Cohn andJoseph, 1959, 1960a;Cohn et al, 1963;Hanson, 1965, 1966;Tepperman and Tepperman, 1958). This is manifested in increased body fat in "meal-fed" rats as compared to "nibblers."…”