Protein turnover and thermogenesis in response to high-protein and high-carbohydrate feeding in men.
The rates of energy expenditure and wholebody protein turnover were determined during a 9-h period in a group of seven men while they received hourly isocaloric meals of high-protein (HP) or high-carbohydrate (HC) content. Their responses to feeding were compared with those to a short period of fasting (15-24 h). The 9-h thermic response to the repeated feeding of HP meals was found to be greater than that to the HC meals (9.6 +/- 0.6% vs 5.7 +/- 0.4% of the energy intake, respectively, means +/- SEM, p less than 0.01). The rate of whole-body nitrogen turnover over 9 h increased from 17.6 +/- 2.2 g on the fasting day to 27.4 +/- 1.4 g during HC feeding (NS) and there was a further increase to 58.2 +/- 5.3 g resulting from HP feeding (p less than 0.001). By using theoretical estimates (based upon ATP requirements) of the metabolic cost of protein synthesis, 36 +/- 9% of the thermic response to HC feeding and 68 +/- 3% of the response to HP feeding could be accounted for by the increases in protein synthesis compared with the fasting state.
Institute of Physiology, University of Lausanne, Switzerland.
S M
SM
Robinson
C
C
Jaccard
C
C
Persaud
A A
AA
Jackson
E
E
Jequier
Y
Y
Schutz
D000328:Adult; D001481:Basal Metabolism; D001786:Blood Glucose / Q000032:analysis; D001824:Body Constitution; D001833:Body Temperature Regulation / Q000187:drug effects*; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000494:pharmacology*; D004044:Dietary Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D004435:Eating / Q000502:physiology; D004734:Energy Metabolism; D005215:Fasting; D005227:Fatty Acids / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D010101:Oxygen Consumption; D011506:Proteins / Q000378:metabolism*
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D005227:Fatty Acids; D007328:Insulin; D011506:Proteins; D009584:Nitrogen