PROTEIN AND AMINO-ACID INTAKE IN CAFETERIA FED OBESE RATS

Food selection pattern and portal blood amino acid profile were examin ed in rats given a cafeteria diet. Compared to standard-diet fed rats, cafeteria-diet fed rats consumed more energy. Increase in energy inta ke was attributable to an increase in fat intake. Protein intake was s lightly higher and carbohydrate intake remained constant and was simil ar to levels consumed by standard-diet fed rats, The cafeteria rats to ok up higher quantities of Phenylalanine+Tyrosine, Arginine, Histidine , Lysine, Leucine, Isoleucine, Valine, Threonine, and Glycine, lower q uantities of Tryptophan and the same quantity of Methionine+Cysteine v s. control rats. Portal concentrations of Serine, Threonine, Tryptopha n and Lysine were significantly higher in cafeteria-diet fed rats than in standard-diet fed rats. This can be interpreted in such a way that , on the whole, the quality of protein ingested by cafeteria and contr ol rats is similar. No statistical differences in the ingestion of ind ividual amino acids were observed between different days of the period of cafeteria diet feeding, thus the idea of a strict control of prote in ingestion irrespective of the obese status is reinforced.