Food intake control and body weight regulation by dietary protein

Abstract

Summary The protein requirement is generally defined as the amount necessary to maintain the body's protein pool. However, under free choice conditions, animal models often ingest more protein than required for nitrogen balance (10%–15%). This behavior possibly reflects the search for a high protein-to-carbohydrate ratio (0.6–0.8), inducing metabolic benefits. This indicates that in addition to protein homeostasis, dietary proteins are also involved in energy homeostasis. The mechanisms controlling protein and energy intake are partly independent and in specific conditions, there may be a conflict between the two. Protein density in the human diet has decreased ∼2% since the 1970s and, according to the protein leverage hypothesis, this decrease may be responsible for the increase in energy intake and prevalence of obesity observed today.