Interaction of dietary protein and energy balance

Nutrition plays a key role in the prevention of cardiovascular disease, acting in part, on the prevention and treatment of obesity. Here the role of dietary protein in energy balance and weight regulation with consequent implications for the prevention and management of cardiovascular diseases is described. An energy-restricted high-protein diet has been shown to achieve body weight loss and subsequent weight maintenance by reducing energy intake without changing appetite, and maintaining energy expenditure by preserving FFM. Mechanisms behind protein-induced appetite control and energy expenditure are direct and indirect effects of elevated plasma amino acid and anorexigenic hormone concentrations, increased diet-induced thermogenesis (DIT), and a ketogenic state. Mechanisms behind protein-induced energy expenditure and preservation of fat-free mass are metabolic inefficiency, due to processing, protein turn-over, and possibly gluconeogenesis. In neutral energy balance, a protein diet may prevent a positive energy balance due to the higher energy expenditure. With respect to reward homeostasis, protein-induced food reward is limited, and may affect compliance to a protein-modified diet. When applied within a range of 0.66-1.66 g/kgBW/d, protein consumption has not been associated with increased health risks. Even in the elderly, beneficial health effects of higher-protein intake might outweigh possible adverse effects. In conclusion, higher-protein diets may reduce cardiovascular disease risk by decreasing the susceptibility for the development of obesity.