Calories from proteins refer to the energy provided by protein-rich foods. Each gram of protein contains approximately 4 calories. Proteins are essential macromolecules made up of amino acids, which play a crucial role in building and repairing tissues, producing enzymes, and supporting immune function. When you consume protein, your body breaks it down into amino acids, which can be used for energy or to create new proteins. Foods high in protein include meat, fish, eggs, dairy, and legumes. Balancing protein intake with carbohydrates and fats is important for overall health and energy levels.