How many kilocalories do proteins provide per gram?

Proteins provide approximately 4 kilocalories per gram. This is a fundamental principle in nutrition, as macronutrients are categorized based on the energy they yield upon digestion and metabolism. Proteins are composed of amino acids, which the body uses for various vital functions, including building and repairing tissues, producing enzymes and hormones, and supporting immune function.

Each macronutrient has a specific caloric value: carbohydrates also yield about 4 kilocalories per gram, while fats provide about 9 kilocalories per gram. This knowledge is crucial for individuals focusing on dietary planning, energy balance, and overall nutritional science. Therefore, the understanding that proteins contribute 4 kilocalories per gram helps to inform dietary choices and manage energy intake effectively.