Protein catabolism is the process by which proteins in the body are broken down into smaller units called amino acids. This occurs primarily in the liver and muscles, where enzymes help to dismantle the protein structure. The amino acids can then be used for various functions, such as energy production, synthesis of new proteins, or conversion into other molecules. During protein catabolism, excess amino acids that are not needed for protein synthesis can be converted into glucose or fatty acids. This process helps maintain energy balance and provides the body with necessary nutrients when carbohydrates or fats are scarce. Overall, protein catabolism is essential for maintaining metabolic functions and supporting overall health.