What type of protein contains all eight essential amino acids?

Proteins are made up of amino acids, which are the building blocks of our body's cells and tissues. Among the 20 different amino acids, there are nine that are considered essential, meaning that the body cannot synthesize them and they must be obtained through the diet. A complete protein is one that contains all eight of these essential amino acids in sufficient quantities to meet the body's needs.

Animal-based proteins, such as those found in meat, dairy, and eggs, are examples of complete proteins, as they provide the full spectrum of essential amino acids. Some plant-based proteins, such as quinoa and soy, also qualify as complete proteins, although many plant proteins are deemed incomplete because they lack one or more essential amino acids or do not contain them in adequate amounts.

In this context, the distinction between complete and incomplete proteins is crucial, as only complete proteins provide the necessary components for maintaining muscle, repairing tissues, and supporting metabolic functions. Therefore, the correct choice emphasizes the importance of including sources of complete proteins in dietary planning, especially for individuals with higher protein requirements, such as athletes or those recovering from illness.