Name two dietary sources of complete proteins.

Complete proteins are those that contain all nine essential amino acids that the human body cannot produce on its own. Animal products and soy are excellent sources of complete proteins because they provide the full range of these essential amino acids necessary for maintaining health and supporting bodily functions.

Animal products, including meat, fish, poultry, eggs, and dairy, are well-known for being complete protein sources because they naturally contain all the essential amino acids in sufficient quantities. Similarly, soy is unique among plant-based foods as it is one of the few vegetarian sources that also contains all nine essential amino acids, making it an excellent alternative for those who do not consume animal products.

Other options include various food groups that may offer proteins but not all essential amino acids in adequate proportions. While fruits and vegetables, lentils, and nuts and seeds are valuable components of a balanced diet, they do not qualify as complete proteins. For instance, most plant-based proteins are classified as incomplete because they lack one or more essential amino acids. Therefore, the combination of animal products and soy stands out as the definitive source of complete proteins.