Which food source is most likely to contain complete proteins?

Meat and dairy products are recognized as the primary sources of complete proteins, which are proteins that contain all nine essential amino acids necessary for human health. These essential amino acids cannot be synthesized by the body and must be obtained through diet. Animal-based foods like meat and dairy are typically rich in these amino acids in adequate proportions, making them ideal for meeting the protein needs of the body.

In contrast, plant-based foods, like pasta, fruits, vegetables, and grains, often contain one or more amino acids in lower amounts, categorizing them as incomplete proteins. While some plant sources combine to provide a complete amino acid profile (for example, beans with rice), they do not independently provide all essential amino acids in sufficient quantities as animal products do. Thus, meat and dairy products stand out as the most reliable sources of complete proteins in the diet.