What is the primary source of dietary protein?

The primary source of dietary protein includes animal products and legumes because they provide a complete amino acid profile that is essential for various bodily functions. Animal products, such as meat, dairy, and eggs, are considered complete proteins, containing all the essential amino acids that the human body cannot synthesize. Legumes, such as beans, lentils, and peas, while generally considered incomplete proteins on their own, can still provide significant protein content and are often combined with grains to create a complete protein profile.

Cereals and grains, while they do have some protein, typically lack one or more essential amino acids, making them less ideal as the primary source. Fruits and vegetables also contain very low amounts of protein relative to the other groups and should not be relied upon for protein needs. Processed snacks often lack nutritional value and may not provide a significant or quality source of protein. Thus, animal products and legumes stand out as the most reliable and nutrient-dense sources of dietary protein.