Protein is made of building blocks called amino acids. Although the human body can make some of these amino acids, nine of them (the essential amino acids) must be obtained from food. Soy foods and animal sources of protein (milk, eggs, meat, poultry, fish, and seafood) contain all the essential amino acids in the amounts our bodies need.
Most plant foods contain some of the essential amino acids in varying amounts. Beans have some amino acids, and grains have other amino acids. Eating these different types of food throughout the day will provide your body with adequate protein. They complement each other to form a whole protein.
Foods that contain protein
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