What are proteins and where do they come from?
-Proteins are the “building blocks of life” and necessary for good health. Proteins are made of chains of up to 20 different amino acids. During digestion, proteins are broken down into amino acids for the body to use.
-Amino acids are generated by the body or obtained through food. There are eight “essential” amino acids that cannot be made by
adult bodies and must be eaten.
“Complete” proteins contain all the essential amino acids in adequate amounts. Foods with complete proteins include meats and animal
products such as milk, yogurt, cheese, and eggs. Soybean proteins, as in tofu or “soy milk,” are also complete proteins.
“Partially complete” proteins contain all the essential amino acids, but the amount of one or more of those essential amino acids is
inadequate. Most proteins in a plant group are only “partially complete” but can be made “complete” if combined with another protein
― legumes (beans) + grains = “complete” protein (e.g., peanut butter sandwich)
― grains + dairy = “complete” protein (e.g., cereal and milk)
― grains + nuts or seeds = “complete” protein (e.g., granola)
Why are proteins important?
-Provide needed components for gene and cell reproduction.
-Carry out the instructions of the genes in the cells.
-Form a major part of muscle, including the heart.
-Make up tendons and most connective tissues.
-Help make up collagen and cartilage, which determines the shape of the skeleton.
-Direct and control the chemical reactions of life as enzymes.
-Direct and balance body functions as hormones.
-Repair body damage by forming scar tissue.
-Defend against infection as antibodies.