About Protein
Protein is built from amino acids and is constantly being broken down and rebuilt throughout the body. Its jobs include muscle structure, enzymes, transport proteins, receptors, hormones, antibodies, and tissue repair.
Amino Acids
Proteins are chains made from amino acids.
Learn MoreProtein Jobs
Protein does far more than build muscle.
Learn MoreAnimal Sources
Meat, poultry, fish, eggs, dairy, and seafood provide protein.
Learn MorePlant Sources
Beans, lentils, peas, soy, nuts, seeds, and grains also provide protein.
Learn MoreGrowth and Repair
Protein supports growth and tissue maintenance.
Learn MoreDigestion
Digestive enzymes break proteins into peptides and amino acids.
Learn MoreNeeds
Protein needs vary with body size, age, growth, activity, and health.
Learn MoreVariety
Different protein foods bring different nutrients.
Learn MoreAmino Acids
The body uses about twenty standard amino acids. Some can be made internally, while essential amino acids must come from food.
Protein Jobs
Enzymes speed reactions, antibodies support immunity, transport proteins move molecules, and structural proteins help form skin, hair, connective tissue, and cells.
Animal Sources
These foods also differ in fat, vitamins, minerals, sodium, and preparation method, so variety within the group matters.
Plant Sources
A varied plant-based pattern across the day can supply all essential amino acids without needing to pair exact foods at every meal.
Growth and Repair
Children and teenagers need protein as part of normal growth, while everyone needs it for replacing cells and repairing tissues.
Digestion
Protein digestion begins in the stomach and continues in the small intestine. Absorbed amino acids enter the bloodstream and can be used throughout the body.
Needs
More is not automatically better. Overall energy, carbohydrates, fats, vitamins, minerals, sleep, and activity also matter.
Variety
Fish can supply omega-3 fats, beans provide fiber, dairy can provide calcium, and nuts and seeds offer unsaturated fats and minerals.