- Animal sources
- Plant sources
Therefore, the proteins in our diet come either from foods of animal origin or plant origin.
Animal sources are complete proteins, such as meat,egg, fish, poultry.Milk is also a valuable source of protein although it does not contain a large quantity of protein but the quality is excellent.
Gelatin, a derived protein is an exception since it lacks three essential amino acids and , hence, it is a poor source.
Good sources of plant proteins are legumes,pulses,nuts and oilseeds. But the quality of these proteins is poorer than that of flesh foods. All vegetables and fruits are a poor source of protein.