Function in foods: Nutritional value:

Proteins are the important source of amino acids and building blocks for major functional and structural components of cells. Out of 20 amino acids, 9 are called essential amino acids because the human body cannot synthesise them from other compounds. These 9 must be obtained from proteins in food. The quality of a protein depends on the amounts of essential amino acids it provides. Animal proteins, such as eggs, milk, meat and fish, are considered high-quality proteins because they provide sufficient amounts of the essential amino acids. Plant proteins, such as in grain and nuts, are lower-quality proteins because they lack one or more of the essential amino acids.

Furthermore, proteins are an important source of energy. Proteins generally contribute about 10-15% to energy intake. The major proportion of the world proteins intake is derived from plant origin proteins such as cereals, legumes and oilseed. The most important animal proteins sources are meat, eggs and milk.

Title of page

* Amino acids that can be produced by the body, but higher amounts than can be produced may be necessary during times of increased physical or emotional stress, illness or imbalance.

** Histidine is an essential amino acids only in children, not in adults.

Now you will learn more about the function of proteins.