An amino acid is considered a group of more important molecules when they are part of proteins.
An essential amino acid or indispensable amino acid is an amino acid that the body can not absorb, so it must be ingested in the daily diet. The nine amino acids that humans do not synthesize: are phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidine.
The six amino acids (cysteine, arginine, glycine, glutamine, proline, and tyrosine) are essential in the human diet. Their synthesis can be limited in special pathophysiological conditions, such as prematurity in the baby or individuals at risk of severe catabolism.
Also, five amino acids are essential in humans, which means they can be synthesized in the body: alanine, aspartic acid, asparagine, glutamic acid, and serine.
What should be the minimum daily intake of amino acids?
Estimating the daily demand for the essential amino acids is difficult to know; These figures have been subject to considerable revision in the last 20 years.
The recommended daily intakes for three-year-old children are 10% to 20% higher than the adult levels and for children up to 150% higher in the first year of life. Cysteine (or amino acids that contain sulfur), tyrosine (or aromatic amino acids), and arginine are always required in growing babies and children.
Composition of amino acids in protein sources.
Several attempts have been made to justify the quality of various proteins, including biological value, net protein utilization, protein efficiency rate, amino acid count protein corrected for digestibility, and the complete protein concept.
These concepts are essential in the livestock industry because the relative lack of one or more essential amino acids in animal feed would negatively affect animal growth.
Although proteins from plant sources have low protein concentrations in mass compared to an egg or milk protein, they are nonetheless “complete” because they contain at most minor amounts of all the amino acids essential in people’s nutrition.
Eating various plant foods can provide a protein of high biological value. Inadequate amounts, certain natural combinations of foods, such as corn and beans, soybeans and rice, or red beans and rice, contain essential amino acids necessary for humans.
In addition, certain types of algae and marine phytoplankton predate the division between animal and plant life on the planet; they have as much chlorophyll as plants do and all the essential amino acids, just like proteins of animal origin.