Of the more than twenty amino acids contained in protein, eight are essential amino acids for adults and nine are essential amino acids for infants. Essential amino acids are those amino acids that cannot be synthesized by the human body or other vertebrates, or are synthesized at a rate that is far from sufficient to meet the needs of the body, and thus must be supplied by dietary protein. The eight essential amino acids for adults include lysine, phenylalanine, methionine, threonine, isoleucine, leucine, fethionine, and tryptophan. In addition to the eight essential amino acids for adults, the essential amino acids for infants include histidine. These essential amino acids are usually consumed through food in daily life and are usually found in high quality proteins. The main food groups rich in high-quality protein are aquatic, livestock meat, eggs, dairy and legumes and their products, specifically tuna, sardines, salmon, shrimp, shellfish, eggs, soybeans, chicken and beef. Excessive consumption or insufficient supply of amino acids can lead to a series of clinical symptoms. For example, threonine is effective in protecting cell membranes and promoting human development, and its deficiency can lead to wasting and even death. Valine has the functions of promoting growth, repairing tissues, regulating blood sugar and providing energy, etc. Deficiency may lead to disorders in the central nervous system of the brain, ataxia and tremors in the limbs. When tryptophan content is abnormal, it may lead to abnormal liver function, tryptophanuria, etc. In addition, abnormal levels of glycine, alanine, arginine, lysine, serine and histidine can also lead to some corresponding abnormal metabolic diseases, so daily attention should be paid to supplementation. If any of the above amino acid deficiency manifestations occur, you should immediately seek medical attention for timely supplementation and treatment.