Out of the total amino acids, how many are considered essential?

The number of essential amino acids is considered to be nine. Essential amino acids are those that the body cannot synthesize on its own and therefore must be obtained through diet. These amino acids play critical roles in various bodily functions, including protein synthesis, hormone production, and neurotransmitter regulation.

The essential amino acids include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Understanding that these nine amino acids must be acquired from dietary sources is fundamental for maintaining a balanced and healthy diet, especially for those following specific dietary restrictions or lifestyle choices.

The other choices do not align with the established scientific consensus regarding the number of essential amino acids required by the human body.