[12] Alanine is a nonessential amino acid, meaning it can be manufactured by the human body, and does not need to be obtained through the diet.

[6]: 721  Because transamination reactions are readily reversible and pyruvate is present in all cells, alanine can be easily formed and thus has close links to metabolic pathways such as glycolysis, gluconeogenesis, and the citric acid cycle.

[14] Racemic alanine can be prepared by the condensation of acetaldehyde with ammonium chloride in the presence of sodium cyanide by the Strecker reaction,[15] or by the ammonolysis of 2-bromopropanoic acid.

[6]: 721 Alanine is one of the twenty canonical α-amino acids used as building blocks (monomers) for the ribosome-mediated biosynthesis of proteins.

Alanine is believed to be one of the earliest amino acids to be included in the genetic code standard repertoire.

[21] This hypothesis explains the evolutionary choice of amino acids in the repertoire of the genetic code from a chemical point of view.

In this model the selection of monomers (i.e. amino acids) for ribosomal protein synthesis is rather limited to those alanine derivatives that are suitable for building α-helix or β-sheet secondary structural elements.

Dominant secondary structures in life as we know it are α-helices and β-sheets and most canonical amino acids can be regarded as chemical derivatives of alanine.

Therefore, most canonical amino acids in proteins can be exchanged with alanine by point mutations while the secondary structure remains intact.

In addition, classical X-ray crystallography often employs the polyalanine-backbone model[22] to determine three-dimensional structures of proteins using molecular replacement—a model-based phasing method.

The alanine aminotransferase reaction takes place in reverse in the liver, where the regenerated pyruvate is used in gluconeogenesis, forming glucose which returns to the muscles through the circulation system.