A glucogenic amino acid is an amino acid that can be converted into glucose through gluconeogenesis. This is in contrast to the ketogenic amino acids, which are converted into ketone bodies.
The production of glucose from glucogenic amino acids involves these amino acids being converted to alpha keto acids and then to glucose, with both processes occurring in the liver. This mechanism predominates during catabolysis, rising as fasting and starvation increase in severity.
In humans, the glucogenic amino acids are:
Alanine
Arginine
Asparagine
Aspartic
Cysteine
Glutamic
Glutamine
Glycine
Histidine
Methionine
Proline
Serine
Valine
Amino acids that are both glucogenic and ketogenic (mnemonic “PITTT”):
Isoleucine
Phenylalanine
Threonine
Tryptophan
Tyrosine
Only leucine and lysine are not glucogenic (they are only ketogenic).

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