Ketogenic amino acid

A ketogenic amino acid is an amino acid that can be degraded directly into acetyl-CoA, which is the precursor of ketone bodies. This is in contrast to the glucogenic amino acids, which are converted into glucose. Ketogenic amino acids are unable to be converted to glucose as both carbon atoms in the ketone body are ultimately degraded to carbon dioxide in the citric acid cycle.

In humans, two amino acids are exclusively ketogenic:

(remembered as all the "L" amino acids)

In humans, five amino acids are both ketogenic and glucogenic:

(remembered by the useful mnemonic "PITTT" or "FITTT", and includes all the "T" amino acids)

In humans, the remaining thirteen amino acids are exclusively glucogenic (i.e. are not ketogenic).

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