Editing Adenosine triphosphate (section)

====Ketosis====
{{Main|Ketone bodies}}

Ketone bodies can be used as fuels, yielding 22 ATP and 2 [[Guanosine triphosphate|GTP]] molecules per acetoacetate molecule when oxidized in the mitochondria. Ketone bodies are transported from the [[liver]] to other tissues, where [[acetoacetate]] and [[beta-Hydroxybutyric acid|''beta''-hydroxybutyrate]] can be reconverted to acetyl-CoA to produce reducing equivalents (NADH and FADH<sub>2</sub>), via the citric acid cycle. Ketone bodies cannot be used as fuel by the liver, because the liver lacks the enzyme β-ketoacyl-CoA transferase, also called [[thiolase]]. [[Acetoacetate]] in low concentrations is taken up by the liver and undergoes detoxification through the methylglyoxal pathway which ends with lactate. Acetoacetate in high concentrations is absorbed by cells other than those in the liver and enters a different pathway via [[1,2-propanediol]].  Though the pathway follows a different series of steps requiring ATP, 1,2-propanediol can be turned into pyruvate.<ref name="Environmental Protection Agency; TOXICOLOGICAL REVIEW OF ACETONE (CAS No. 67-64-1)">{{Cite web| url=http://www.epa.gov/iris/toxreviews/0128tr.pdf| title=Integrated Risk Information System| date=2013-03-15| access-date=2019-02-01| archive-url=https://web.archive.org/web/20150924074331/http://www.epa.gov/iris/toxreviews/0128tr.pdf| archive-date=2015-09-24| url-status=live}}</ref>