[lemontea88]

What is First Aid trying to say by

"Fasting Day 3 : Muscle protein loss is maintained by hepatic formation of ketone bodies, supplying the brain and heart"

What do they mean by the hepatic formation of ketone bodies maintains the muscle protein loss?

 

[rasheed]

ketones are sythesized from Acetyl Co A which can come from Fatty Acid oxidation. Therefore, when you generate ketones you are burning fat.
If it was without this then you have to break down muscles to get glucogenic amino acids which are then incorporated in hepatic gluconeogenesis to make glucose that's needed as energy fuel for the brain and heart.

This thread may be also useful
http://www.usmle-forums.com/usmle-step-1-forum/810-sources-energy-during-exercise.html

 

[lemontea88]

Oh I see. Cause to me that sentence sounded like our liver is making ketone bodies so that the muscle protein loss can continue on, which sounds quite absurd. Haha. Thanks.