How do we gain energy out of fat?

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When glucose is depleted, the body shifts to fat as its primary energy source, which contains 9 calories per gram—more than double that of carbohydrates. The process of converting fat into energy is more complex and time-consuming than glucose metabolism. Fat must first be broken down into fatty acids and glycerol, each of which follows distinct pathways to produce energy. For instance, palmitic acid, a common saturated fat, yields 130 ATP molecules per fat molecule. The oxidation of fats not only provides energy but also generates water, highlighting an often-overlooked aspect of fat metabolism. For further reading, biochemistry textbooks and resources like the National Center for Biotechnology Information offer detailed insights into fatty acid metabolism.
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"When your body runs out of glucose, it turns to fat for energy, which has 9 calories in every gram. This is a little more than double the amount in carbohydrates. Converting fat into energy takes longer than it does to convert glucose into energy, because fat must be first be broken down into its two component parts: fatty acid and glycerol. Each part follows a separate pathway to ultimately become available as energy. One common saturated fat, palmitic acid, makes 130 molecules of ATP for each molecule of fat."

This is all I found about this topic in the internet. Could you please explain it further (how fat is broken down exactly to convert it into energy) or find a source where I can read more about it?
 
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This is a topic that is covered in most Biochemistry textbooks (some of which are freely available online). For example, see:
https://www.ncbi.nlm.nih.gov/books/NBK21173/
https://www.ncbi.nlm.nih.gov/books/NBK22581/
 
Yes, this is an invitation to write several textbook chapters, which we often get - not efficient to do for one student!

That said, a little fact I like that seems often overlooked, is that the oxidation of fats is the source as well as of energy, of water. The camel's hump is fat, not water
 
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