| Sometimes - but they ARE metabolized through the same pathway. Essentially: Glucose ->[0] pyruvate ->[1] acetyl-coa -> TCA cycle
vs Fatty acids ->[2] acetyl-coa -> TCA cycle
The TCA is cycle is the actual main energy generating step.Other times fat absolutely is converted to sugar. It all depends on the metabolic needs of the body and one building blocks are available, and what protein "workers" are able to use the ones that are available. For example, fatty acid synthase converts acetyl coa back to a fatty acid [3]. [0] Glycolysis: http://en.wikipedia.org/wiki/Glycolysis [1] pyruvate dehydrogenase: http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase [2] beta oxidation: http://en.wikipedia.org/wiki/Beta_oxidation [3]: http://en.wikipedia.org/wiki/Fatty_acid_synthase |