Sometimes - but they ARE metabolized through the same pathway. Essentially: Glucose ->[0] pyruvate ->[1] acetyl-coa -> TCA cycle vs Fatty acids ->[2

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 http://en.wikipedia.org/wiki/Glycolysis [1] pyruvate dehydrogenase: http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase [2] beta oxidation: http://en.wikipedia.org/wiki/Beta_oxidation http://en.wikipedia.org/wiki/Beta_oxidation [3]: http://en.wikipedia.org/wiki/Fatty_acid_synthase http://en.wikipedia.org/wiki/Fatty_acid_synthase