Does you actually believe in the virtue theory of metabolism, or did you believe in the conservation of energy between ATP synthesized thorough the breakdown of food nutrients being used to synthesize lipids?

There are additional confounding factors, including genetics, heredity separately from genetics (many organelles are not coded in DNA), and environmental factor which cause hormone fluctuations. Seth Roberts' studies as linked show variations in appetite which cause variations in body fat, and provide a clear theory on a specific mechanism by which appetite can be intentionally altered.