Alcohol metabolism is pretty complex, though. Your liver can only process so much at once, so you’re not going to extract all the available energy from it if yo

Alcohol metabolism is pretty complex, though. Your liver can only process so much at once, so you’re not going to extract all the available energy from it if you’re drinking quickly/heavily, because the body will start excreting the excess acetic acid as urine. That is, a bottle of wine has ~600 Cal in ethanol alone, but to actually get those calories out of it, you would need to drink it slowly, one glass at a time—you won’t actually get 600 Cal out of it if you drink it in one sitting. Anecdotally: when I used to drink quite heavily a few years ago, I was consuming 500–1000 Cal of ethanol a day, yet still eating a normal ~2000 Cal diet, with ~2 hours a day of moderate physical activity, and losing weight.