and I wouldn't say always: "Pure fat has a very high energy content, or about 9 calories per gram. This amounts to about 4,100 calories per pound of pure fat.

and I wouldn't say always: "Pure fat has a very high energy content, or about 9 calories per gram. This amounts to about 4,100 calories per pound of pure fat. However, body fat is not just pure fat. Body fat consists of fat cells, called adipocytes, which also contain some fluids and proteins in addition to fat. Therefore, the calorie content of body fat is going to be a bit less than the calorie content of pure fat." [1] https://www.healthline.com/nutrition/calories-in-a-pound-of-fat#TOC_TITLE_HDR_2 https://www.healthline.com/nutrition/calories-in-a-pound-of-...