Adipose tissue can't be just fat. If it was just fat it would be mostly liquid and slosh around. So I guess it must also have lower caloric density than pure fat, i.e. you lose more weight for a given calorie deficit than would be expected if you lost fat only.

Is this true and if yes, what are the values for both abdominal/visceral fat and for subcutaneous belly fat?

I'm asking because I've been losing weight faster than anticipated and wonder why. If the weight lost would translate to calories with the factor 7000kcal/kg, then I would have a daily deficit of 2000kcal which is not very believable considering I feel fine and am not trying very hard.

Possibly irrelevant stats just in case: 11 days, 3.3kg down from 75.1 originally, eating around 1000kcal/day (maybe more, not keeping track exactly), 1.72m tall, 7 proper work outs in that time of which 6 were one hour intense and one was 4 hours not that intense. The amount of sports is pretty normal for me, but I used to eat much more. The fat that I think I'm losing is subcutaneous belly fat and abdominal fat (see Wikipedia on adipose tissue types), I have a typical male body shape, i.e. fat is in belly and nowhere else.

  • Are you a man, woman? Most men maintain weight around 2500 calories per day, if you’re only eating 1000 then that’s potentially 1500 calories by itself. Working out will only further this massive deficit. Also, I’m not sure that understanding the composition of body fat is even relevant to what you are actually trying to figure out. Especially since you are likely losing muscle mass as well. Not to mention how you don’t seem to be considering glycogen and water and food as part of the weight you are losing. Feb 29, 2020 at 14:36
  • @JustSnilloc Well I'm not sure how helpful and/or relevant it is, but I'm a curious person. I'm pretty sure my performance is at least staying level if not improving, so I doubt I'm losing muscle mass. Although I don't recently do much sports where performance is easily measured, I just notice I can more and more easily keep up with the others in the group and recover ok afterwards.
    – Nobody
    Feb 29, 2020 at 15:03
  • @JustSnilloc So for glycogen I would have lost about 2000kcal/500g once at the beginning when I started to have a deficit, if we assume it's now constantly depleted, less if we assume it's partially filled up again from body fat/food. Muscle is of course possible but I haven't noticed yet and would stop once I noticed. I don't understand the part about food and water, I drink lots so I don't know why I would have less stored water, and in daily life it should be a wash and I weight myself on an empty stomach anyway... if you want to write a more general answer than what I asked, feel free. :)
    – Nobody
    Feb 29, 2020 at 16:57
  • @Nobody -- the 7000 kcal/kg (3500 kcal/lb) weight loss factor is a myth, or rather, its been debunked.
    – C. Lange
    Mar 2, 2020 at 19:56
  • I'm voting to close this question as off-topic because this is probably better suited for biology, but would need the personal details edited out and the main question about the caloric density clarified some.
    – JohnP
    Mar 2, 2020 at 20:46


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