Effect of fat loss on energy consumption

I could get a pretty accurate estimate of my Total Daily Energy Expenditure because I knew my body fat % before I started losing fat. My question is, how much can I expect that to change after losing fat? I get practically no exercise (just sitting all day). My own assumption is that the change should be negligible because I’m not losing anything that uses a lot of energy for upkeep.

Hey Dia!
I’m not sure I follow your question entirely. If you’ve lost body fat and have a sedentary lifestyle, your daily calorie requirements will increase slightly, but this will depend on a variety of factors, including your age, physiology, and habits. The amount of calories you’ll need to maintain your weight will differ depending on how much fat you’ve reduced.

You link to this calculator in your fat loss guide: https://tdeecalculator.net/. Basically what I’m asking is, should I assume all the weight I lose is fat for the purpose of recalculating my TDEE (assuming my lifestyle doesn’t change). I noticed that when I did that, my TDEE didn’t change even as I lost weight.

If you live a sedentary lifestyle and reduce your calorie consumption, you may be burning fat, but this relies on a variety of factors unique to you. If you lose weight while also lowering your body fat percentage, the number of calories you consume may remain constant, which is ok. In this instance, the best course of action is to take another body fat measurement to be sure how your body is reacting to the weight loss.