In keeping with reconciling that this is the Show Me the Science category…
The problem with CiCo is that they are not independent variables. CaloriesOut is a function of CaloriesIn (in the mathematical sense), and CaloriesIn is a function of CaloriesOut - at least in a “free living human”. That is, someone not deliberately trying to restrict the CaloriesIn. For those of us who have taken control theory in engineering school, this is a feedback loop; a self-regulating system. That was evident to me about 30 years ago.
There is nothing you can do your output that doesn’t end up affecting your input, and nothing you can do to your input that doesn’t end up affecting your output. These are things that are beyond our control.
Jason Fung, as I’m sure you know, likes to say that CiCo has a perfect track record of not ever working in an experiment. I think we’ve all experienced that, or at least most of us have.
In fact, I wonder if the reason many of have had problems like this with stalling or gaining back on keto is that we’re very experienced dieters and our body has learned to adapt to whatever we throw at it. I have no proof of that in any real sense.
I like Gary Taubes’ view that it’s not that calories don’t matter, it’s that saying your weight change corresponds to more calories (in or out) isn’t telling you anything. Gary’s view is that we don’t gain weight because we ate more calories, we ate more calories because we were gaining weight.
I recall reading about some researchers looking to study something related to weight loss diets and who needed a population of overweight college students who had never dieted. The gave up because they never found a population who had never dieted.
I hear anecdotal reports of people stalled at some weight who suddenly broke the stall and spontaneously lost weight. Nina Teicholz spoke about that in the last podcast. But that’s not an unbiased sample; people are more likely to tell you they spontaneously lost weight by “KCKO”, but don’t seem to say they spontaneously gained weight.