Oh, so now it is macros in, calories out? We've already abandoned CICO? Excellent. Let's go further--

Your body doesn't even process macros the same. Some carbohydrate types you'll process in your liver to produce triglycerides and adipose--other carbohydrates you'll turn directly into body heat. Additionally, there is wild variation in your ability to absorb and digest different nutrients inside the same macro category.

So where are we now? Macro sub-type, adjusted for absorption rates in, calories out?

Oh, but it gets worse for your unscientific "fact" of CICO--measuring calories out is meaningless. Two people can have the same height, weight, and physical activity pattern but can have a "calories out" that vary by hundreds of percent.

So let's make it macro sub-type in, calories out for a specific person--except it gets worse for CICO! A person's basal metabolism can vary drastically day to day and week to week. Their "calories out" is some moving target that must constantly be remeasured.

But it gets worse! (Can you believe it?) their "calories out" will actually react to their reducing calories, and reduce their basal metabolism.

Hold any kind of magnifying glass to CICO and it falls apart. Oh, we didn't even talk about how inaccurate caloric readings of food is in the first place