Sure, the point I'm trying to make is that it's easier to cut calories by improving nutrition. I think we eat more calories than we consume when those calories aren't delivering the nutrients we require.

Just refusing to eat more than X amount of calories is an approach that fails for a lot of people. Relying on so-called will power fails for a lot of people.

I think this is a useful distinction to make and doesn't actually contradict the idea that "You get fat from eating too many calories, more than you are burning." Instead it helps answer the question for some people concerning "Yes, but why do you keep stuffing your face when you are so unhappy with the results?"

Laws of thermodynamics are not helpful in this context. Simplest example is: in the absence of glucose/glycogen, our body converts fat to ketones for energy and/or protein to glucose. But unused glucose gets converted to fat and stored, whereas unused ketones get peex out - there is no process to store them again.

Unless you check ketones, a body in ketosis used to HIIT will seem to defy cico balance. And many times even when not in ketosis.

Popular thermodynamics (Carb=Protein=4, Fat=9, etc) is useful as a first order approximation but requires so many wrong assumptions that it cannot be assumed to hold in any particular case.

So, you are essentially saying that regardless of degree caloric surplus, if one is in a state of ketosis they will perpetually loose fat?

It sounds to me like should that be the case (which, sorry I'm rather dubious about), a particular portion of energy conversion is not yet understood rather than the first law of thermodynamics being violated.

I don't claim to be an expert in this area however, so I'll be willing to read any scientific papers you may have to hand on the subject (and while this may come across as sarcastic - it's just my inability to express what I am saying adequately via typing - I'm a true believer that every day is a school day)

Not at all, and I did not say anything of the sort.

What I said was: circulating glucose either gets used or get stored as fat. Which means that counting glucose calories for thermodynamic calculations would actually make some sense (but see below).

Circulating fat get stored as fat, or converted to ketones for use. The difference is, unused ketones get peed whereas unused glucose gets stored.

Ketosis means fat gets converted to ketones for use - but only as much as the body means necessary for activity as that point. If your fat intake exceeds your use, you will likely gain fat.

Thermodynamics is of course never violated. But the “calories in - calories out” statement is not that useful with regard to body weight.

If you drink petrol, you will not gain wait (not be able to use it for energy - you’ll just excrete it) despite being more energy dense than fat (fat is 9kcal/gr, petrol is 12kcal/g). Similarly, plain paper (and indeed the wood it is made of) is a carbohydrate at 4kcal/gr, and yet you won’t derive any energy from it and again excrete it. Does that violate any law of thermodynamics?

No. What it does show is that the assumption that our metabolism is a perfect combustion machine (Which is at the base of the CICO weight theory) is wrong.

The conversion efficiency of different food is measured (and documented) as “Atwater factors”, the value of which was first measured over 100 years ago and assumed constant, but turned out in recent studies to vary among people and and even for same person in different times by 50% or so.

Similarly, for the same physical activity, same person may have a difference of 50%in energy expenditure (e.g. depending on how high feet are lifted while running)

Thermodynamics is not violated, but if you try to reason using it with the appropriate error bars, it turns out that you can’t say much. Statistically, the average is close enough to work for most people, most of the time, but that “most” is 70% or so.

With respect to ketosis - ketones are “use it or lose it” like heat. Once the body converts fat to ketones (a process which is NOT immediate), they are either used or peed out.

If your activity level is close to constant (as most sedantry people are), the body is very good at having very tight control on levels produced, little are wasted and you are close to what you consider “thermodynamic equilibrium” even though it’s not. If you are used to large varying activities, the body will produce more ketones just in case and pee them out if unused - thus you will only consider it “thermodynamic equilibrium” if you consider pee energy content as well.

I’m an electrical engineer, not a biochemist. But I did try to understand nutrition “science” and realized it is at most cargo cult pseudo science.

I don’t have a list of handy references, but at the very least google Richard Feinman’s famous “a calorie is not a calorie” (it’s not the physicist - and note the spelling of the name is different)

However, back in the real world, where caloric and macronutrient labeling is off by up to 20% and NEAT is highly variable, you're pretty much going to have to either eat less or move more if you want to lose weight - some strategies of doing so may be more efficient than others.

For sure. But I lost weight, a lot of it, by moving more or less the same and eating a lot more "caloric content" (switching from mostly carbs to mostly fat), which many people consider "violating thermodynamics", which is nonsense.

If you don't change the ratios of your macros, and you don't make your expenditure vary much throughout the day, then -- yes, eat less, or move more.