define closed… for instance, the laws of energy conservation apply to the entire universe.
of course - if you really want to talk about the science behind it, then let me point out that 96% of the physical universe is not covered by our “immutable laws of nature”. Its all dark matter and dark energy - which is science speak for “we have no fricking idea what this is all about - so lets pretend that what we see is the whole truth and no one will be the wiser”
well - 
in the end it kinda is, right?
CICO is true, its just that both sides are moving targets, with CO adjusting in the short term and the long term to CI. Food in the GI tract is the first buffer, then blood glucose is the next buffer (very tiny - 1 tsp total), then glycogen stores, then fat stores.
Ooohhhh… so how about maybe CICO has something to do with quantum entanglement? The fat on my thighs has become part of the horseshoe nebula. 
Fuck that. The fat on my belly WAS a distant sun going Supernova. its now slowly becoming a red dwarf! 
I could be wrong but isn’t the issue not that CICO doesn’t exist conceptually (and very complex-ly - a word?) but that it is largely worthless because neither side can be calculated accurately for many of the reasons mentioned here nor can we predict their reactions to different contexts/situations. When people manage calories and get a specific result it isn’t necessarily because they’ve cracked energy balance via CICO but that their system has done various things to achieve the result e.g. used, wasted, stored, extracted from storage, etc., energy substrates?
Attributing specific results to particular estimated calorie levels seems rather more luck than judgement 
Fruits are not keto unless they are berries and only in small amounts. I have had to avoid alcohol as well. An occasional glass of dry wine is supposed to be ok …or an oz. Of hard liquor. But my goal is weight loss and better health so I avoid.
Perhaps the first thing is for everyone to calm down. I’m sorry, Karen, that your first post got misinterpreted a bit, but a lot of people come to these forums without having read much, and it is a shame, because they panic needlessly. And we sometimes get tired posting the same ideas over and over.
But even after reading your post about having done the research, I can’t shake the feeling, when I read your original post over again, that you were saying that you were going to quit because you haven’t seen any progress during your first week. All the stuff I read and watched before going keto made it clear to me that any improvements were going to be long-term ones, and that expecting any results the first week was highly unrealistic. It is also a clearly-articulated part of our collective experience that women have a harder time shedding pounds than men do. Partly this is because the body often takes the opportunity to build up lean tissue, even while it may at the same time be shedding excess fat. This confuses your scale, so we usually tell women to give their scales away and go by what’s happening with their dress size.
You are going to get a lot of advice on these forums, some of it conflicting. Part of the problem is the science is changing, part of it depends on which experts each one of us is listening to ('cause they don’t always agree), and part is that we don’t always understand correctly—or remember correctly!—the things we read and listen to. But if you want to get into nutritional ketosis, the standard advice is the following: keep carbohydrate intake under 20g/day; keep protein moderate (0.8-1.0 g/kilo of lean body mass/day); and eat fat to satiety. The third point is important because if you fail to give your body enough calories, it will go into famine mode and lower your metabolic rate and close off any less-critical processes it can, in order to keep expenditure in line with intake. This also means that it hangs onto its store of fat. But in the absence of insulin (the point of keeping carbs low) and given enough calories, the body will speed up the metabolism and burn off its excess fat store. And the only way to give your body the calories it needs is by eating fat till your body says “enough!”
The process of fat-adaptation can take several weeks, but satiety signalling should sort itself out sooner than that. But try to give keto at least three months before giving up. This way of eating may very well not be for you, but you won’t know for sure unless you give it a fair try.
I prefer Gary Taubes’ way of putting it: ΔE = CI - CO actually says nothing about the direction of causality. We assume that ΔE increases because CI does and CO does not, when perhaps it’s really that CI has increased and CO decreased because of ΔE.
After all, no one claims that growing children are growing taller because they suddenly decided to start eating more—we all understand that they inhale food because their growth spurt is demanding that they increase their food intake. In the same way, the German nutritionists reasoned, back between the wars, perhaps people are eating more and moving less precisely because their fat store is growing, not the other way around, as we commonly assume. The known science of how insulin enforces fat storage certainly gives credence to this hypothesis.
this summaries my youth. from thin and incredible energy to pudgy and distancing myself from physical exertion. My older siblings were all thin through high school. Just so happens I was born a bit later, when margarine and refined products were in vogue. Then came the microwave and ‘easy food’.
Thank you for the new information for my perspective!
Glad to help. It is also highly likely that some of us are more vulnerable to the ill effects of carbs than others are. Age has something to do with it too, I believe. At any rate, I was able to eat any kind of food in outrageous quantities until my late twenties or early thirties without gaining a single pound. Boy did that change! Unfortunately, my appetite did not.
At least now it all makes sense.