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Re:Why Calorie Counts Are All Wrong by jerf on Monday August 17, 2015 @11:49AM (#10073781)
"At the end of the day, it's always calories in vs calories out.

Scientifically sound food recommendations [1] accept that different types of calories make you feel more or less full."

That's a contradiction. The entire idea of "calories in, calories out" is precisely that there is no difference and all calories are exactly the same. If some make you feel less full than others, then you're invoking the existence of the feedback loop that "calories in, calories out" explicitly denies.

If you, as this article does, point out that many things affect whether a calorie can be absorbed, that is, again, another difference between calories.

If modern science is moving on... and it is, at an inexcusably sluggish pace... it's moving on from "calories in, calories out". There's really no way to salvage it... even if you want to go with "calories digested vs. expended" you've still got a complicated feedback loop even there between the pancreas, insulin, blood stream, various bits of the brain, the metabolic consumers of blood sugar (significant differences here too between muscles vs. organs), etc, and even two people who hypothetically start with the exact same blood sugar levels and digestive system state will rapidly diverge as this feedback loop does different things between them. "Calories in, calories out" is only true as a limit on the system of the bodies, it isn't even remotely suitable for use as "the only parameter in a model, which gets set to a constant value". (What other bodily function works so simply? What makes digestion so bizzarely unique that it can be modeled so simply? None and nothing.)

(And a rather pointless limit in some ways, too... nobody is running around claiming that the human digestive system is an over-unity perpetual motion machine, so making such a big deal about thermodynamic limits is rather silly.)

Re:Why Calorie Counts Are All Wrong by dragonwriter on Monday August 17, 2015 @12:02PM (#10073914)
> That's a contradiction.

No, its not.

> The entire idea of "calories in, calories out" is precisely that there is no difference and all calories are exactly the same.

The idea is that they are the same to the extent that net calorie consumption, irrespective of source, determines weight loss. Effects on satiety and other effects which influence the ability of the dieter to adhere that come with different calorie sources are not ruled out by "calories in vs. calories out" approach, which doesn't hold that all calories are equal in there influence on your ability to maintain a diet regime, but only that they are equivalent in their effect on your weight when you consume them.

This is not to say that "calories in vs. calories out" is right or useful, just that this particular effect isn't inconsistent with it (though it is one of the less important reasons its of limited utility.)

Re:Why Calorie Counts Are All Wrong by iopq on Monday August 17, 2015 @11:56AM (#10073847)
That's not true. If some calories are not absorbed, then they're not really "in", are they?
Re:Why Calorie Counts Are All Wrong by baakss on Monday August 17, 2015 @12:01PM (#10073901)
This partially expresses what I wanted to reply.

The other part is that food calories are the amount of energy needed to raise the temperature of one kilogram of water by one degree celsius. By that definition, calories in vs calories out seems pretty darn close to reality, and if it's not perfect, it's likely so close you're not going to notice a significant difference.