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by sph 1406 days ago
It's not absurd, quite the opposite. "Calores-in, calories-out" on the other hand is laughably reductive.

If the body was an actual furnace, calories in calories out would be an excellent mantra.

But it is not. It's a complex chemical machine with complex feedback loops. You do not ingest pure energy, you ingest matter that might be processed into food and stored using a ton of different chemical pathways, some more efficient than others.

If I ingest 2000 kcal of cellulose, I indeed get 2000 kcal of cellulose out, not as energy but as undigested faeces. If I ingest 2000 kcal of fat, my body behaves completely differently than if I ingest 2000 kcal of pure carbohydrates, than if I ingest 2000 kcal of pasta.

So, please let's stop with his reductive CICO meme. We all know thermodynamics, but it's a very bad model for explaining how the body handles food, hunger and long term energy storage. Focusing on calories is like comparing vehicle speeds by solely focusing on their horse power. There's a relation, but it conveniently ignores hundred of other variables that might show an opposite outcome.
1 comments
alldayeveryday 1406 days ago
No, it is also absurd. To carry your example forward, it would be like someone saying "the idea of horsepower when it comes to vehicle speed is not just antiquated, it is just plain wrong!'

The shape of the car, as a variable effecting the vehicle speed, does not make horsepower plain wrong.

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sph 1406 days ago
I'm not saying thermodynamics is wrong, and I've never said CICO is wrong, please re-read my comment. I'm saying it oversimplifies.

An RC car with 10 bhp is faster than a truck with 20 bhp.

Putting 1000 kcal of kerosene in your engine has a completely different effect than 1000 kcal of diesel.

A 2000 kcal diet is not like another 2000 kcal diet, unless it is composed of the same foods, and the two subjects have a similar genetic makeup and gut flora.

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alldayeveryday 1406 days ago
Right, and my comments are not about your POV. They are addressing the claim of the doctor from the Harvard article who is saying that CICO is wrong, and then responding to your comments about whether or not her claim is absurd. In truth, we cannot prove or disprove whether the claim is absurd as this is a subjective claim. And so I suggest we focus instead on the validity of the claim rather than our subjective opinion of it. To that end, it seems we are in agreement that the doctor's claim is not true.
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mister_mister 1405 days ago
Actually that is right. Horsepower is quite meaningless, engines of today with same horsepower will out perform 40 years old engines in all metrics that are important to us.
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alldayeveryday 1402 days ago
> all metrics that are important to us.

what does this even mean?

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mister_mister 1400 days ago
It means that are other metrics such as torque, Fuel economy, Noise/Vibration, Power-to-weight ratio.

Here is a link to the metrics. https://en.wikipedia.org/wiki/Vehicular_metrics

Here is video explaining why horsepower doesn't really make that much sense. https://www.youtube.com/watch?v=gC2-JKO0c2I

Just like calories, horsepower doesn't explain much.

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