Thermodynamics is undefeated, people cannot just manifest mass. It must enter through the mouth.

The mouth. That magical orifice where the cake enters and the excuses exit.

Believe it or not, it's also largely where the weight exits, as the C part in CO2. Something like 85% of it.

> An adult typically removes approximately 0.8 to 0.9 kilograms (840 to 900 grams) of CO2 from the body each day.

https://biologyinsights.com/how-much-carbon-dioxide-do-we-ex...

Ok, that is way more than the dozen grams per day I thought it was.

It's one of those initially unintuitive things that makes perfect sense when you consider that "burning calories" is... pretty literally burning calories. Of course CO2 is how most of the mass goes away.

Similar to the "trees are mostly made from air" thing.

There are several multiple that cause sudden weight loss or weight gain with no change in lifestyle and eating. And then there are sicknesses that affect hunger regulation and surrounding hormones (including anorexia actually).

For those that want to stick with thermodynamics, imagine an organism that stores 1% of consumed calories as fat, and uses the other 99%, and that cannot - for whichever reason - turn fat back into calories.

Completely in accordance with thermodynamics, and yet, "just eat less" doesn't work.

> cannot - for whichever reason - turn fat back into calories.

That organism has been outcompeted (darwinized-out) long ago by other organisms that are able to.

Being more specific, humans are not that organism.

Organism, not species.

Ok, Mr. Pedantic. Can you find me one of these organisms, or is this another spherical cow moment?

> there are plenty of conditions and imbalances that can cause weight gain besides "eating in excess"

There are no fat children in those places in Africa where they go hungry. And I guarantee you a lot of people have conditions and imbalances there.

There are absolutely fat kids in Africa, and widespread malnutrition / starvation isn't really a great public health option.

My point is, unless you have found a way to break thermodynamics, the only way to reduce your weight is by taking in less than what you excrete out, regardless of deficiencies and conditions.

Sure. But we know that some conditions, both physical and psychological, can make that process much harder. (Medications, too! And billion dollar companies who employ experts in breaking your will.)

"Just abstain" approaches have failed repeatedly and conclusively in public health. Hell, it's hard enough to get people to wash their hands after pooping and get vaccinated.

Personal experience: the first time i took buproprion/naltrexone it became clear to me why people that arent and have never been overweight think "just eat less move more" is the only advice you need.

> eat less move more

That's not the only advice. But, without that piece, you are unlikely to make progress. Hence all other advice is secondary to it.

You, earlier: https://news.ycombinator.com/item?id=46499273

> The mouth. That magical orifice where the cake enters and the excuses exit.

I don’t think you’re a font of nuanced advice on fitness.

Yeah, just like telling a heroin addict that getting clean is easy, just stop doing heroin.

Oh except the heroin is available literally everywhere and you need to do just a little bit every day to stay alive

Except it's not typically very effectively actionable advice.

It's more in the realm of "just be happy" to a depressed person. Sure, that'd help a lot. It's the how that's tough. So we move the levers that aren't rusted solid first.