Hacker News Reader

Comment by colechristensen | Hacker News Reader

God, that's a lot of writing.

One, you absolutely can "outrun" a diet. If you've known anyone a little bit too much into fitness then you've known someone who has struggled to eat enough to maintain and build weight.

I had a friend who would drink a gallon of whole milk a day to maintain weight because he did so much at the gym.

I'm not saying it's healthy, but saying it isn't possible to exercise so much it's difficult to keep weight on is stupid.

Any beyond this, with tiny homes in dense neighborhoods and social norms that require parents to literally be watching their children 24/7 usually in their tiny home... yeah... the children are fat and depressed.

Lock kids in cages their entire lives and they have emotional problems and weight problems. Then you talk about physical activity like it's "training" and something that has to be scheduled and measured and doled out in just the right doses.

Normalize children having safe space to be by themselves outside in the world without constant surveillance and maybe they won't have so many dopamine addiction social media problems and obesity.

View on HN

> I had a friend who would drink a gallon of whole milk a day to maintain weight because he did so much at the gym.

That's around 2.4k calories.

That's like three slices of costco pizza and a large coke. I can do that like 3-4 times and I am not even that fat.

And that's like half to a third of the absolute peak. Like the rock who basicaly works out all day, eats 5-7k calories.

The point is there are people that are eating large fries and triple thick milkshakes as snacks driving from place to place because it makes them feel happy instead of just eating to feel full. And you just can't outrun that.

I'm not understanding your math?

3-4 times that would be 7200-9600 calories a day, already more than your example of the Rock.

Regardless

> The point is there are people that are eating large fries and triple thick milkshakes as snacks driving from place to place because it makes them feel happy instead of just eating to feel full. And you just can't outrun that.

Yes, if you eat more calories than you expend, because you spend your time eating while driving, instead of exercising, you wont expend more calories than you consume.

That doesn't change the fact that a human can exercise enough that they have difficulty maintaining weight even after eating significantly more calories than necessary for normal maintenance weight.

Nothing about the human metabolism circumvents thermodynamics

His point is that it's significantly easier to go way over the maintenance calories compared to making up with exercise if you just eat whatever you feel like. Essentially that you can consume X calories much easier than you can exercise it out.

With proper diet I'm pretty sure the limit would be like 160kg for a healthy (TBD) body. Strongmen, when I watched regularly, were 160-185kg, with somewhat unhealthy bodies. If you eat junk, that limit comes lower since you can't exercise as efficiently. If you work 40hrs a week, that limit goes down further, since you can't live in the gym and hospital/sport clinic.

Of course, realistically, the sweet spot is IMO in the middle. Don't replace water with blended ice cream but also don't live in the gym or focus too much on it. Dry scooping teacups of some sketchy preworkout called "eXTREME PsYcHo SUPREME ViOlEnCe" with a bunch of other sketchy pills that make your third leg point at people all day and make your skin itch probably isn't worth it.

You literally can. You just need to burn more calories than you take in. It would be difficult but not impossible and is simple math and thermodynamics.

The thermodynamics argument misses the fact that our body is not a single input, output engine. The body will use energy from several different sources, with different efficiencies. It will store energy in different forms, with different efficiencies, and it throws away a lot of energy that you put into it.

Yes, if you spend energy, it has to come from somewhere, but it's only in really specific scenarios that it comes from fat. No one is measuring how much they actually burn either, so we are all just theory crafting that someone burnt X and put in Y so they should be losing fat stores. Maybe they burned Y from blood sugar, super efficient, before it was stored into fat, great. Or maybe they stored it as fat overnight, and they are burning 98% of their breakfast from bloodsugar and only 2% from fat stores. Some people's bodies will have them completely tired out before they even hit their fat, that's a lack of fitness not a caloric deficit.

In general yeah, thermodynamics wins, but the details do matter.

You are completely wrong because over the long term, thermodynamics isn’t just a theory — it’s the governing principle. No matter how “inefficient” the body is at using or storing energy, it still obeys conservation of energy. If you consistently burn more calories than you consume, your body has to draw on stored energy (fat, muscle, glycogen, etc.) to make up the difference. That’s not up for debate — it’s been proven across thousands of controlled metabolic studies.

Yes, the short-term details can vary — sometimes you’re burning glycogen, sometimes fat — but over weeks and months, a sustained calorie deficit always results in weight loss. The body doesn’t magically create energy out of thin air because its “efficiency” fluctuates. You can argue that diet composition and hormones affect how easy it is to maintain that deficit, but not the fundamental physics behind it.

So while you’re right that biology is messy in the short term, thermodynamics still wins every single time when you zoom out.

It doesn't matter what source you are burning your energy from at any given time for long term weight. Let's say you eat a bunch of carbs and then you go for a run, well you're probably going to burn those carbs off first (depending on how hard you run and other factors). Which according to you doesn't matter since it's not burning stored fat. But if you didn't go for that run then those carbs would turn into fat later.... And if you go for a really long run (or you take it easier) then you will start burning the stored fat. But either way it doesn't actually matter because calories in / calories out still is the determining factor.

you are completely ignoring injuries, deficiencies and genetic particularities.

the human body is not a linear system. it's markedly self-regulated and non-linear, and things can get pretty bad pretty quick.

None of that changes anything that I said

In the same way that we don't rely on the assurance of entropy to mix stew however, thermodynamics is not something to base your diet and exercise plan on. We both know you are technically correct, but it doesn't help you to plan your lifestyle change to know it.

That's why it's a frustrating reduction of the problem, the knowledge inbetween helps us make good decisions that involve a lot more than just the physics of the problem.

For someone I know gets it I can just say "eat less than you move" and that is the whole fitness plan, makes sense, but that's because they are filling in all the details for me. When to eat, what to eat, how much to eat, how much and when to move etc etc.

Of course details matter when you actually implement it in your life

But there are people arguing about the underlying concept of calories in/out being wrong which is just silly

> thermodynamics is not something to base your diet and exercise plan on

Except it literally is. You can use it to figure out exactly how much weight you'll gain/lose over the long term if you track things properly

I was not doing that. I was pointing out how reducing the problem to thermodynamics is not a particularly helpful part of the conversation. I see it a lot, it's not a novel insight but it is often unhelpful.

There are people that do argue against it, which is why I had to even point it out in the first place. If you didn't disagree, you didn't need to reply

Exactly. I'm amazed people are still contesting basic stuff like this. It's not open for debate, it has been proven in many ways. In fact, one can set out to prove it to himself, by just using an accurate enough smartwatch and precisely logging all calories. Over time, the math just math, even if it's off by a few percent that's largely irrelevant and can be attributed to measurement error.

I think people refuse to accept the truth because they feel like it should be a one-time thing when in fact it's a lifelong discipline. Some seems to have it easier but that's pretty much true of everything, people aren't equal in self-control and I think the constant propaganda about "equality" just mess with their heads.

The argument misses the point, is why. It's something you would say to trivialise a complex human problem, in order to sound smart. It's treated as if all the advice people need to lose weight is a Thermodynamics 101 class. Just like how all you need to write software is knowing binary. Technically true, woefully ineffective.

If it helps you understand my point of view, I have been strength and fitness training for 15 years, this isn't a matter of lack of discipline. I understand the human aspect of the problem. People don't learn about the thermodynamic aspect and suddenly it all works out for them, it doesn't help.

I'm not sure what you are trying to say.

Are you suggesting that I advocate for people going through a thermodynamics class so they "get it"? Traditional education isn't very effective even for some trivial matters so I wouldn't dare to propose that. As far as I'm concerned, the vast majority of people cannot learn much of complex science and there is nothing wrong with that.

And I wouldn't advise learning about thermodynamics just to solve a diet/exercice balance problem. In fact, I do the opposite. I tell people interested in the matter about various strategies they can use to control their caloric input and other strategies/motivations they can use to get a minimum of exercice.

But that's largely irrelevant, that's not the point. The problem is the various gurus who spit pseudo-science on the matter, pretending that CiCo isn't a thing and pointing the finger at various other things (sometimes with a sprinkle of truth to make things confusing).

There are many nuances in nutrition but if you don't get the basics right, nothing good can happen. And the gist of the matter is that every human needs to find a strategy that works for him to control his caloric input in relation to his energy expenditure.

One way to do this that is extremely effective is to build an intuition on how many calories most common foods are "worth" but also how much various activities/exercices spend. It takes effort but it is pretty simple and once people have the intuition on the matter they can more easily regulate the intake or exercice more, depending on what's easier/more successful for them. It doesn't necessarily solve some psychological disorders (like addictions and compulsive eating to regulate emotional state) but at least it gives a "roadmap" and a pretty accurate picture on how/why.

I have no idea what you are trying to say but it really isn't that complex of a problem. Humans being what they are make it more complicated than it needs to be.

> I had a friend who would drink a gallon of whole milk a day to maintain weight because he did so much at the gym.

That honestly might be an absorption issue, not an intake issue - you can hit aerobic limits enough for your body to skip digesting stuff & just shove protein directly out of the stomach instead of bothering to break it down.

My experience with this was a brief high altitude climb above 5km in the sky, where eating eggs & ramen stopped working and only glucon-d kept me out of it.

The way I like to think of it is that the fat in your body can be eaten or drank, but needs to be breathed out as CO2 to leave it.

The rate at which you can put it in and the rate of letting it go are completely different.

GOMAD (Gallon of milk a day) has been a standard weight gain diet for decades

It's expected the US Army soldier expends somewhere around 5400 cal in high intensity environments like Combat or even Ranger School. 6,000 calories a day or beyond for the same level of exertion in a cold weather, high stress, high intensity environment.

You can absolutely burn more calories that you take in, especially if stressed and not eating right. Or if simply... overtraining because of various psychological issues. Most people are not overtraining, nor are they in combat. Most.

Weight loss in Ranger School is additionally “aided” by limiting students to 2 MREs per patrol day (2400 calories) to increase stress.

Anecdotally, I lost 26 lbs in Ranger School.

I'll give you my jalapeno cheese and crackers for your strawberry dairy shake

Sold if you provide a rock or something.

> someone who has struggled to eat enough to maintain and build weight

There's a big difference between someone who feels satiated too quickly and someone who has a lot of difficulty feeling satiated. It has nothing to do with how much exercise someone gets. It's also much more difficult to eat large quantities of clean calories (for putting on muscle) compared to eating large quantities of dirty calories (putting on fat).

Exercise definitely affects apetite and in both ways - it can make you eat more or less.

Calories are calories, neither dirty or clean.

Yes, but we measure calories by burning food items in oxygen in calorimeters. Burning fat gives X amount of heat, burning fiber gives Y amount of heat. Fat and fiber both have calories when you burn them in a furnace. But body does not use fiber for calories, you won't get fat on fiber. That is the distinction between dirty and clean calories, not everything burnable will be usable for energy in body and not everything that body actually digests will be stored in fat tissue.

Calories are not calories, because they're a unit of energy, and humans aren't batteries. We "use" energy in the form of countless chemicals and reactions, so things get complicated fast.

It's far easier to instead talk about mass, because one gram is indeed one gram, until humans evolve anti-matter producing organs. If you eat X and excrete Y, your body mass will change by X-Y. If you want to lose 1 kg, you will have to exhale 0.8 kg [1] of carbon atoms (you breath in O2 and exhale CO2).

[1]: There are a lot of different "calorie" molecules in your body, but generally all of them are some combination of C, H, O, which turns into CO2 and H2O at roughly 4:1 ratio by mass. So 80% is lost via exhaling C, and the H2O gets processed by your body normally, and is generally lost as urine or sweat, unless you're dehydrated.

> but saying it isn't possible to exercise so much it's difficult to keep weight on is stupid

It’s not stupid. It’s true.

Simple math, exercise does not burn “that many” calories.

Diet, hormones, and genetics have far larger effects than exercise, relatively speaking.

(Exercise is A+ fantastic for a number of reasons. But a secondary mechanism for weight control.)

Just because it’s possible to outrun a diet it doesn’t mean it’s an accurate or helpful description of what most people are struggling with. If you look at the population of the United States as a whole, and the percentage of people who meet the criteria for obesity, it seems obvious that for the vast majority of people today, the problem is food, both quality and quantity.

As for your swipe at people in cities, I don’t know what to say - the fastest way to lower the amount of “diet outrunning” you and your kids do, is to move to a place where every daily activity requires a car and because everyone drives everywhere all the time, it’s not safe to let your kids roam.

>The myth of outrunning your diet

Let's not move goalposts and continue to argue.

I'm responding to the title and the article.

>Just because it’s possible

So I'm right and you'd like to change the stakes so you can continue to argue the incorrect point of the author. Just stop. It's possible, it's not a myth, the author's thesis being basically incorrect invalidates the rest of the rambling post, try again next time.

If you look at united states you find awful lot of people who are extremely sedentiary. Not just in the "sport", but they drive everywhere and sont have that baseline physical movement you get if you walk or kids go to playground.

> ... then you've known someone who has struggled to eat enough to maintain and build weight.

I'm not trying to strawman here, but I've never met a person like that who was ever overweight at any point in their life.

It seems pretty obvious to me that saying "some people can't eat enough to put on weight / get fat" is a distinct thing from saying "someone who cannot stop putting on weight / getting fatter will almost never be able to lose the weight without adjusting their diet". Do you agree or am I missing something?

You're missing something.

More or less anyone can get to the point of being active enough where their body's ability to absorb calories is a limiting factor. It's not genetic or "some people" kind of thing, everybody has this limit and can hit it and people who are really excited about exercise and do a tremendous amount of it have to have strategies about how to get enough calories in their body on a day to day basis.

It's a lot of activity to get to this point, but some folks have magical thinking about eating.

Anyone absent a significant disability can be active enough to lose weight regardless of diet.

I'm not saying the "go insane and spend most of your free time exercising" is the best course of action, but far too many people have magical thoughts about changing diet or changing activity levels being ineffective for changing body composition.

Getting sat down in a doctors office and being told to do this isn't particularly effective, but that's different from actually doing it being effective.

> their body's ability to absorb calories is a limiting factor

That depends on what "calories" you're consuming (as I responded to another comment, calories are not just calories). If you're getting calories through animal fat, then indeed absorption is a limiting factor. If you're chugging pure glucose/sucrose dissolved in water, then that limit is significantly higher, and you start hitting the physical limit of how much liquid volume can physically move through your body without it being a torture method.

Which actually leads to the primary cause of the obesity epidemic: the prevalence of sugar, and particularly in forms that get directly absorbed into the body.

> It's a lot of activity to get to this point

Yes. Like multiple hours a day lot. That's why it's a "myth". It takes an amount of time, effort, and focus, that isn't particularly reasonable for I'd say almost all people.

Fundamentally, I agree with you that it's possible: I pretty much did it myself with ~12 hours of hard cycling a week, but I just think your take is wrong because it basically boils down to nitpicking "myth".

We live in an age where some people will say they're not lying as long as what they said has the vaguest association with the truth. Let's not contribute to that.

People in these threads are arguing aggressively this "myth" is not at all possible when the truth is lots of people experience it, including yourself.

Let's not dilute the meaning of the word "myth" to mean "its somewhat difficult".

A unicorn is a mythical creature from fairy tales, this doesn't mean the same thing as "the zoo with a unicorn exhibit is a few hours away and pretty expensive".

This isn't some nitpick of a minor detail better described with slightly different wording. It's people passionately arguing a common experience is impossible.

It's not "common".

Go ahead and die on this hill if you want but you're doing it alone and without convincing anyone you're fighting the right crusade.

it's not "merely difficult". it's impossible for vast swathes of the population. if i wanted to lose weight through exercising i'd have to be an absent father. well technically i can i guess.

fasting is simply way better and easier.

for many folks exercising is good to get healthy, not to lose weight.

> It's a lot of activity to get to this point

Like a lot. Like professional athlete level.

Running 50 miles per week is a ton, easily top 1% activity level.

And all you incrementally need is a large slice of pizza, a coke, and a couple scoops of ice cream to make up for it.

> I'm not trying to strawman here, but I've never met a person like that who was ever overweight at any point in their life.

This is an extremely common story for anyone who does through hiking on the Appalachian Trail (or Pacific Crest Trail, Continental Divide Trail, etc.). Quite a lot of people start overweight (although I have no idea what the percentage looks like). Almost everyone ends up losing a very significant amount of weight along the way. It is very difficult to stay overweight on the trail. People are intentionally choosing the absolute most calorie-dense food they possibly can, gorging themselves at every opportunity, consistently eating integer multiples of the standard recommended caloric intake, and are still losing large amounts of weight.

This is definitely an outlier case though.

That's definitely an outlier case.

And despite their choices of calorie-dense foods,

> gorging themselves at every opportunity

is a meaningful qualifier. Carrying your food will lead to restriction, naturally.

> Carrying your food will lead to restriction, naturally.

Eh. Yes, but people on the trail are still regularly eating > 6000 calories a day. If you talk with folks, the limit is often satiety even when not in town (people often simply cannot eat enough calories without feeling sick if they don't pace their eating accordingly), not pack capacity.

I peaked at about 200 pounds, got really into cycling, and then had to put a lot of work into my diet to get back up to 160. I think there’s a bunch of obvious reasons why this is uncommon even if you pretend there’s zero metabolic differences between people, so it’s very hard to say how much it’s something that can’t happen for people versus merely being something that could but doesn’t.

Some people maybe can but most cannot. Even running like 5 miles a day is completely undone by a large frapachino. The difference in an active adult's normal day, like a teacher walking around, and a completely sedentary worker at their computer can be undone with a cream cheese bagel.

And in the US, a bunch of the food that's convenient to buy and eat is "hyperpalatable". You're going to be really hard pressed to lose and keep weight off without deliberately adjusting your diet to support it.

35 miles per week is low milage.

10 miles per day would be more appropriate for someone aiming for a marathon.

If you eat real food and not "frapachino" (whatever that is) it can be pretty hard to eat enough food to keep your weight, without stomach issues.

No, I don't run that much. But many people do even more.

Yeah sure, 35 miles is totally realistic for the average American. Sorry I was too lazy to double check the spelling of frappuccino when it didn't auto-correct on my phone, I'm sure that made it really difficult to tell what I was talking about!

Yes, outliers gonna outlie.

I also know runners that purposely eat at severe deficit to lose muscle mass and be lighter. Which is idiotic, like wanting to lose brain cells to win a chess competition.

i mean it makes sense.

endurance running is about efficiency, not raw power output. it would make sense that you would aim for a strong cardiovascular system, strong digestive system, and a limited amount of very efficient muscles.

looking at pro runners they're all kinda skinny. they optimized their body for the distance.

Your one anecdote definitely invalidates the article. Lol.

2/3 of the US is fat as shit, but hey I'm good at fitness, so clearly its a you problem and not that I'm a freak

Reply on news.ycombinator.com