Have you read anything from SMTM? Their work has been on HN a few times and they dive deep into the rabbit hole of what causes obesity. Fascinating stuff. https://slimemoldtimemold.com/

i hadn't actually; which posts do you recommend

You want this one:

https://slimemoldtimemold.com/2021/07/07/a-chemical-hunger-p...

A series of mysteries as to different features of the obesity epidemic, that could possibly narrow down the causative factors. For example, people in higher elevations tend to be thinner than those in lower elevations, so perhaps the bad chemical is flowing downriver and accumulating at lower elevations.

thank you very much

Anecdotal but it was simple for me. The cause was seed oils and sweeteners and they are in most processed foods. I stopped eating them and then, a few months later, I stopped gaining weight. Instead my body now seems resistant to gaining weight, even when I eat poorly for a short interval.

It is interesting because I actually eat more macros (carbs, fats, etc) now than before but don't gain weight, which indicates to me there is a qualitative component that often isn't accounted for.

Correlation is not causation. I'm curious which seed oils you are referring to here, am not familiar with common seed oils in processed foods. It doesn't make sense to take in more "macros" but not gain weight, while keeping caloric output the same. There's certainly a component not accounted for but would assume it's behavioral (something like less processed foods means more physical activity or something)

Calories as a concept is bunk science. It was since the beginning. A better generalization is "garbage in, garbage out" (qualitative).

That's a bold claim. Calories as a concept can be derived from the principals of Thermodynamics, to which the human body adheres. The conception of calories does however ignore the body's natural response to calorie restriction, and is therefore incomplete.

Food calories / caloric consumption, as an idea, are a gross, erroneous oversimplification of bodily processes to the point of being bunk science.

This is correct.

Any weight loss / weight gain regime that doesn't consider, at the very least, thyroid hormones is bollox.

Steroidal sex hormones can play a role, particularly female sex hormones.

Allergies too.

typically the mechanism by which thyroid hormones are understood to affect weight gain is through appetite (calories in) and metabolic level (calories out) so they probably aren't really an exception to the calories-in-calories-out model

i mean as far as we know they don't enable you to digest carboxymethylcellulose or anything like that (one of the many common additives on my suspect list)

it's not totally inconceivable; some commensal enteric bacteria can digest carboxymethylcellulose, and they generate heat when they do so, and at least when it's cold outside that's heat you don't have to generate by shivering or physical activity, and we have such a poor understanding of what affects the intestinal microbiome that it's actually possible that thyroid hormone levels are important, but there's no evidence suggesting that this is the case as far as i know

I will now trivially demonstrate how thyroid hormones have an impact on gut microbiome:

Thyroid hormones regulate metabolic rate, and have an effect on appetite.

Everything you eat effects the gut microbiome.

How could it be otherwise? Even putting any amount of even a nontoxic nondigestible substance in will have some effect due to displacing something that should be there instead, at least from a surface area interaction effect.

That might not always be clinically relevant, but it's still important to keep in mind in a clinical setting.

The idea that we don't fully understand, or that there is an absence of evidence in the face of the unknown, doesn't mean we should disregard.

Also, I argue strongly that there is almost always a significant, and generally untreated, psychogenic component to disease.

How could it be otherwise? Or bodies are basically not that different from other mammals, but our minds drive us to do the whackiest things.

Calories can't explain why I can't live off of drinking gasoline, despite the bomb calorimeter showing it to be highly caloric

Calories are an simplified approximation, where your body handles things in the same way as a fire does.

Calories are bunk in that there's a random function between the thermodynamics your body adheres to, and the thermodynamics the food adheres to. One with properties like the total calories your body has access to must be less than the total in, but for a specific food, or a specific meal, the total calories could be larger than the food in the meal, if it makes other calories easier to process, or even a negative, if it makes you puke.

I know this is a bit hyperbolic to prove a point but it brings to the surface a point which so far goes unaddressed: the modulation and variation of metabolic efficiency.

Between the consumption of glucose and gasoline, there exists a spectrum of efficiency in the conversion of thermodynamic calories to useful bodily energy.

Take glucose for example. It's thermodynamic and metabolic calorie values are nearly equal (15.5MJ/kg or 3.7kcal/g). On the opposite end is gasoline, thermodynamically it's 46 MJ/kg but it's 0kcal/g if one were to ingest it. There simply isn't a metabolic pathway to extract energy from gasoline in human physiology.

I have no reason to doubt that the ratio of thermodynamic to metabolic efficiency varies amongst individuals, over time, and in the presence or absence of other compounds. When 9-14kcal/day supports the maintenance of 1kg of body mass in equilibrium, it's clear that, ceteris paribus[1], minute changes in metabolic efficiency can explain rather large differences in human mass.

1. Truly. Even/especially in the absence of differences in consumption.

"Seed oils and sweeteners" are two radically different things. Do you think there's some common underlying mechanism, or that both just happen to be bad in completely unrelated ways which somehow both have the same result of encouraging weight gain?

i might be wrong about this but since sesame has been cultivated for seven thousand years throughout the middle east and india i am guessing that seed oils generically are not a significant part of the cause, though i'm not aware of a traditional diet that gets the majority of its calories from sesame oil (like the hadza with honey or some inuit diets with meat)

but there are lots of other seed oils that have become much more popular in the last half-century that are more plausible suspects, like cottonseed oil, sunflower seed oil, and safflower oil

i think rapeseed oil is probably not it because its popularity is more recent

Probably a very large difference between a sesame seed, and sesame seed oil that's been extracted (which I believe involves a chemical process)

it involves squishing the seeds and has probably been the principal use of sesame for seven thousand years

It is the fat profile of seed oils that is the problem, at least in my investigations. We are consuming certain fats in very high quantities now that we never did historically.

it's possible, but it seems a bit far-fetched, given the enormous variety of fats used in different traditional diets that didn't cause obesity epidemics

there was a lot of excitement about ten years ago that the ratio of n-6 unsaturated fats to n-3 unsaturated fats might be the key, but that doesn't seem to have panned out

It should be noted that sesame is a top ten allergen in the US and top three in Israel (where it is very common) and so don’t rush out to replace all your oils with sesame

it also has a strong flavor and a low smoke point, so hopefully nobody would; it would make a terrible replacement for olive oil, butter, grapeseed oil, lard, aceite de dende, sunflower oil, etc.

the fact that somebody else might be allergic to it doesn't seem like a major consideration for whether i should cook with it though

unless they're coming over that day

No, I have no reason to believe they are connected directly, just both are bad in the quantities consumed when eating processed foods.

Triggering excessive inflammation (either systemically or locally in the gut) seems like a plausible common mechanism, even if the mechanisms by which that happens are completely different.

For me it was carbs and sugar, while especially sweeteners have not been a problem at all.

Yea, whatever ends up working for you. I've done low carb diets, and they worked for me up until they didn't. I haven't been able to sustain them for over a couple of years at a time.

This year will be my 10 year anniversary on keto ;)

Congrats! That's an impressive number of years to stay on keto.

i recently started dating someone who's been on keto for 20+ years

I didn't even remember it was that old (researched it a lot before I started, but mainly focused on studies about the effects and issues, not history, plus, well, 10 years ago). Must have been hard on the early days without easily available nut flours and tons of recipes online.

she likes doing difficult things. she's pretty amazing actually

it turns out it's more than a century old; see https://en.wikipedia.org/wiki/Ketogenic_diet#Diet

what were the most important practices for you getting started on keto

Not living in the US where there's a ton of added sugar in things that don't need added sugar.

Though now the disadvantage is that things like low carb wraps are not a normal store item, and neither monkfruit not alluose are allowed as food in the EU.

But I guess by far the biggest part was actually that I've been working from home since 2008 and love cooking ;)

Or alternately you simply started being aware of what you were eating, and consequently consumed less calories.

No, I've experimented with diet for over two decades, this isn't some new realization.

Also, as I mentioned, I'm eating more calories now, not less. Calories are bunk as an idea anyway, so that point is moot.

Calories (a unit of measure) are not bunk as an "idea" but the relationship of food Calories and weight gain/loss are highly complicated.

An appeal to complexity isn't really helpful. The human body is complex but the causes of widespread obesity aren't, IMO.

Please show me the person who can defy the laws of thermodynamics

Specifically for the calorie model?

Eat a plastic shoe. There's more than enough calories in a shoe to keep you going for a day.

This misses the point that the calorie model is bad for weight related things. The point where the calorie model could apply is for an irrelevant amount of calorie restriction

> but even lab animals are getting obese, despite never picking up the phone to order pizza

This is surprising to me. Do you have a link to a definitive study? Seems it would be easy to pinpoint what is going for lab animals since they have a controlled diet and environment

i don't; i got the assertion from some slatestarcodex post iirc

please let me know if you find it or if i'm mistaken

It's mentioned in the A Chemical Hunger series of blog posts, which were on Slate Star Codex at some point:

https://slimemoldtimemold.com/2021/07/13/a-chemical-hunger-p...

The paper is linked to and discussed a bit here:

https://skeptics.stackexchange.com/questions/52923/have-lab-...

I had a quick look, and couldn't find any other papers or commentary confirming or refuting this.

this is great, thank you very much