SMTM "Mysteries"

Why SMTM is wrong about mostly everything

Right, so I hate SMTM. I don’t hate them because I hate novel ideas about obesity, or because I want people to stay fat, or because Morality and Willpower And You Need To Lose Fat The Old Fashioned Way or whatever. I hate ‘em because they misrepresent and say sometimes straightforwardly stupid things consistently, and are consistently not called out for it. So, here is my full-length debunking/roast/critique/takedown of everything they’ve said, from A to Z (well, with exceptions for where the broken clock is right, so forth). I don’t know or care if SMTM is a man, woman, collective, or sentient AI designed to irritate me, so I’m going to refer to them as a singular male, for purposes of cognitive ease. Let’s dive into it: 

People in the 1800s did have diets that were very different from ours. But by conventional wisdom, their diets were worse, not better. They ate more bread and almost four times more butter than we do today. They also consumed more cream, milk, and lard. This seems closely related to observations like the French Paradox — the French eat a lot of fatty cheese and butter, so why aren’t they fatter and sicker?

Our great-grandparents (and the French) were able to maintain these weights effortlessly. They weren’t all on weird starvation diets or crazy fasting routines. And while they probably exercised more on average than we do, the minor difference in exercise isn’t enough to explain the enormous difference in weight. Many of them were farmers or laborers, of course, but plenty of people in 1900 had cushy desk jobs, and those people weren’t obese either.

Ok look, let’s put “conventional wisdom” to one side, since that’s an irrelevant feint. Conventional wisdom matters precisely zero here, as opposed to “theories with which SMTM is in conflict”, the big one here is going to be something like “CICO”, which I’m not going to define, but I’ll take broadly to mean “calories are what matter, primarily weight gain and loss are determined by a ratio of calories taken in through food, and lost through energy expenditure”. I know there are people in ACXD who will, as a retort to CICO, say something like “but thermic effects/but microbiome/but increased TDEE from added energy/but some other effect”. I think it’s trivial that the thermic effect of certain foods (protein, mainly) is a thing, and who knows, maybe the microbiome is doing some funky stuff. I do not expect this to account for the lions share of the action in any case, and also in any case, this is not what is really up for debate here. For the most part, if you eat 2500 calories a day, and that maintains your weight, all things being equal we should expect knocking 500 calories off to lead to approximately 1 pound of fat loss in a week, and 500 calories extra to lead to 1 pound of fat gain. 

To formally put this into “conflict” with SMTM, let’s say that said energy expenditure is not itself altered more than a few percent by random chemicals that we intake through our environment, since I take it this will be the eventual thesis put forward.

With that in mind…. Ok before I dive into how bad their very first damn citation is, some incredibly basic considerations: diets of most earlier centuries contained a hell of a lot more veg than what we now intake. And what SMTM is talking about has nothing to do with overall caloric intake, only with a few “bad” foods, which, again, conventional wisdom is not theory- it’s just an easy straw-fashioned man to harangue to get your point off the ground. Second basic consideration- “effortless weight maintenance for everyone, including those who had cushy desk jobs who weren’t obese either”. Well, I note the total lack of sourcing for this final point- it’d certainly be neat to see breakdowns of obesity stats relative to professions in 1850, but SMTM is not providing that. And what is asserted without evidence…. But, well, speaking of evidence relating to employment stats- https://www.digitalhistory.uh.edu/disp_textbook.cfm?smtID=11&psid=3837 ( I will not claim this is authoritative, but it passes the sniff test for me, and if someone wants to argue with the stats… feel free, I doubt you’ll be arguing over more than a few percentage points). 1860 still has 53% of the population working in agriculture. This will not be light work, for the most part, mind you. This is hard labour, for not-short hours. This is precisely the sort of work where you are upping your caloric expenditure through the day, every day. To say nothing of generating metabolic change through developing some sort of musculature- which makes burning calories easier too. A non-trivial chunk of the rest of the population at this time were also in some sort of hard labour or another. Only the privileged few were primarily in professions which involved spending all their time in a “cushy office”, and I’ve no doubt some of those people did, in fact, become fat. And some of those people aren’t fat still today. So this isn’t a great start, SMTM (for any nitpickers who want to talk about women not involved in the workforce, this probably isn’t going to pass muster for a low-effort sort of lifestyle, in the 1800s. Hopefully I do not have to spell out why). Overall, frankly, physical effort looks an awful lot like a plausible, though partial, account of the different between people today and people 200 years ago, and we can get granular with the differences too- I’d be happy to discuss this on the server, but currently I’m addressing SMTM, moreso than constructing, or rather defending, a particular alternative. 

Onto the data SMTM provide, for the claim that, on the CI front (as opposed to CO, which they glibly toss off and which I’ve addressed in the prior para), people were not eating well. A reminder-

their diets were worse, not better. They ate more bread and almost four times more butter than we do today. They also consumed more cream, milk, and lard.

Go away and read the article they link here. Seriously, read the breakdown first, then the summary of conclusions. I’ll wait. Here it is- https://academic.oup.com/ajcn/article/91/5/1530S/4597478 . Ok, back? Do we see the issue yet? I’ve claimed before that SMTM strikes me as someone acting in bad faith, and this does nothing to disabuse me of the notion.

To summarise why, this very article is addressing increased energy intake from other fat sources. So, ok, butter intake goes down…. This says not much at all if fat intake in general is going up considerably:

 Added fats and oils, total 

16.1 

21.8 

25.3 (17.5) 

39.4 (25.9) 

I don’t know if that formatting is going to come out great in discord but er…. overall fat intake by the lights of the cited study goes up drastically over the time period, it does not go down- and this is indeed the conclusion that the article reaches. That

```The increase in childhood obesity mainly reflects increased energy intake```

is what is said in the first goddamn line. That SMTM quotes an article like this and doesn’t even note that is embarrassing. I honestly wonder if they’re trolling the reader. But ok, my irritation aside, the entire initial mystery doesn’t get off the ground. People are consuming more calories and doing less physical work, considerably. It should be no surprise at all for the CICO-er that the average person in 1850 did not struggle to maintain a lean body (and indeed, often struggled to gain weight- apropos, such people exist today too, and my experience is that they are typically small people who don’t like eating all that much, and who do a lot of cardio. Bodybuilding/bro vernacular for such people is “hard gainers”).

Something seems to have changed. But surprisingly, we don’t seem to have any idea what that thing was.

Come on, at least pretend that you’ve considered the obvious causes here first. We have lots of ideas, some of which seem pretty good! But we’ll get to these. What does SMTM have to say next?

Well: 

Between 1890 and 1976, people got a little heavier. The average BMI went from about 23 to about 26. This corresponds with rates of obesity going from about 3% to about 10%. The rate of obesity in most developed countries was steady at around 10% until 1980, when it suddenly began to rise.

This wasn’t a steady, gentle trend as food got better, or diets got worse. People had access to plenty of delicious, high-calorie foods back in 1965. Doritos were invented in 1966, Twinkies in 1930, Oreos in 1912, and Coca-Cola all the way back in 1886. So what changed in 1980?

First, obvious, note- it doesn’t matter when a foodstuff is developed, if it’s only consumed now and then, as a treat. One twinkie periodically is not making anyone fat. Bare “access” is, thus, irrelevant. Also, quibble, “processed” does not always mean high-calorie. Doritos aren’t low calorie, sure, but like Pringles and similar potato-y snacks, you have to eat 100g (which you’re unlikely to unless you’re deliberately pigging out hard) to get even over 500 calories. Not trivial, but not remotely comparable to some snacks/treats people consume mindlessly all the time. 

https://bmcpublichealth.biomedcentral.com/articles/10.1186/1471-2458-10-746 See Figure 6, Chart F.  (oh a note for those who might object to use of calorie availability data as opposed to like… more nebulous and hard to find intake data... Look, SMTM was happy to earlier, to make their point, so if you are willing to credit them as a source of good epistemics, then it ought to extend here too). Looks an awful lot like calories starting going up around 1980, doesn’t it? In fact, there is a pretty clear “increased energy intake” trendline that starts in the 80s. I can conjure lots of reasons why that might be, socially/economically and just in terms of the foods people shifted toward eating on a regular basis- but however you cut it, CI Line Go Up. 

So, the next charge is “sudden inexplicable rise in BMI/obesity in and around the 80s”, and it looks an awful lot like we have an entirely explicable cause- namely calories and energy intake. So, case closed? 

Common wisdom today tells us that we get heavier as we get older. But historically, this wasn’t true. In the past, most people got slightly leaner as they got older. Those Civil War veterans we mentioned above had an average BMI of 23.2 in their 40s and 22.9 in their 60’s. In their 40’s, 3.7% were obese, compared to 2.9% in their 60s. We see the same pattern in data from 1976-1980: people in their 60s had slightly lower BMIs and were slightly less likely to be obese than people in their 40s (See the table below). It isn’t until the 1980s that we start to see this trend reverse. Something fundamental about the nature of obesity has changed.

Ok this all seems something of a footnote next to what has already been discussed. But just…. fine? It’s not exactly surprising that civil war veterans, or veterans in general, might have (a) developed habits that led to less food intake in old age, and (b) might have wound up poorer on average, and consequently penny-pinching on food. The former is a noted thing with children of rationing and the depression, for instance, and (b) just seems to be common sense. That said, let’s take it for a moment that a trend has really reversed (as opposed to SMTM just inferring a lot from n=1 here) and people are getting fatter into their old age as opposed to getting thinner. Plausibly, even that just seems…. A consequence of the rise in available calories- and all the other partial explanations which are true now and weren’t before, easy processed food which isn’t especially satiating, a shift toward “eating out” as a leisure activity which was culturally less of a thing in the history of the west, greater affluence which means people spend more money going out and eating (and people have more money and more time to waste as they get older, obviously). Note that I say “partial”. A standard SMTM apologist conceit I’ve observed is “well SMTM have shown that all of this doesn’t work and/or it doesn’t explain the sudden shift”- I’ve already given a reason for the “sudden” shift, offering up other factors which might contribute as asides is not the same thing. And if I were hitching my wagon to any of these other factors, I’d not be persuaded by “SMTM said”, since, well, many more of these posts to come. 

Things don’t seem to be getting any better. A couple decades ago, rising obesity rates were a frequent topic of discussion, debate, and concern. But recently it has received much less attention; from the lack of press and popular coverage, you might reasonably assume that if we aren’t winning the fight against obesity, we’ve gotten at least to a stalemate. But this simply isn’t the case. Americans have actually gotten more obese over the last decade. In fact, obesity increased more than twice as much between 2010 and 2018 than it did between 2000 and 2008. Rates of obesity are also increasing worldwide. As The Lancet notes, “unlike other major causes of preventable death and disability, such as tobacco use, injuries, and infectious diseases, there are no exemplar populations in which the obesity epidemic has been reversed by public health measures.” All of this is, to say the least, very mysterious.

You keep using that word, I am not sure you know what it means. Again, I’ve already covered why increasing obesity would not be in the least mysterious- the world is getting more like the parts that got fat a while back. (Oh fun aside, but the global downturn in nicotine use is another argument I’ve seen made- people have actually got hungrier- this also began to really hit in the 80s apparently, as a cultural phenomenon. I don’t expect this to be a huge factor but still…. Interesting side note). 

At any rate, obesity is just… trivially almost, the sort of problem likely to compound. Once you’re really fat, it gets harder to move around, to make sensible food choices, to acquire the bare motivation needed, to get less fat. So we’ve got a set of very fat people and we’re just adding to it, since we have bad strategies at the societal level for dealing with obesity. I’ll reserve “strategies for practical weight loss” for some other time. 

SMTM then spends some time talking about food variety, and about how some tribes live off very little variety. This is interesting anecdote time, but it also just doesn’t matter. I’m not interested in debunking some conventional wisdom I don’t see reason to believe anyway. Maybe variety is useful in ways that one can nevertheless get by without, or maybe it isn’t- but all of that seems inconsequential to weight loss/gain/obesity. So I’ll brush past that. Yes, hunter-gatherer tribes are often pretty lean. This is like, the canonical case of something easily explained by just, calories, pretty much regardless of diet variety and macronutrient balance. 

Oh god, I’m doing this in real time- so I’ve just seen this next bit and where the hunter-gatherer thing is going…. Why am I doing this on Christmas Eve-Eve. Fuck it, my christmas present will be a lot of rationalists telling me I’m wrong. Maybe I should set up a patreon. I’m sure SMTM is getting paid for spreading this nonsense, maybe I should try to get paid for spending time debunking it. Ok stream of consciousness over. Here it is: 

Historically, different cultures had wildly different diets — some hunter-gatherers ate diets very high in sugar, some very high in fat, some very high in starch, etc. Some had diets that were extremely varied, while others survived largely off of just two or three foods. Yet all of these different groups remained lean. This is strong evidence against the idea that a high-fat, high-sugar, high-starch, low-variety, high-variety, etc. diet could cause obesity.

No one, outside of weird, “specific diet” enthusiasts, think that the big problem causing obesity is diets “high in x” and “low in y”, whether that is sugar, starch (I mean seriously, what?) or “variety”. That said, none of this is evidence that a diet high in fat and sugar couldn’t cause obesity. Also “high” is being, you’ll note, used in two subtly different ways here. My diet is “high in fat” if I eat proportionately a lot of fat. But that does not mean that a diet “high in fat” in a more absolute sense could not cause obesity. For an example, as people on The Server probably know, I bulk and cut as a part of bodybuilding stuff… when cutting (dieting, in other words, but with a firm end point), despite Best Advice being not to do this, sometimes I’ll wind up having days which are mostly fat- but I’m eating in a 500 calorie deficit despite 70% of my calories being fat. This is evidence that one can “lose weight” while on a “high fat” diet proportionally, not that one could eat 100 grams of butter 5 times a day and lose weight. Keep that distinction in mind. 

A Tanzanian hunter-gatherer society called the Hadza get about 15 percent of their calories from honey. Combined with all the sugar they get from eating fruit, they end up eating about the same amount of sugar as Americans do. Despite this, the Hadza do not exhibit obesity.

SMTM must be a better researcher than I am, since I cannot find a single reference in either paper which, even be inference, would entail that the Hadza are getting as much sugar as americans are, in absolute terms. In fact this paper- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0040503 literally says the following: “Western diets are certainly more sugar-rich and energy-dense than more “traditional” diets and wild foods [4], [8], [9], many hunter-gatherers seasonally consume a large portion of their daily calories as honey” which, ok sure, “a lot of daily calories as honey”, but look at the “western diets are more energy dense” bit and in the words of EY, meditate and become wiser. It’s an interesting paper, apropos, and says a lot about energy expenditure that people might find cool….. It just doesn’t remotely substantiate SMTM’s point, so far as I can tell. Nor does the other, but since I can’t adequately source proof of a negative, I invite people to just go and read the articles linked. 

And again, the point shouldn’t really be about sugar anyway, but about overall energy/calorie intake- and on this front, SMTM’s own source clearly states that these people are intaking less calories in their diets, overall. All the rest is window dressing. 

The Maasai are an even more extreme example, subsisting on a diet composed “almost exclusively of milk, blood, and meat”. They drink “an average of 3 to 5 quarts/day of their staple: milk supplemented with cow’s blood and meat“. This adds up to about 3000 calories per day, 66% of those calories being from fat. (They also sometimes eat honey and tree bark.) But the Maasai are also quite lean, with the average BMI for both men and women being again in the range of 22-23, increasing very slightly over age.

This is literally the only thing in the whole section that seems remotely compelling, and if it were true, it’d certainly warrant some discussion at least. 3000 calories daily, especially the majority of which being easily absorbed fats, some carbs, and a little protein but not enough for a wild thermic effect…. Yeah. 3000 for active people isn’t obscene, but for people of average height and without a decent amount of muscle mass to maintain that at a BMI of 22… God I’m overusing ellipses here, but I’m saying I’d at least feel like it was worth discussing? Maybe they do a lot of exercise relative to westerners on similar calories? Who knows. Of course, this actually turns out to not be worth discussing, since this source doesn’t lead anywhere. And given my experience of the sources that do lead somewhere, I’m disinclined to extend SMTM the benefit of the doubt on their editorialising. So, this may well just be bunkum. Certainly it’s not a data point readily available elsewhere, and I did go looking nevertheless (update: one prezi slideshow with the same 3000 calorie claim, which also talks about them doing a hella lot of exercise and having some neat tribe-level biological adaptions…. So who knows). 

That’s about everything that matters in that section, the rest is just more “well look some people had varied diets in ways that Conventional WisdomTM would say something about and look, it’s wrong, maybe”, so I’m not going to waste my time. 

Then there is the “animals getting fatter” case. Two links, one about horses which… ok horses get fed by people. So like, I’m not going to count that, or the domestic animals cases (which are used in the other study, which is at least a real study) for much at all. A lot of these cases seem explicable as “they eat our food, and we overfeed them anyway”, at least until evidence is shown for something else. The Royal Society study is interesting though, and it definitely demonstrates weight gain in some animals where you would not expect it. I am going to extend similar scepticism to the possibility of this being something besides “people in modern age being more willing to feed anything they’re interacting with and fatten them up”, but lab cases are hopefully somewhat sterile. The bigger problem is sampling bias. By their own lights, they had to fish around for study-cases. Oh and here was an exclusion criteria: “consisting of animals that were calorically restricted or had their food intake titrated to maintain relatively constant body weights”. Now, this makes perfect sense if you’re not actually trying to look at cases that like, throw out CICO or something, and just care about tendencies to eat more, or lipid-affecting disorders or whatever else. But this is going to rule out the most clinical environments where intervention is actually being taken. And the study itself was just an overarching look at these weight-gain cases. I don’t have much more to say on this. If it was cropping up as part of a better analysis overall, I’d have that context in mind. Here….well, it is something that throws up questions, but these are not questions amenable to the grand mystery SMTM is attempting to construct, by my lights. 

Of course, the very next point they make is about animals that seem to not be gaining crazy weight except when given certain human foods. My analysis here will amount to just four choice quotes, and a hope that readers will brush past the implication SMTM is pushing you toward, and just focus on the actual facts available":

Lab rats gain some weight on high-fat diets, but they gain much more weight on a “cafeteria diet” of human foods like Froot Loops [sic] and salami

The graduate student was inspired to try putting the rats on a diet of “palatable supermarket food”; not only Froot Loops, but foods like Doritos, pork rinds, and wedding cake. Today, researchers call these “cafeteria diets”.

Sure enough, on this diet the rats gained weight at unprecedented speed.

But when you give a rat the cafeteria diet, it just keeps eating, and quickly becomes overweight. Something is making them eat more.

We see a similar pattern of results in humans. With access to lots of calorie-dense, tasty foods, people reliably overeat and rapidly gain weight. But again, it’s not just the contents. For some reason, eating more fat or sugar by itself isn’t as fattening as the cafeteria diet. Why is “palatable human food” so much worse for your waistline than its fat and sugar alone would suggest?

“But again, it’s not just the contents”- why not, SMTM? It’s not the fat that is making people eat more of it, sure. Or the sugar, or whatever else. But could it be that rats (as people) respond more to these well-developed and heavily selected palatable and non-satiating human foods? All that is actually being said here, directly, is that they eat more of this stuff, and get fat. This certainly doesn’t reflect well on modern processed foods but, again, we’re getting a load of innuendo about other effects here, and we don’t need any to explain the phenomenon. 

I’m just going to brush past “Mystery 7” since I’m happy to admit I have no idea what work CO2 is doing here, I leave that to people with more patience for analysis of oxygen and CO2 effects than I. That said, I get the vibe that even SMTM is unsure about this, which isn’t a good sign, given what they have been sure about. 

Mystery 8: Diets Don’t Work 

There’s a lot of disagreement about which diet is best for weight loss. People spend a lot of time arguing over how to diet, and about which diet is best. I’m sure people have come to blows over whether you lose more weight on keto or on the Mediterranean diet, but meta-analysis consistently finds that there is little difference between different diets.

Well, once again, I don’t see any reason why we’re meant to be caring about these random fashionable diets as opposed to calories. I could link a bucketload of studies showing that when diets do work, they work by initiating a caloric deficit. I think Mike Israetel has a compilation of stuff on this. 

Now, 20 lbs isn’t nothing, but it’s also not much compared to the overall size of the obesity epidemic. And even if someone does lose 20 lbs, in general they will gain most of it back within a year.

Yes because people still live in our society, and have their habits, and these things are hard to override. That dieting is hard for quite a few people is just a fact, an unfortunate one at that. It involves a lot of unlearning, at least some willpower, and probably a change of environment and conditions more than anything else. It also probably involves never thinking about debates between “low carb” and “mediterranean” and “paleo” ever again, since if that is your core obsession, you’re playing the wrong game. But, and here’s the rub, “reducing caloric expenditure” does work for weight loss, pretty consistently. Some people have such strong hunger signals that it just gets progressively harder to lose weight even at high BF. I mention that because (a) this is rough for people, and (b) all it really tells us is that brains are fucky and the bits that interact with physiology are also fucky. Plenty more can be said on that- SMTM actually cites someone (miscites, rather, I’ll be getting to that one later, in another addition of whatever-this-is) who talks about hunger-signalling in the brain and related bodily stuff later on. There is a lot of existing theory on this. 

We, thus, have a pretty good idea for a majority of weigh loss and gain, and separately, for how and why people find losing weight really hard in certain cases. 

And…. that’s it. That’s where SMTM caps off their first section, so I will end there too. Thanks for reading through.