If you are completely unfamiliar with the actual science on obesity you probably think that's dumb because obesity is caused by high-palatability foods. Read the first page linked if you'd prefer to know why that's obviously wrong.
I admit to being, at present, persuaded by the high-palatability hypothesis, which I roughly translate into the following thesis: "The general rise in obesity is primarily explained by the rise of highly processed, addicting foods, which raises our natural set point, tricking our bodies into eating more calories than we 'need' before feeling full."
I read the posts you linked (you referred to this one, right?), and I'm not convinced by them, but I'm open to people explaining why they think I'm still wrong.
First I'll summarize the article briefly, and then respond to each point.
My brief summary
The series begins by outlining 8 mysteries:
The series continues by arguing that CICO (as in calories in, calories out) cannot explain the current crisis, and cites an array of evidence that tries to argue against that model. Given the inadequacy of CICO as a model for weight gain, then, the reason for the current obesity crisis must be due to environmental contaminants, which neatly fit each of the 8 mysteries.
My interpretation of the mysteries
In my opinion, assuming the high-palatability hypothesis, very few of the mysteries are actually "mysteries" in the sense of being surprising.
For example, we can explain mystery 1 by saying that high-palatability foods have become more common over time (duh). We can explain 3 because very few people are effectively targeted by anti-obesity campaigns, and it's intractable to simply ban high-palatability food (which is probably the only solution that would actually work on a large scale, short of advanced technology). We can explain 4 by pointing out that hunter-gatherers don't eat high-palatability food. We can explain 6 for obvious reasons. We can explain 8 by pointing out that people don't have unlimited willpower, and thus, don't rigidly adhere to a dieting plan when given abundant choices to "cheat" and eat high-palatability food (which is highly addictive).
That leaves mysteries 2, 5 and 7, which I do think call out for more explanation. However,
As far as I can tell, the most surprising mystery is 7. The author presents impressive evidence regarding altitude anorexia, and studies that looked into alternative factors (including carbon dioxide and oxygen).
EDIT: I now think that oxygen is the leading culprit for altitude anorexia, even though the author says it isn't. Their evidence against the oxygen hypothesis is the following: one study found a small effect, and another study was methodologically flawed. Putting aside the second study, the effect found in the first study was not small at all in my opinion; in fact, it found that people who exercised in a low oxygen environment lost about 60% more weight than those who didn't! Scott Alexander has written about this and finds the oxygen hypothesis plausible.
Yet, all things considered, I still don't think that enough alternative hypotheses have been explored to say that mystery 7 is anywhere near conclusive. It's well-known that obesity rates vary by demographic groups, and that there are genetic confounders involved, and demographic groups are also not evenly distributed between high and low altitudes.
In poorer nations, such as China, it seems highly plausible to me that altitude correlates strongly with access to supermarkets and fast-food restaurants that carry lots of high-palatability foods. Urban centers are generally clustered in low-altitude areas, along coasts and alongside rivers. If people in urban areas are exposed to more high-palatability foods, as opposed to more traditional dishes, then it seems obvious that you'll find a correlation between altitude and obesity. The contamination hypothesis is not needed to explain this fact.
My take on CICO
Given that I don't find any of the mysteries very surprising (with the possible exception of 7), I don't see why the contamination hypothesis falls out as a parsimonious explanation of the data. Admittedly, however, my main disagreement probably boils down to the section on the plausibility of CICO.
Being honest, I found many of the parts of the CICO post to be riddled with misleading statements, sometimes simply confusing CICO with the idea that diets and attempts-to-increase-willpower work (which I emphatically do not believe), or strawmanning CICO into a generic position that absolutely nothing other than calories and exercise matter, or that an excess 3500 calories precisely and linearly adds 1 pound of fat to your body.
Obviously other factors, including genetics, matter. Obviously diets do not work on a large scale. And obviously the formula is not as easy as "eating an extra 3500 calories always means you gain an extra pound, even extrapolated to people eating 10,000 calories a day." None of these facts are strongly inconsistent with the high-palatability hypothesis as the dominant explanation of the data. In my opinion, these are quibbles, not knock-down arguments.
And, in any case, the author admits,
Sure, consumption in the US went from 2,025 calories per day in 1970 to 2,481 calories per day in 2010, a difference of 456 calories.
That's a lot! As someone who has very carefully controlled my eating before, I saw first-hand how eating a 500 calorie deficit made me lose weight, and conversely, how eating a 500 surplus made me gain weight. The author seems quick to handwave this fact away, as if a few hundred calories can't add up over time. Their interlude responding to objections on this point also seems handwavey to me, and doesn't give any evidence inconsistent with the high-palatability hypothesis.
Conclusion
Given a biologically plausible mechanism, its consistency with practically all the "mysteries", common sense, and general scientific wisdom (from what I gather), it seems highly likely to me that the high-palatability hypothesis is correct. This, in my opinion, diminishes the case that money should be spent investigating alternative hypotheses (though the value of being proven wrong might be so high that it's worth it anyway).
UPDATE: Be advised that I no longer consider SMTM to be among the things we should be doing, though I don't regret having given them an earlier try. I wish somebody else was running out and trying the sort of things that SMTM is trying, but they're bad enough at analysis to not qualify for further support until that gets fixed. See eg this Twitter thread.
Having not apparently the energy to write this longly, I write it shortly instead, that it be written at all.
People sometimes go about saying now, in this community, that there is collectively enough money that we could potentially go do more things with it, if there were things worth doing.
If that's true, I'd like to see us planting seed grains now for replacing the now-defunct state capacity of the USA and Earth, with respect to biodefense and ultra-high-leverage med R&D.
As a poster child of a previous intervention I backed here, Seasonal Affective Disorder affects 0.5%-3% of the population and higher in countries at extreme latitudes. Call it a hundred million people at a guess. Standard lightboxes don't work very well for treating it. The Sun works great for treating it. Reason suggests trying more light. Earth, however, previously lacked the state capacity to investigate this obvious question of massive scope. I put a private funder in touch with a group that did a preliminary investigation; they need to run a larger study but preliminary results suggest that they may, in fact, need to use more light and that doing so might be effective. Again, that's for a problem that probably over a hundred million people have. So it's not very surprising that investigation of it bottlenecks on there being a single interested medical researcher, who writes Eliezer Yudkowsky as the person who posed that question, and gets funding arranged by that route. It was less than $100,000.
This sort of thing seems obviously competitive to me with QALYs/$ or DALYs/$ on global poverty interventions.
Really obviously competitive, actually. I will not argue the point further because I expect that most readers who can be persuaded found a glance at the numbers sufficient.
EA's ability to do more things in this space, if it is not bottlenecked on money, is very likely bottlenecked on: good ideas to pursue; people who can pursue those ideas; and/or admin staff who can investigate grants, make them, and operate them.
I suspect that people who can do these things are, at the very least, valuable. They should therefore be nurtured even in their earlier stages. If you ever want an apple tree that bears fruit, you may need to at some point plant a seed that doesn't have any apples on it right then, and invest effort into watering it in proportion to how many apples you hope for later, rather than how much this tiny sapling has proven itself right now.
I think it was a huge, huge mistake that more money was not spent on AGI alignment when it was small and weird and unproven. The resulting damage was not something that could be fixed by any or all of the money that became available later. Someday I may write more about this. Anyways, don't do that.
The Rapid Deployment Vaccine Collaborative, aka RaDVaC, is now past the small weird stage. They've pretty much proved themselves. They should be nurtured and scaled up to where they can start to replace US and Earth defunct state capacity to do the R&D that leads up to being able to rapidly design new vaccines that rapidly scale in production and deployment. If we can't give RaDVaC $2M I'd like to know what it's being spent on that's more important. Covid-19 was not very much of a pandemic and if Earth ran into a serious pandemic in its current state that would be a serious problem.
Some weird person [correction: 2 weird people] wants to investigate whether the real driver of our massive planetwide obesity epidemic is lithium contamination, probably in water. If you are completely unfamiliar with the actual science on obesity you probably think that's dumb because obesity is caused by high-palatability foods. Read the first page linked if you'd prefer to know why that's obviously wrong. If you know about the actual epidemiology of obesity and how ridiculous it makes the gluttony theory look, you are still probably saying "Wait, lithium?" This is still mostly my own reaction, honestly. But obesity remains a massive growing planetary problem, and almost nobody is investigating it in a way that takes the epidemiological facts seriously and elevates those above moralistic gluttony theories. If some weird person wants to go investigate, I think money should be thrown at them, both to check the low-probability massive-high-value gamble, and also to encourage them to maybe go investigate something else in the same space if the lithium thing doesn't pan out. $200K maybe. They advertise their effort under the name of Slime Mold Time Mold (SMTM) for no particular reason I can discern. I think this is the kind of decision that some people make when they are small and weird, and I think that if we allow that to prevent us from throwing money at them then we are stupid and not learning from history.
That's all. Writing this up now, briefly and hurriedly, because the
lithium person wantslithium people want to apply for some EA grants. Consider this my recommendation thereof.