"The seed oil theory is something of a successor to the (mostly leftwing) concern about “trans fats” that popped up 10 to 20 years ago."

That's a weird spasm of both-siderism on your part, Matt.

The campaign to reduce trans fats was not primarily directed against obesity but rather against heart disease, because transfats have an outsized impact on atherosclerosis, I.e. the deposition of fatty plaques on coronary arteries.

And so far as I know, the research that showed that transfats caused greater atherosclerosis was extensive, solid, and still holds good today.

So: you are comparing speculative, YouTube conspiracy theories about "seed oils" making us obese, to well -established research showing that trans-fats cause heart disease, all so that you can say, "the leftwing does it too!"

Not good.

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I like to think of how each decade’s reputation is really just about baby boomers’ point in their life (50s idyllic boring suburb life, 60s a time of discovering drugs and sex and music, 70s partying a bit too hard, 80s time to make money) and adding in the 80s/90s oh no we’re gaining weight in our 30s and 40s is funny to me.

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An illustration of this -- my grandmother was a phenomenal cook and one of her best dishes was fried chicken. I would try to re-create her fried chicken but the first step in the recipe as it has been passed down to me is "get all the grease you can afford." I'm not sure how to approach this as -- not to brag or anything -- I can afford a lot of grease.

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"Lisa, there's absolutely no record of a hurricane hitting Springfield."

"Yes, but the records on go back to 1978, when the hall of records mysteriously blew away."

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Take the obesity rate among children:


It’s quadrupled since 1980. And it’s not some smooth increase over decades. It’s pretty flat and then it starts rising in 1980.

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I think this data is consistent with the layperson narrative: We’re fatter because we can afford more food—including less healthy food, rich in previous luxuries like sugar and fat—and we work more sedentary jobs due to technology advancements. The seed oils, chemical obesogens, and other mystery causes are generally fringe theories. And I imagine that people who care enough about these false narratives to act on them are likely also engaging in other more productive behavior such as avoiding sugar and exercising more.

Nonetheless, a proper understanding of the cause hasn’t led to widespread success in solving the problem. I think most people know that we should eat less and healthier, and also exercise more. (And we should!) Yet knowledge alone is insufficient. I get the impression that most people who put this understanding into practice have their own obsession with diet and exercise, in a manner with some similarities to the seed oil nuts who incidentally also practice some actual healthy behavior.

Speaking from my own experience and that of my friends, maintaining a healthy weight requires a fair amount of conscious focus. It’s certainly do-able, but it demands dedicating a significant amount of time and effort, which seems to be best facilitated by compulsion. I’m thankful that I’m once again addicted to cycling and home cooking, yet I wouldn’t generalize that as advice for the broader population.

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I don’t think the question is so much what the cause of obesity is, as much as what medical interventions will pop up to reverse it (if any).

Im more interested how obesity intersects with culture myself. There has been a great push to destigmatize obesity, yet it’s still looked as a problem to solve.

My personal interest is in the relationship between testosterone and weight gain among men. Last year I found myself gaining weight. Long story short, I got diagnosed with low testosterone, went on oral testosterone pills, and basically had my life changed. My belly fat is virtually gone after 6-months.

I am also hearing about other drugs (one for diabetes) that many people are using off-label to lose weight.

Anyway... fitness is my thing now.

Oh and hi guys. I’m on my way to Michigan State with daughter for a visit. She is checking out colleges.


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I agree that food accessibility is surely a major contributor. What about physical activity? What percent of Americans are able to sit for 8-12 hours a day compared to 20, 40, 60 years ago? I know caloric intake is a much bigger lever on weight that caloric output, but it does seem like it would also be a factor.

And to everyone sticking to the idea that something really did shift around 1980- the nature of a complex system is that one or two inputs can continuously, gradually change over time and you can start to see exponential growth in an output variable. The appearance of a step change in an output doesn’t necessarily mean there was a step change in an input.

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I missed yesterday's tax discussion due to travel. So I will weigh in on yesterday's topic today. My apologies for being off topic.

The fundamental problem with our tax code is that it is riddled with spending priorities rather than merely a tax code designed to raise needed revenue. The mortgage interest deduction, EITC, deductions for children, etc are all spending priorities.

A better solution would be to tax all income equally (or perhaps a lower rate for some types of income to spur investments) and then spend government money on people who need it, either through services or direct monetary payments. This wouldn't necessarily mean a change in the distribution of after-tax and after-transfer income -- we could design a system with either more or less progressivity as today.

The flaw in this plan is that it would make it much clearer to all Americans the level of taxation required to fund desired spending levels, which is why it wouldn't ever happen.

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Have replied to a few posts, but thought it worth giving some general thoughts on this post and on your recent "Bad takes" podcast as the two go hand in hand.

First, I think you and Laura are underestimating how often doctors give genuinely bad diagnosis or advise to patients regarding losing weight and/or obesity. What's especially odd, is in the podcasts Laura actually gives a personal anecdote in this regard! She notes when she was younger she had a back issue, went to the doctor to get it checked out and was then told to lose 10 lbs. She correctly noted this was not particularly good advice for a variety of reasons. But then oddly hand waved it away as some random thing that happened to her. I really think it's worth exploring that this sort of interaction happens a lot more in doctor's offices around the country than either of you might think.

Which leads me to my second point. I think we need to really distinguish here between "Hey I could stand to lose 10-15 lbs. because I put on a little weight over the holidays or I'd like to look good for my upcoming trip to the Bahamas" and "I need to lose 50 lbs because my doctor told me that my heart rate doesn't seem right and it's likely related to my weight and it's seriously increasing my risk of heart attack". One problem with this discourse is these two things get blended together. Someone with a little bit of a gut his lumped in with the person who is seriously obese as though the two are the same. In fact, there is some evidence out there that being slightly overweight is not even the worst thing health wise https://www.scientificamerican.com/article/could-a-few-extra-pounds-help-you-live-longer/

Which leads to my last point. The focus of this article and podcast was talking about obesity on a medical level. And you were specifically talking about an article in the Times decrying the new recommendations from AMA so to a certain extent I get it. But the topic of "obesity" really needs to encompass how the topic is discussed in newspapers, TV and pop-culture generally. The diet fads you discussed are popular in large part because of people like "Oprah" platforming these things (see entire rise of Dr. Oz). Furthermore, the pushback against "fat shaming" is really more about how fatness is treated in society at large. It's just unambiguously the case that lots and lots of people have been pushed to very unhealthy diets and eating disorders due to friends/family/classmates being jerks or even just making a thoughtless comment.

I actually think this is another case where having a more female prospective would be valuable. Body-shaming is definitely something that occurs to all genders, races, sexual orientations, etc. But I think I'm on pretty solid ground in saying women get it worse then men. Like, it wasn't THAT long ago that "heroin chic" became a body type in the modeling industry. Like I really don't think you can talk about this topic without talking about things like eating disorders and body shaming more generally.

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So now comes the obvious question - Why do some wealthy countries have higher rates of obesity than others (i.e. Japan, Italy vs US, UK)? All have abundant food but the outcomes are different.

Not that you can change an entire food culture but would be a good guide to better eating.

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Don't you need to remove changes to average height over time as a confounding factor? People have been getting taller over time due to better childhood nutrition -- and taller people weigh more. Taller people even have higher BMI for the same body shape because BMI is a very crude metric that doesn't perform well at the extremes.

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I like "Bad Takes," but it goes on too long, gets repetitive especially when you and Laura agree too completely. Yes, some of the length is properly nuancing the initial refutation, but still, you might think about shooting for 10-15 minutes less.

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This whole post is sort of weird. I barely mentions the problem that most people are worried about, and which jumps out in the cohort chart, which is the great increase in the percentage of the population in the obese category (BMI > 30). I have not looked up the underlying data, but the picture I see is not so much one of continuity but of a genuine increase in the slope of the top couple of curves. Why has the rate of increase of BMI increased, and why is that increase limited to the upper deciles of each cohort's weight distribution? I'd like to see a chart where the vertical axis is not BMI, but the first derivative of BMI.

Matt puts a lot of emphasis on increasing affluence as the cause of increased weight, and I am sure that is true for the lower deciles, that is, those who are severely underweight because they can't afford enough to eat. Fewer of them: Great! But what role does income play at the top end? What about all the stuff we read about weight, wealth and gender (fat rich men, thin poor men; thin rich women fat poor women)? I'd like to see some charts by income decile.

I think this needs a more nuanced follow-up. As is, it seems to be saying "nothing to see here, folks" when in fact there is a lot to see that this just sweeps under the rug.

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Lots of comments of what we eat, but *when* we eat is also important.

I was a child in the People's Republic of Poland in the 80s, and we as a population were much slimmer than America today. Yes, there were fat people, but you hardly ever saw the kind of extreme obesity you routinely see in the U.S.

And one glaring difference between Poland then and America now is that back in Poland it wasn't socially acceptable to shovel food in your face at any time of day outside of mealtimes. With some exceptions, it just wasn't done. And the exceptions were "go to a nice cafe, order a pastry on a plate (a real ceramic plate, not a disposable one) and a cup of coffee, slowly eat your pastry and drink your coffee while sitting at a table and relaxing, then go about your day." It was not "grab a bag of chips/candy/whatever and shovel it down while running errands or driving or whatever." I think being more mindful about when we eat would help a lot with obesity.

I say this as someone who routinely snacks on sugary food when tired or stressed, so this is definitely a "do as I say, not as I do" comment.

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Feb 2·edited Feb 2

Just look at photos from the 70s of a crowd of adults or a high school year book, those folks were thin.

Also the slime mold post’s main point was that something caused this sudden change. Possible culprits include but are very much not limited to lithium. The point about elevation is that if there was an environmental contaminant you would expect to find people living downstream to be heavier than folks living upstream - and that’s what we see.

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