A Premature Declaration of Success
Our Glorious Victories are Getting Closer and Closer to Home
I've been assuming that "PUFAs make mice fat" isn't obvious from the medical literature.
It should be very obvious indeed, if it's true.
A child should be able to do this experiment:
Buy two large cages and some mice. Mix up the mice at random and divide them between the cages. Feed one lot of mice a diet heavy in PUFAs. Feed the other lot a diet that contains saturated fats in place of the PUFAs. Let both sets of mice eat ad lib, and keep them supplied with food, as much as they can eat.
Wait for a bit, and then weigh the mice.
Since the difference between saturated fats and unsaturated fats has been, to put it rather mildly, of some considerable concern to medical "science" over the last seventy years, I've just been assuming that this experiment has been done, and that the difference wasn't obvious.
That's fine, mice's natural diet probably contains PUFAs. They eat all sorts of cold things, like earthworms, that probably contain PUFAs, so they should deal with PUFAs pretty well. Doesn't mean we can.
But my sources inform me that these experiments have indeed been done, and that mice do indeed get fat on PUFAs.
I am having a certain amount of trouble believing my sources.
Because if it's true, it should be known.
And if it's known, then maybe someone in medical "science" should have wondered if it was important.
I think this is the first time in my whole life that anyone has (even implicitly) accused me of having too much faith in medical "science".
So I am faced with the unenviable task of trawling through the literature looking for studies that bear on this question, and adding them all up to find out whether it's true or not.
This is known as performing a meta-analysis.
I do not have the skills to perform a meta-analysis.
Amongst my weapons are laziness, arrogance, hubris and contempt.
That is the wrong toolkit for this important work.
A man truly skilled in the performance of a meta-analysis can make it come out any way he likes. It is known. That's one reason why I don't trust the medical literature as far as I can throw it.
And I sure don’t trust myself to do it right.
But let us accept, arguendo, that PUFAs make mice fat.
Then I have to ask:
What the holy hell?
Why on earth isn't this just settled science? Why on earth is our food full of PUFAs?
Why do the goddamn food labels list "saturated fat" percentage like it was a poison even though it obviously isn't, but not mention "polyunsaturated fat that for the avoidance of doubt will make you really fat and ill just like it does in mice"?
If it's true that PUFAs make mice fat, then we are done, surely.
PUFAs are the cause of the obesity epidemic, and probably all sorts of other horrid things besides.
We don't clear PUFAs very well usually because we're eating lots of protein (probably isoleucine in particular) and if we stop doing that then we can start to burn off the PUFAs and everything just gets better fairly rapidly.
Once the PUFAs are gone we can even start eating lots of protein again.
We are done.
Almost everyone who tries "no PUFAs, low protein" will see their weight normalize to the historical level where BMI is about 20 on average, and probably see a whole host of other health problems clear up.
This diet will inevitably go viral. Every fad diet goes viral. One that actually works will have a great game-theoretic advantage in fad-diet space.
Eventually no-one will be fat or ill any more.
A few decades after that, medical "science" will notice that a few bloggers have solved one of the great mysteries of medical "science" and claim all the credit for it, and in fact it will turn out that that's what they were saying all along, if only we had had the wisdom to see.
(Also ha, ha, slimemoldtimemold, we said it wasn’t lithium. Still, A Chemical Hunger was an inspiring read)
Yeah, I believe it.
Come on guys.....
What is wrong with this picture?
The observation that mice fed diets high in polyunsaturated fatty acids (PUFA) versus saturated fats become obese, while humans are often advised to consume PUFA for health, certainly seems paradoxical at first glance. Let's break it down with a skeptical lens.
1. **Species Differences**: *Hmm, mice aren't tiny humans. Their physiology is different.* Mice and humans metabolize fats differently. What causes obesity in mice might not have the same effect in humans. For example, mice have a higher metabolic rate and different lipid processing mechanisms.
2. **Types of PUFA**: Not all PUFA are created equal. Omega-3 and omega-6 fatty acids are both PUFAs, but they have different effects on health. Omega-3s are generally considered anti-inflammatory and beneficial, while excessive omega-6s (which are more common in Western diets) can be pro-inflammatory.
3. **The Role of Diet Composition**: *It's not just about fat types, but the whole diet.* In studies, the context of the entire diet matters. Mice studies often use highly controlled diets, which don’t fully replicate the complexity of human diets. The impact of PUFA might differ in the context of a balanced diet containing fiber, protein, and other nutrients.
4. **Quantity and Quality**: The quantity of PUFA and the overall diet quality in humans matter. Excessive calorie intake, regardless of fat type, can lead to obesity. Also, processed foods high in PUFA may have other unhealthy components.
5. **Long-term vs Short-term Effects**: Mice studies often look at short-term effects, while human dietary guidelines consider long-term health outcomes. Short-term weight gain might not correlate with long-term disease risk.
6. **Generalizing from Animal Studies**: *Mice studies give clues, but they're not conclusive for humans.* Animal studies are a starting point for understanding biological mechanisms, but their findings need to be interpreted cautiously when applied to humans.
7. **Epidemiological Evidence in Humans**: Observational studies in humans have shown that diets high in certain types of PUFA (like omega-3s) are associated with reduced risk of heart diseases and other health benefits.
8. **Clinical Trials**: Controlled trials in humans provide more direct evidence. Many have shown benefits of PUFA-rich diets in reducing risk factors for heart disease.
In summary, while mouse studies are valuable, they can't be directly extrapolated to humans due to physiological differences. The current dietary recommendations for PUFA intake in humans are based on a large body of research, including epidemiological studies and clinical trials, which generally indicate health benefits, especially when replacing saturated fats with PUFA. *It’s a complex picture, and dietary advice must be nuanced.*
The rodent studies showing that 1% vs 8% LA content makes the difference with total fat content held same are referenced here:
https://tuckergoodrich.substack.com/p/does-linoleic-acid-induce-obesity
> It should be very obvious indeed, if it's true.
> A child should be able to do this experiment:
> Because if it's true, it should be known.
So adorable :)
Did you think this whole time that we were in a "race to find the truth" with Big Science? Of course not. Big Science has no interest in finding out what causes obesity; it'd ruin the whole racket.
It is trivial to test this. It has been tested. A child could do it.
And yet, it's been swept under the rug. When I talk to Actual Serious Scientists about it, they pretend they didn't understand the question or misheard me or radio silence.
I talked to Lamming, the guy who runs the lab with all those isoleucine studies, about this - hey, all your mice are on a high-PUFA diet, even the control mice have 3% LA and seem prediabetic from the glucose tolerance test!
He said he thinks his mice are only 1-2% LA. Turns out he didn't know how much LA is in corn oil, the main fat source in his control chow.
They wear CICO/fat tinted glasses. They cannot see the truth if you hit them over the head with it.
After over a decade on keto, following a bunch of interactions between ketoers and Big Science, I believe very strongly that a lot of mainstream scientists are straight up crooks. They're dishonest, they will lie, they will misrepresent their own findings. Maybe they believe their own lies, though it's hard to see how that could be possible.
Kevin Hall, THE big shot in U.S. nutrition science, likes to post a study of his titled something like "All diets work exactly the same," the title image (!) of which shows that low-carb diets work 30-70% better than low-fat diets.
He also published a study saying "high-fat ketogenic diet is obesogenic." The study: he compared a junk-food "high-fat" (=mixed) diet to a low-fat, practically vegan diet ("Whole Food Plant Based"). The high-fat people ate like 700kcal/day more (IIRC) yet lost the same amount of weight!
Physics defied! First law of Thermodynamics broken! CICO disproven! Right?!
No. Obviously, his finding was "Ketogenic diet is obesogenic by causing increased caloric intake."
He is simply a liar. Maybe he believes his own lies, which would make him a zealot, but there's no functional difference.
You seem to believe in the Efficient Market Hypothesis of Science - if it was easy to demonstrate, it would be common knowledge. I believe the Market for Science is completely rigged, and it is not at all efficient.
There are tons of these experiments. Grant from https://ggenereux.blog/ literally did the experiment you mentioned, just with vitamin A - he bought rodents, put them in cages, and didn't feed them any vitamin A. They never, ever got vitamin A deficiency. It's so trivial a child could do it, yet science "knows" you couldn't possibly survive for more than a few weeks without vitamin A.