Quick review: Nature Wants Us to be Fat

Nature? Never heard of him.

This is just a quick follow-up post to my last one, where I talked about Richard Johnson’s hypothesis that high salt or umami intake can activate the polyol pathway, getting the body to endogenously convert glucose into fructose and all the downstream effects from that.

If you haven’t read it, you can find that post here: A Metabolically Shaped Hole.

I have since read Johnson’s book, Nature Wants Us to be Fat, and thought I’d provide a quick review.

Not that long; don’t need to read it

The book is only about 210 pages long and is written in a light-hearted and engaging style, and I knocked most of it out in a day.

That said, if you read my post and watched his 3 lectures (part 1, part 2, part 3) on Youtube, you really don’t need to read the book.

Everything technical & metabolic is covered in those lectures in great detail. The book merely lays out some of the cited studies in a bit more detail, answers a few frequent questions, and lays out Johnson’s idea for an ideal “Switch Diet” to deactivate the metabolic “survival switch” as he calls it.

The Sweet, Sweet Survival Switch

One of the reason I called my last post “A Metabolic Hole” was that Johnson’s fructose/polyol pathway theory fits almost exactly into the “metabolic hole” I’m trying to fill in terms of hypotheses and mechanisms, and therefore is extremely similar to Modern PUFA Theory (MPT), my main hypothesis as to what caused the obesity epidemic.

Johnson suspects that mammals have a built-in “survival switch” that causes them to divert food into fat storage (obesity), turns down metabolism to save on energy (lowered metabolic rate), increases foraging behavior, turns up inflammation (heart disease, stroke, cancer) and blood glucose (diabetes).

This is great if you’re a bear hibernating through winter, or a fat-tailed lemur going through the dry season in Madagascar (?). Johnson even shows that penguins and whales have and use similar mechanisms.

That’s nearly the exact same mechanism that Brad Marshall from Fire in the Bottle proposes; something in our modern environment is constantly putting us into “mammalian torpor”.

The only difference: Johnson is 100% convinced that fructose is the signal, whereas PUFA theorists like Brad and myself suspect omega-6 PUFA linoleic acid to be at fault.

What’s funny is that you don’t need to go far to find the similarities. The way in which fructose starts to mess with our fuel partitioning is also related to reactive oxygen species. This happens when the liver starts turning fructose into uric acid via the fructokinase pathway, which eventually can lead to the creation of fatty acids and therefore fatty liver disease.

This process actually consumes more ATP than it creates, unlike most (all?) other pathways dealing with fuel substrates in our body. It can therefore create the necessary “fuel partitioning” problem: we “lose” energy even though we are eating, because all the food is going into fat storage. Eating thus actually makes us hungrier! (In general, not just for more fructose.)

This is an extremely similar explanation to Peter’s protons theory at Hyperlipid, which suggests something very similar when beta-oxidizing linoleic acid.

Johnson even observes a phenomenon often cited by PUFA theorists: young kids and animals aren’t immediately getting obese & diabetic from high fructose intake. Their response is measurably lower than that of fat & diabetic animals or humans, but after enough exposure, they, too, become metabolically messed up.

This is the same phenomenon observed with PUFA, where short-term studies don’t immediately show the issues - it takes “saturating” a person or animal’s body fat for several years (in humans, mice obviously faster) until the bad long-term effects show up.

Johnson blames this on the body being inefficient at activating the survival switch at first, whereas long-term fructose exposure makes it both more sensitive and efficient at it.

I wish these fructose and PUFA guys would talk to each other.. oh well.

Conflicting Studies

One thing that was weird/confusing when reading the book is that Johnson has all sorts of studies that “prove” his point that fructose is uniquely the bad guy. And he does have a lot of studies.

The issue is that I have been around the low-carb block long enough to know that there are equal & opposite studies.

Just like he “proves” that fructose is the bad guy by blocking fructose metabolism in rats, I know of rodent studies that fed 60% kcals from fructose, and in absence of high linoleic acid, still didn’t cause metabolic syndrome or obesity.

Similarly, Johnson cites a study in which lard, fed in absence of fructose, did not cause issues. But lard is widely cited by PUFA people such as myself as being uniquely fattening, even in absence of high fructose or even carbs.

What gives?

One particularly curious fact Johnson cites is the condition of Fructosuria, affecting an estimated 1 in 130,000 humans, in which the aforementioned enzyme fructokinase is missing.

This means that fructose cannot activate its special “survival switch” pathway, and these people cannot become fat or diabetic. Apparently, there are zero recorded cases of people with fructosuria having diabetes or being obese.

On the other hand, we have tons of studies “debunking” fructose theory from post-low carb people in rats and in humans, and the timeline doesn’t quite line up with the obesity epidemic…

In other words, “it’s complicated.”

Maybe excess fructose and excess linoleic acid can both activate the switch? Maybe it depends on genetics who responds more to which one?

Certainly, both sugar & seed oils have become way more common in the average human diet since industrialization.

It could be some weird co-factor issue, in which excess linoleic acid makes you more liable to activate the fructose pathway, or amplify its effects.

Or maybe linoleic acid is dry hay, and fructose is the spark?

Sigh. Again, I wish people from different camps would talk to each other. Or even people from the same camp!

Apparently Johnson is good friends with Gary Taubes of low-carb fame. Yet Taubes never seems to mention that eating a high-salt or high-umami diet could activate endogenous fructose production..

Everyone is just super confident in his own “knowledge” and considers everyone else “debunked” and so we never get to the heart of the matter.

I wish these Low-Carb people read the room

It’s almost comical to read this book here and now. Johnson keeps talking about this amazing low-carb diet as if Atkins didn’t come out in the 70s.

Apparently Johnson had written a book previously, The Sugar Fix, explaining why fructose was the bad guy, and how a low-fructose diet would prevent & cure obesity.

With his newfound polyol pathway knowledge, he admits that it’s not as simple as “you eat too much sugar” and how these other factors come into it.

But he still presents the low-carb diet as the solution.

This is funny because all of us on the internet moved on from low-carb to Paleo in the 2000s, then onto keto in the early 2010s, and now most of those have moved onto carnivore or some sort of Ray Peat/Saladino style diet in the late 2010s or early 2020s.

Almost nobody even uses the term low-carb any more as it’s been completely superseded by keto, as far as I can tell.

Certainly people didn’t flee the label because low-carb was working too well?

It’s as if reading a book by someone who hasn’t watched the news for a few decades and just keeps extrapolating from whatever happened in the 90s.

Smear against Stefansson

One thing I particularly disliked was an unnecessary and, in my opinion, idiotic swipe against one of my personal heroes, anthropologist Vilhjalmur Stefansson.

Stefansson is famous in carnivore circles because he lived with Eskimos for months to years at a time, for a total of 4 years if I remember it right. He and colleagues embedded themselves with families, ate with them, drank with them, slept in the same igloos as them, hunted with them, and so on.

Upon returning to New York City, Stefansson and his colleagues explained the fatty, meat-centric diets of the Eskimos and how they appeared to be perfectly healthy. Mainstream nutritionists were in disbelief, they just “knew” you couldn’t possibly be healthy eating only fatty meat and near zero plant matter.

Stefansson and one colleague therefore conducted a 1 year (!) experiment on themselves, the first few weeks of which were under 24/7 hospital supervision. They only ate fatty meat and they were fine.

Now in Nature Wants Us to be Fat, Johnson cites Stefansson as proof that a high-fat, meat diet is unhealthy: he alleges that when Stefansson and his colleague did this, they had cholesterol levels of 800mg/dL or more and that their blood was a thick, white, milky consistency. Further, he alleges that Stefansson “thought he was eating an Eskimo” diet, but that really, the Eskimo diet was much higher in protein.

I find this to be absurdly dumb. If you just look at Stefansson’s wikipedia page, you will quickly learn that he embedded himself and lived with these people for years.

If anyone should know what Eskimos REALLY eat, it would be him. I don’t know which of the handful of studies on Eskimo diets Johnson looked at to make this snide remark, but I’ve seen a meta-analysis from when I made my Swamp Visualizer and it lists individual studies with wildly different levels of protein vs. fat.

Simply declaring Stefansson to be wrong on this just shows Johnson knows nothing about Stefansson, or the topic.

In addition, I’ve read Stefansson’s book Fat of the Land in its entirety twice, in which he details his travels and the 1-year experiment. I don’t recall any mention of 800mg/dL cholesterol, or of milky, thick blood.

Now it’s certainly possible that this is documented history and I just don’t recall it, or that Stefansson didn’t mention it. But I sure would like to see a source for that claim, and Johnson doesn’t provide one.

I will say this pissed me off quite a bit. It’s just ignorant and dishonest.

Johnson on PUFAs

The entire book doesn’t mention different types of fat until page 175 or so, where Johnson briefly mentions that saturated fats are bad (mkay) because they raise LDL, which causes heart disease.

Of course that view has been “debunked” (if that word still means anything) by low-carb, keto, paleo, and carnivore people for generations now. I personally don’t believe it at all.

Johnson goes on to mention the difference between MUFA and PUFA, and that PUFAs can be omega-3 and omega-6. He just briefly recites the mainstream views on each; in short MUFA is harmless but olive oil is better than canola cause flavonoids, omega-3 is awesome and “can counter fructose” (hmmmm I wonder what else omega-3 counters), and that people disagree on omega-6, with some calling it inflammatory, others saying it’s good, and that the balance between the two seems key.

He recommends upping omega-3 instead of limiting omega-6, a very mainstream view that doesn’t make mathematical sense if you really believe in the Omega Balance. But none of these people ever do the math to find out you need to eat 5lbs of salmon a day to counter the tablespoon of soybean oil in your salad dressing.

The Switch Diet

Frankly I’d rather learn more about the Neo diet. I like people who don’t die in the 3rd act. Spoiler alert.

The Switch Diet is what Johnson calls his own diet, designed to deactivate the metabolic “survival switch” or at least minimize its activation, as he says it is more akin to a dimmer than an on/off switch.

It’s relatively standard fare and you probably couldn’t tell it apart from some other mainstream diets if you weren’t looking for it.

1. Obviously, he thinks fructose is bad, and so he wants you to limit sugar, and eat whole fruit instead of soft drinks and candy

2. He advises a mild reduction in high-glycemic carbohydrates like bread or white rice or breakfast cereals

3. He also advises you to limit salt a little bit, e.g. by cooking at home (typically less salty than restaurant/processed food)

4. He advises you to drink water with salty meals to prevent the dehydration that activates “the switch”

5. He advises to limit red meat to 2x a week because of the saturated fat, and because it’s high in umami (glutamate etc) which can activate the switch

6. Same for shellfish, which is apparently really high in umami

7. Therefore he recommends eating poultry, fish, dairy, and plant proteins like soy/legumes more than red meat or shellfish

8. He recommends moderate dairy consumption if it’s not in ice cream (added sugar), because he thinks the dairy can counter the activation of the switch. One exception is hardened/fermented/blue cheese, which becomes high in umami. Interestingly, he believes that lactose is completely harmless and does not activate “the switch” at all.

9. He actually recommends coffee, because it can apparently counter switch activation. Hallelujah! He says dark chocolate and tea have a similar effect.

10. Alcohol is a total no-go, as it uses almost the exact same pathways as fructose. In fact, he claims that alcohol only leads to fatty liver disease BECAUSE it activates the survival switch via fructose. Apparently, you cannot become alcoholic without fructokinase. This means that alcoholic fatty liver disease is actually non-alcoholic fatty liver disease, lol.

All in all, this is pretty milque-toast dietary advice if you ask me. With a few exceptions (dark chocolate/coffee/dairy) this is probably exactly what your doctor would tell you to do.

Sugar bad, high-glycemic carbs bad, vegetables good, red meat bad, poultry/fish good, alcohol bad, legumes/soy good… shocking.

I’ll say this; I like his polyol pathway hypothesis and I believe it could explain a lot of “huh, weird!” moments in low-carb, in certain high-PUFA contexts, and in my personal anecdotes.

But I think if this diet worked as advertised, we wouldn’t have an obesity epidemic.

Legions of people on the internet have failed to lose weight by doing pretty much this. I personally gained 100lbs on a strict keto diet, mainlining coffee, dairy, AND dark chocolate daily, and the only violations of that protocol that I can think of are moderate to high salt consumption and high umami consumption (meat/tomato sauce).

(Also high saturated fat, but he doesn’t think that causes obesity/metabolic syndrome, just heart disease via LDL.)

So if those 2 are enough to counter a hyper-low-carb, near-zero-fructose keto diet with ZERO alcohol in 10 years, extreme dairy, chocolate, & coffee consumption… then that protocol isn’t very effective, isn’t it.

Umami, imami, weallmami

One thought that popped into my head; what if my “reduction in protein” coming from high-beef keto was actually just a reduction in glutamate/umami?

My current ex150 diet is extremely low in protein, but it’s also extremely low in umami except for 150g of beef and the relatively high amounts of marinara sauce I tend to eat.

I also used to eat blue cheese and parmesan-type hard cheeses A LOT on keto. I’m talking several Costco-sized chunks a week, often at least one of them blue cheese.

Maybe I could’ve just switched from beef and blue cheese to beans & chicken breast?

Now there are pretty convincing studies regarding protein restriction, but it is a thought.

Today is day 4 of ex150nosauce, so at least the tomato sauce part is easy enough to test for. I suppose I could try using no sauce and using chicken breast instead of ground beef one day, but let’s not get ahead of ourselves.

I also realized that Monster energy drinks have 380mg of sodium (!) per can, meaning 6 cans alone already put me over the recommended sodium RDA for adult men. I have, at times, consumed 6 cans a day regularly. Diet sodas also contain some sodium, although much less.

Since I don’t add any salt to my meals myself, cutting out diet sodas, energy drinks, tomato sauce & beef is pretty much all that’s left in my diet in terms of Johnson’s “survival switch” theory.

FAQ me anything

The FAQ chapter is maybe the most valuable part of the book if you’ve listened to the lectures.

You could sort of deduce most of his dietary restriction ideas if you just listen to the lectures. But in the FAQ, he answers a lot of detailed questions that are bound to come up. Let me just briefly give you an overview:

1. What about fruits & vegetables? Vegetables are fine, most fruits are fine, just don’t binge on dates and avoid dried fruits & fruit juice as they are highly concentrated. Some flavonoids and other compounds in fruit may actually be on net beneficial. He recommends you eat 2-4 pieces of whole fruit a day.

2. Are sugary drinks worse than sugary food? Yes, absolutely. Johnson says that the rate of absorption of sugary drinks makes them much more likely to trigger the “survival switch.” Cutting out soft drinks seems much more important than cutting out sweet desserts, so do that first.

3. How come some (e.g. young) people can seemingly eat lots of sugar without any downside? Johnson says that it takes some exposure to fructose for the body to “ramp up” the survival switch, and that the more you activate it, the more sensitive and efficient it becomes. This frankly doesn’t make evolutionary sense to me and hints at some other factor (linoleic acid?) in play.

4. What about artificial/non-caloric sweeteners? Most of them are fine (stevia, monk fruit, sugar alcohols except sorbitol) in the sense that they do not activate the survival switch. There are some issues or potential issues with various sweeteners though, and they keep your “sugar cravings” alive, so he recommends limiting sweetener use or cutting them out if you can.

5. What about “sports drinks” like Gatorade, those contain salt? He says these are fine if actually used, sparingly, during athletic events. But don’t drink them if you’re not actually going to need the electrolytes, aka don’t just substitute them for soda.

6. How about reports that giving sugar can improve performance? This is usually more about the glucose, not the fructose. If someone is low in blood glucose or glycogen, e.g. a child who hasn’t eaten breakfast or an athlete about to run a marathon, filling up with glucose can help - to a point.

7. Are some people resistant to fructose? Very few, but yes. There are those 1 in 130,000 people mentioned above who simply cannot use fructose in that survival switch way. Some people seem “culturally” immune, typically tribes living remotely until they move to the big city - where have we seen this pattern before?

8. Can we block sugar cravings? No, but he’s working on it. Or someone is.

On Uric Acid

Measuring

Now most of the downsides of this “survival switch” seem mediated via uric acid, and uric acid has long been a target of clinical monitoring and control due to gout. Gout is caused by crystallized uric acid in joints, causing pain & inflammation.

Funnily enough, this was one of the first points of contention I learned when I got into low-carb 20 years ago. The mainstream wanted you to believe that red meat causes gout. But we, the smart low-carbers, knew that fructose causes gout!

Funny, 20 years later, it seems they were both right.

Anyway, I obviously looked around to purchase a home uric acid meter. Turns out that’s surprisingly difficult. One website tested several available meters, and nearly all of them were incredibly inaccurate, to the point that the website said they were beyond useless. Think off by 4 points on a scale of 0-6.

The one meter that they rated highly seems out of production, and the website looks like it hasn’t been updated since the 2001 dot-com bubble. I tried to contact them, and their contact form explicitly tells you not to ask about when the meter will be available again. Seems end-of-life.

Some other meters seemed to be available through Indian e-commerce stores, targeted at Indians in India.

Amazon doesn’t seem to carry any uric acid meters at all. Maybe they became regulated out of existence in the U.S. by the FDA?

There are urine strips on Amazon, but the urine strips for keto are total shit, so I suspect these to not be much better, but I ordered some cause why not.

So far, all of my strips have come back as “low/normal” uric acid. Then again, I’m literally doing ex150nosauce to minimize uric acid right now. Maybe I should test again on a high-protein, high-salt, high-umami refeed?

Lowering

There is also allopurinol, a gout medicine that works by lowering uric acid.

Johnson says that people have tried studying it in relation to obesity and metabolic syndrome, but that the studies are inconclusive. He blames poor study design; it would obviously only work in people who have high uric acid to begin with.

There seem to be some studies that he likes, so it’s sort of a maybe I guess. But I suppose I can’t just ask my doc for this in absence of gout.

Unfortunately, I lost my easy & cheap hook-up for any lab test I wanted a while ago, so I can’t just get my uric acid tested real quick like I used to with various other markers.

Sigh.

How to integrate this fascinating new knowledge?

I do think that the polyol pathway can explain a lot of “huh, weird” moments in low-carb, and in general. I do not think it is The One. I think there must be some context to it, and the context might well be linoleic acid. Or genetics.

Maybe it’s just that you can activate this switch by excess fructose OR excess linoleic acid OR both. Or maybe they supplement each other, or your genetics determine which one you’re vulnerable to.

Or maybe Jaromir is right, and LA makes fructose worse?

In that case, low-carb & the polyol theory would be correct IN THE CONTEXT OF LINOLEIC ACID for some people.

Which is still useful.

After all, we knew it would be slightly complicated.

PS: Shit, this was supposed to be a quick update on the book, and now it’s 3,700 words. I suppose I really enjoy typing.