Against Low-Carb Diets


I usually put some interesting facts here, but I don't know what would that be here.


My Essay against Low-Carb Diets

So, I will make a response to common arguments made by proponents of the low-carb diets. I have read something about it, and it seems to me it's a dangerous diet fad. I have made a few YouTube videos about related topics, but it seems to me it's a lot of effort with minimal gains in popularity, so I will write a blog-post this time. First, let me address something to my fellow vegetarians reading this: this will not be particularly useful in propagating vegetarianism, because very few people who are against vegetarianism actually believe in low-carb diets. So, don't just point people to this without making sure they actually believe in low-carb diets, otherwise, they are going to feel misrepresented. Equivalently, if you aren't a vegetarian, but you also don't believe in low-carb diets, don't feel insulted, I am in no way implying the quotes I respond to here are likely to represent you.
So, for those of you who are unaware of what low-carb diets are, let's start with a little history. In ancient times, a standard treatment for epilepsy was fasting, completely or mostly abstaining from food for extended periods of time. Of course, as you probably realize, medicine back then was not really based on science and was in many, if not most cases, worse than useless. The standard treatment for many diseases was bloodletting, which continued all the way up to 19th century. Bloodletting was counter-productive in most cases (it was even used to treat anaemia), and in those few cases it was effective (high blood pressure...), it merely alleviated the symptoms. Yet, the wrong tradition continued for millennia. Then, in the early 1920s, a physician called Russell Morse Wilder came up with an idea that, since a diet low in carbohydrates and low in protein has similar physiological results as fasting does (hypoglycemia and liver producing ketone bodies), such a diet could also be helpful against epilepsy. So he coined the term ketogenic diet, as a diet that makes your body run primarily on ketone bodies rather than glucose.

Acetoacetic acid, the simplest ketone body
Namely, in case you didn't know, our cells are capable of getting energy not only from glucose (via mitochondria), but also from fatty substances called ketone bodies. Producing energy from ketone bodies is actually evolutionary much older (dates back before eukaryotes), but it's rarely used in modern organisms because producing energy using mitochondria is much more efficient. Protein restriction is needed because your liver can convert some types of amino-acids into glucose, and, in fact, it regularly does so, because that's triggered not only by actual lack of glucose in blood, but also in response to fructose and saturated fat, which make your liver behave as if there was no insulin (production of which is triggered by glucose) in blood. And, as many of you probably know, converting protein into glucose has a side effect of producing very low-density lipoprotein, the most dangerous form of cholesterol. Human body can't convert fat into carbohydrates. Only certain species of plants can convert long-chain fatty acids into cellulose in case photosynthesis fails, which is then used not for energy, but for cell division. So, basically, a ketogenic diet is one that is based mostly on avocados and coconuts, and possibly a little meat (but not too much meat, because of the protein restriction).
Nearly 100 years have passed, and science still hasn't found an answer to the question how can ketogenic diets or fasting possibly help against epilepsy. And more we know about human brain, less plausible it seems that fasting or ketogenic diet help against epilepsy. Anti-diabetic drugs that result in hypoglycemia don't appear to be effective against epilepsy, and neither do the drugs that cause the liver to produce ketone bodies (acetone, as we know from the studies on rats, probably has slight anti-convulsion properties, but only at dangerous levels far above the levels liver would ever produce). Also, the computer models of the brain predict that it should have a slight negative effect on epilepsy, since ketogenic diet raises the levels of β-hydroxybutyrate, which in turn raises ATP levels and prevents the potassium from getting into neurons at the same time. Higher ATP levels give the neurons more energy (so they can fire more intensely), while the lack of potassium inside neurons makes them malfunction (fire when they aren't supposed to, and that should lead to seizures). High-quality studies are, just with any supposed diet cure, difficult or impossible to make because they are very hard to single-blind, yet alone double-blind[1]. The only double-blind study about that that I am aware of has failed to find a statistically significant effect of diet on EEG-detectable seizures, and the effect of the diet on the subjectively reported frequency and severity of the seizures was right on the margin of error. Those studies that show it works, of course, nearly always also show it also increases kidney stones[2] risk by at least 10 times (as ketones usually cause), problems with concentration (because human brain is basically made for a high-starch diet and doesn't work well without starch), high cholesterol (because the fats in coconuts and avocados are for the large part saturated fats), and so on. It's a little hard to tell apart fact from fiction about whether ketogenic diets help against epilepsy in some patients. It's also hard to tell whether there is a time and place for such non-science-based treatments. Certainly not as the first resort, or as the second or third resort, but maybe as the last resort. But it's not at all hard to tell that the idea that we should all be eating a ketogenic diet is fiction.

Robert Atkins
In the early 1990s, a physician named Robert Coleman Atkins came up with an idea that we should all be eating a diet that's low in carbohydrates, but not necessarily low in protein. That's called Atkins diet. He came up with the idea that starch, along with sugar, is to be blamed for many diseases. In other words, that we should be eating a meat-based diet. Of course, physiologically, blaming starch for diabetes makes about as much sense saying that the cholesterol you eat is to be blamed for heart disease. Most of the cholesterol in your blood is produced by your liver in response to saturated fats, and that's especially true if you have high cholesterol. And some cholesterol is produced in response to fructose, very little of it is the cholesterol you eat. The same is true for glucose: the dangerous spike in glucose levels after eating sugar is not caused by the glucose in sugar, it's caused by the fructose in sugar making your liver behave as if your glucose levels were much lower than they actually are, and mistakenly convert glycogen and protein into glucose. Starch doesn't contain fructose. In fact, of foods that are commonly eaten, only sugar and honey contain large amounts of fructose. Saturated fat also slightly raises the glucose levels in your blood, possibly more than starch.
In spite of the fact that the Atkins'es ideas weren't well-received by the experts, and the fact that Atkins soon died from heart attack (probably caused by his diet), his ideas actually got rather popular among the American public. There still are quite a few popular bloggers that advocate meat-based diets. I am going to respond to the arguments against vegetarianism made by the blogger DietDoctor here. Here we go:

No human population in the history of civilization has ever been recorded surviving on a vegan diet.

Even if that is true (and not everybody would agree with that), that's using a soft science to contradict a hard one. You don't use some empirical science to contradict mathematics, you don't use astronomy to contradict particle physics, you don't use biology to contradict chemistry, and you don't use anthropology to contradict nutritional science.
Besides, it works both ways. Has there ever been a society which ate a ketogenic diet? You advocate eating coconuts and avocados, does that have a long tradition?

The vegan diet is nutritionally insufficient, lacking not only vitamin B12 but deficient in heme iron and folate (meaning that we should refer to it always as a "vegan diet plus supplements").

This coming from somebody who advocates a ketogenic diet... 😁 Tell me, where would you get vitamin C on a ketogenic diet? From supplements, right? If the vegan diet is to be blamed for vitamin B12 deficiency in the developed world, then so is the low-carb craze to be blamed for the recent rise in scurvy in the developed world. WebMD, which I see no reason to think is biased, does that. Food from which people used to get vitamin C, such as potato and orange juice, is now being demonized, and this affects the way people eat, mostly negatively.
B12 deficiency has more to do with people living in more sterile environments than with the diet. It's raising around the world, together with the meat consumption. The danger of getting infected with bacteria from plants is way greater than the danger of B12 deficiency, so we kill the bacteria that produce B12 in the plants we eat.
Oh, and, heme iron? 😕 As far as I know, according to the mainstream nutrition, heme iron is the bad form of iron that causes colon cancer. Why it is that so many studies show red meat causes cancer, but that white meat and fish doesn't? The main difference between them is, well, the heme iron.
A common claim by those who advocate meat-based diets is that micronutrients are supposedly better absorbed from meat than from plants. Well, I see no reason to think that's the case, other than the bias. It's well-known rabbit meat takes more vitamins to digest than what can be absorbed from it. While it's true that most plants containing calcium contain oxalates (preventing calcium from getting absorbed), calcium in milk gets absorbed... into blood, but not in the bones (for cow's milk contains little to no vitamin K, because cows can synthesize it themselves), and it's possible if not probable that it causes heart disease in humans. Another common argument is that DHA (the form of omega-3-acids found in meat) protects against heart disease better than ALA (the form of omega-3-acids found in plants). But, here is a thing, there is no evidence either protect against heart disease.

A near-vegan diet, in rigorous clinical trials, invariably causes HDL-cholesterol to drop and sometimes raises triglycerides, which are both signs of worsening heart attack risk.

The idea that HDL protects against heart disease is a new one and is not really supported by science. We have a way to, to simplify, turn LDL cholesterol into HDL cholesterol and it's called omega-3-acids. Yet, studies repeatedly fail to prove omega-3-acids protect against heart disease. If omega-3-acids don't help, then moderate drinking (moderate amounts of alcohol raise the HDL but not LDL) doesn't help either, and saturated fats are certainly harmful.
Besides, why do you think clinical trials are the most rigorous form of nutritional science? The most rigorous form of nutritional science is obviously mechanicistic evidence, taking knowledge from harder sciences and applying it to nutritional science. But you clearly don't value that, since mechanicistic evidence is clearly against your claim that starch is to be blamed for various illnesses of today.
Besides, there are both rigorous clinical trials that suggest meat-based diets help against type-2-diabetes, and there are also equally rigorous clinical trials, often cited by Neal Barnard, which suggest a low-fat high-sugar diet helps against type-2-diabetes. That strongly suggests rigorous clinical trial means little to nothing when it comes to nutrition (at least partly because they, unlike in medicine, can't be properly blinded). And using that phrase rigorous clinical trials when it comes to nutrition is quite emotionally abusing to people like me.
There is a time and place for nutritional studies, when something can't be determined with data from harder sciences. For example, you can't determine, using only harder sciences, what usually happens when people go vegetarian, for example, whether many vegetarians replace meat with sugar, butter or coconuts (all worse than sometimes eating meat). Let's face it, most people are uninformed about healthy eating, even significantly misinformed, or simply don't care (they think diet-preventable diseases won't happen to them). Attempting to determine that with nutritional studies has some merit. Attempting to contradict much of what we know about physiology with nutritional studies supposedly showing saturated fat don't cause heart disease or that sugar doesn't cause diabetes doesn't have a lot of merit.

Over the last 30 years, as rates of obesity and diabetes have risen sharply in the U.S., the consumption of animal foods has declined steeply: whole milk is down 79%; red meat by 28% and beef by 35%; eggs are down by 13% and animal fats are down by 27%.
Meanwhile, consumption of fruits is up by 35% and vegetables by 20%. All trends therefore point towards Americans shifting from an animal-based diet to a plant-based one, and this data contradict the idea that a continued shift towards plant-based foods will promote health.

And almost the same argument is used by those who claim sugar doesn't cause diabetes, here:

It has become fashionable in recent years to blame sugar for many health problems. However, per capita sugar consumption has actually been falling in the United States since 1999, when bottled water and sugar-free beverages began to edge sodas off the shelf.

So, by the laws of logic, either both of them are right, or none of them are right. I don't know how somebody who has studied nutrition or something related to that can find those arguments convincing, to me it seems worse than the anti-vaccination nonsense.
First of all, how did you acquire those numbers? They seem wildly wrong. I don't know about America, but, in Croatia, in the 1990s (30 years ago), there was a bad food shortage (it was war time). And it was easier to survive on a village because you could grow your own fruits and vegetables. Home-grown fruits and vegetables made most of the diet for most of the people. Eggs being down is believable, since many people in the 1990s were having backyard chickens, but fruits and vegetables being up or red meat being down really isn't plausible.
Second, even if this is true, this ignores the even-more-obvious long-term trend. You know how the emperor Hui Jin was talking If they have no rice, let them eat meat. and was thrown out of power because of insulting his own people like that? Or when Marie Antoinette was talking If they have no bread, let them eat cake.?

Third, even if there were no obvious long-term trend, it would still be the anti-vaccination level nonsense of The rise of autism around the world appears to be correlated with the rise of vaccination.. Correlation does not imply causation. The reason autism is on the rise is that women today give birth when they are older and women who give birth older have a greater chance of having a child with autism or other congenital complications. Similarly, people long ago didn't live long enough to get type-2-diabetes or heart disease, people who would have gotten type-2-diabetes or heart disease simply died of other illnesses while they were young.

There's the entire Indian subcontinent, where beef is not eaten by the large majority of people, which has seen diabetes explode over the past decade.

And you said you don't like epidemiological studies, but that you only take rigorous studies seriously? How about little consistency here? 😐
Besides, what's your evidence that total saturated fat intake is lower in India than in the US? I see no particular reason to think that's the case. The milk intake is about the same.

Nutrition is something we are forced to make decisions about every day. Yet, people don't know much about it. And much of what people think they know isn't true. Nearly everybody believes rabbits like to eat carrots and lettuce, when those are dangerous for rabbits. Nearly everybody thinks mice like to eat cheese, when cheese is lethal for mice even in small amounts. Nearly everybody thinks spinach is a good source of iron, when it isn't (lentil is a far better source). As such, people are extremely vulnerable to nutritional pseudoscience.
And this really makes me question my basic principles. In school, we are taught to value free speech. As in, if there is free speech, the information is going to overcome all misinformation. But when that doesn't happen? What when, on the Internet, you hear nonsense such as Sugar doesn't cause diabetes. and Saturated fat doesn't cause heart disease., but you don't hear reasonable responses to that? I think that what's going on is that nutritionists think they have better things to do than to respond to such arguments on the Internet, and that it takes way less effort to produce such nonsense than to refute it. We are taught nobody should be forcing people to eat in a particular way. But what when there are huge externalities to dietary choices people make they are spectacularly unaware of? If people choose to eat meat from factory farmed animals, there is the huge externality of what the animals have to go through and of the antibiotic resistance. Governments don't have an excellent track record of basing their beliefs on science, but still they have a way better track record than an average person does, and probably any particular person does (for they employ experts in various fields). Those are really tough questions. On one hand, we are bombarded with evidence of a lack of free speech having horrible outcomes (Great Leap Forward Famine...). On the other hand, as somebody who has published peer-reviewed papers in some sciences, such as linguistics and computer science, I know very well that science works precisely because there is a lack of complete freedom of speech there: there is a censorship system called peer review which prevents bad ideas from being expressed. Maybe there is some fundamental difference between government censorship and peer review, maybe those who do peer review tend to be much more competent than the governments are, and maybe they don't create this It's being hidden, so maybe there is something to it. mentality. But, still, things like this make me question my core principles. It's a tough question whether my libertarianism is compatible with accepting science. It's undeniable that government can sometimes make people eat more healthy. Before the regulations requiring salt to be iodized, thyroid illnesses caused by iodine deficiency were very common, and now they are extremely rare. On the other hand, it's also hard to deny governments sometimes make things worse. Governments usually subsidize milk and sugar industries, and spread the misinformation that sugar and milk are harmless in the amounts they are consumed today, when they clearly aren't. Also, what we are taught at school about nutrition may be worse than useless. After I read my 9th-grade biology textbook, I was under the impression that the only thing that raises your cholesterol is the cholesterol you eat, when it actually plays very little role. We were also taught that refined carbohydrates are to be blamed for the rise of type-2-diabetes, when I'm yet to hear a plausible scientific explanation of how they can be. We were also taught fructose was harmless and glucose was bad, when exactly the opposite is true.


[1]Some people might say we don't need blind experiments for that because we supposedly know epilepsy doesn't respond well to placebo. Well, first of all, we know it somewhat responds to placebo, about 7% of epileptic patients who receive placebo become seizure-free, while only 1.2% of untreated patients do. Second, blinding and controlling the experiment is a good thing (if not necessary) even when there is little human factor involved. Unblinded and uncontrolled experiment is what convinced McArthur Wheeler (a man who robbed a bank with no visible attempt to disguise, thinking rubbing his face with a lemon juice, an invisible ink, would make him invisible to the cameras) that rubbing his face with lemon juice will make him invisible to the cameras. Blinding and controlling the experiment (doing it both with water and the lemon juice, photographing both times, and wearing glasses so that he can't tell what is lemon juice and what is water while rubbing his face in that because of lemon burning his eyes and water not as much) would have made it obvious that something was wrong with the experimental setup, and the same applies here.

[2]People who advocate ketogenic diets, as well as other people who advocate low-protein diets, often claim it is not the ketosis that causes kidney stones in people following low-carbohydrate diets, but too much protein. According to them, protein you eat lowers you blood pH, which causes your bones to release calcium in an attempt to neutralize it. Furthermore, that calcium then goes into your kidneys, causing kidney stones. That explanation is not supported by evidence. The most obvious problem is that, well, if protein is to be blamed for kidney stones... how come do kidney stones appear to form significantly more often in people following a ketogenic diet, which restricts protein intake? Also, studies find little or no effect of protein on bone density. Osteoporosis is much more easily caused by a lack of Vitamin K than protein in the diet. Since protein you eat has little to no effect on bone density, it will have even less effect on kidney stones. It is astonishing how the proponents of diet fads manage to contradict mountains of evidence with blind speculation, and how many people end up believing them.

UPDATE on 02/04/2022: I have made yet another YouTube video against low-carbohydrate diets. If you cannot stream it, you can download the audio.