The Futility of Cholesterol Denialism, Part 3: A Process of Elimination
I called a chapter of The Primitive Nutrition Series “Anything but LDL” because the cholesterol confusionists would be happier to focus on any possible biomarker that might indicate heart disease risk other than LDL. LDL is the one biomarker that high-saturated-fat diets cannot bring into a healthy range without calorie restriction, and it just happens to be the biomarker that has the most direct role in the pathogenesis of atherosclerosis. They are in a similar state of denial about nutritional factors that are linked to heart disease. Dietary saturated fat and cholesterol are the best understood and most widely accepted contributors to heart disease, but in the minds of the low carbers the blame should go anywhere but there. It must be the wheat. It must be the carbs. It must be the sugar. It must be the polyunsaturated oils. But there is no way fatty animal foods are to blame. There must be a conspiracy against such foods, or medical science must be captive to a shared delusion. Why else would they blame the greasy, fatty, mutagenic, high-calorie, cholesterol-laden foods of animal origin? They seem so innocent.
To illustrate the absurdity of this belief it might be useful to take a historical view of another category of research into heart disease and diet beside cross-cultural comparisons, animal research, and basic cholesterol science.
It is true that animal foods were early suspects in heart disease. Of course, as you have seen in my Cholesterol Denialism videos, a century ago atheromas were observed to be engorged with free cholesterol.
And Anitschkow induced atherosclerosis in rabbits by feeding them cholesterol. Only animal foods contain cholesterol.
Therefore it should only seem reasonable that dietary cholesterol was investigated as a contributor to heart disease. In 1951 a researcher not named Ancel Keys treated individuals with high cholesterol through a low animal fat diet and found that the cholesterol levels of most could be lowered. This investigator also observed that high blood cholesterol was associated with heart disease.
Also in 1951 another researcher not named Ancel Keys conducted a study that indicated that mortality from atherosclerosis could be reduced on a low-cholesterol, low-fat diet.
As for Ancel Keys himself, in 1957 he was conducting experiments on patients in a metabolic research unit, feeding them different types of fat. Among the fats he studied were olive oil, cottonseed oil, and sardine oil. Butterfat caused cholesterol to increase the most.
Later, he narrowed his focus to specific fatty acids, finding lauric and myristic acid to be of particular concern.
Other researchers did the same. Dietary fat in general did not appear to affect serum cholesterol levels, but specific saturated fatty acids did. Did these researchers harbor an anti-myristic acid bias back in 1963? Or did they arrive at their conclusions through honest scientific inquiry? Read the literature and the answer is obvious.
In this 1991 study different sources of saturated fatty acids were examined for their effects on cholesterol. Beef fat, cocoa butter, and butter fat were compared to olive oil. Butter fat raised LDL the most. LDL was lower with the consumption of beef fat, and LDL after cocoa butter was lower still. The lowest LDL numbers were attained with olive oil. Therefore, all those saturated fats are worse for heart health than olive oil.
Here is a table from a 2010 paper relating the effects of different sources of dairy fat on cholesterol. It appears butter is worse for cholesterol than cheese. Butter even fares poorly in comparison to other dairy products.
This study examined 420 dietary observations from 141 different groups of subjects. That’s a lot of experimental data. The authors concluded that Keys was right about saturated fat. It raises cholesterol. However, he was wrong about dietary cholesterol. Dietary cholesterol raises blood cholesterol.
Here’s an interesting cross-cultural comparison demonstrating the effects of saturated fats. Cholesterol levels in boys and men living in 20 countries were measured. Total cholesterol rose with increasing saturated fat intake, and this was most evident in comparisons of boys, who would have had lower cholesterol levels on average than the men. This is one more study showing us that unhealthy food has less of an effect on your cholesterol if you already have high cholesterol. Those living in developing countries and vegetarians ate more carbs and consequently had lower cholesterol.
I am not aware of either Brown or Goldstein ever going vegan, but they asserted that animal fats and cholesterol raised LDL levels.
This textbook states that the molecular basis for the effects of saturated fats on LDL is well understood. Essentially, saturated fat causes LDL to be removed from the blood by the liver at a lesser rate.
One might think that saturated fat’s effect on LDL by itself would be enough to explain how it causes atherosclerosis. After all, if there is more LDL in the blood, there is more opportunity for it to penetrate the artery wall. That’s true, but it’s not the whole story. In this important experiment on mice, dietary saturated fat was shown to increase selective uptake of LDL into the artery wall, even in mice that were resistant to atherosclerosis. Saturated fat caused disease to take root.
Saturated fats have been connected to adverse health outcomes in innumerable studies, some of which fly by in The Primitive Nutrition Series. Diabetes is a major risk factor for heart disease, and saturated fat is linked to that as well. In this study of men with heart disease, saturated fat intake correlated to more body fat and worse insulin sensitivity, unlike carbohydrate.
I have not found any evidence that researchers into the connection between diet and heart disease ever excluded any nutritional factors from consideration. Forty years ago , a scientist at the World Health Organization said that one cannot help but conclude that saturated fats play a role in heart disease, but he said there was no proof they are the only or even the main culprit.
The saturated fat apologists would love for you to believe an important scientist like Ancel Keys had a vegan agenda, or that nutrition science has made an overly simple distinction between animal and plant fats. We should be clear that neither of these were the case. Distinctions have been made not between animal and plant fats, but rather between saturated and unsaturated fats. Furthermore, all saturated fats have not been the subject of concern, but rather a few specific fatty acids, primarily lauric, myristic, and palmitic acids. I just don’t see evidence of any sort of bias at work in the research that implicated these.
Ancel Keys did not set out to raise alarms about animal foods, no matter how much the anti-vegan spin doctors try to make it seem that way. In this excerpt, he did note the correlation between low animal protein intake and low cholesterol, but he resisted blaming the protein itself, reasoning that those low animal protein diets were also low in fat, which he considered to be the real problem in 1957.
Many proteins were studied for their effects on cholesterol. Here, you can see what various proteins did to blood cholesterol in rabbits. Animal proteins were found to raise cholesterol much more than plant proteins.
It does seem that vegetable proteins promote healthier cholesterol levels, yet how often do you hear about this from nutrition authorities?
I’ll mention here that Keys also investigated a range of other non-dietary factors for their influence on heart disease as well, including excess body fat. He did not find a reason to suspect it in 1954.
Nor did he in 1972 after correcting for age, blood pressure, smoking habits, and yes, blood cholesterol.
Speaking of blood pressure, I’ll side track for a moment to respond to one of the more bizarre confusionist arguments. Sometimes the deniers will say that cholesterol can’t be the cause of heart disease since atherosclerosis forms in arteries but not in veins. Since the blood in both types of vessels carries cholesterol, the cholesterol can’t be the cause of disease. The portions of arteries that are subjected to the greatest stress from the force of the movement of the blood inside them are where plaques form. Where the blood is less agitated, plaques don’t form. Therefore, it is the stress from the movement of blood that causes the heart disease, not cholesterol.
The location of disease is an interesting subject. It’s just not an argument against the lipid hypothesis. Yes, it is true that the fluid dynamics of the blood within the coronary arteries seem to be a necessary condition for plaque to form. But tell me, how would a cholesterol denier propose he go on living without this rough blood flow in his arteries? Perhaps ways to eliminate this stress on your coronary arteries would be either to have the heart stop pumping or to drain them of blood. I’m pretty sure if either of those conditions are met, arterial plaque won’t be your biggest problem. It’s a little like saying you need a heart to have heart disease. Yes, you need a heart, and arteries, and you need excess cholesterol. I’m pretty sure only one of those is considered a modifiable risk factor, unless you get a fancy mechanical heart pump like the one former Vice President Cheney has, which does not beat like a heart.
It is true, high blood pressure is an important risk factor for heart disease. Higher blood pressure increases the damage done by high LDL levels. At lower blood pressure, (excess) LDL is less of a problem.
Let’s go back to looking at the process of elimination researchers undertook with other dietary factors. Here’s an excerpt from Gary Taubes’ Good Calories, Bad Calories. Taubes seems to think a promoter of the idea that sugar caused heart disease, John Yudkin, was treated unfairly somehow. He was replaced at the school where he worked by Stewart Truswell, who accepted Ancel Keys’ research on saturated fat. Taubes spins away here, saying that Truswell thought it was more important to encourage the public to eat more onions to avoid thrombosis rather than eat less sugar. It seems clear to me that Taubes is just fabricating a narrative that suits his preconceptions here.
It does seem that onions are anti-thrombotic, so Truswell might have been right about this. However, I haven’t seen evidence that he wanted a publicity campaign for onions, as Taubes suggests.
And Truswell himself makes a strong case against the direct guilt of sugar. It does not raise cholesterol. No one has even considered sugar to be a plausible enough suspect to subject it to a controlled trial. I don’t know, Mr Taubes. It seems your sugar hypothesis is weaker than the lipid hypthesis.
It’s hard to read Taubes’ writing and fail to notice signs of bias. In the quote at the left he seems to believe researchers were caught up in a false choice between saturated fat and sugar as the cause of heart disease. He says it is just assumed that if one hypothesis was right, the other was wrong, and I guess he is saying that is a bad assumption. He says the evidence from epidemiology suggested either sugar or saturated fat could be at fault. But then he switches the focus to what he calls “the potentially deleterious effects of sugar in the diet”. Wait, what about heart disease? Wasn’t that the topic? Does he really think it is in doubt today which is the bigger factor in heart disease? And if he can see that it should not be assumed that this was an either/or choice between sugar and fat, is he willing to entertain the notion that perhaps both might cause heart disease? No, he won’t. Taubes will not concede that saturated fat is at least a part of the problem. He’s the one bogged down in the either/or fallacy.
He tells his readers they should doubt that saturated fat might harm their cardiovascular health, despite all the evidence saying it does. I think Taubes is the one captive to dogma.
As if expressly for the purpose of breaking Gary Taubes free of his false choice between sugar and animal foods as contributors to heart disease, the results of two major epidemiological studies were announced on the same day. Whether or not they cause heart disease, sugary soft drinks were associated with it in men in the study on the left. Red meat, both processed and unprocessed, was associated with increased mortality in the study on the right. Both of these can be true at the same time.
Regarding sugary drinks, individuals who consumed them had elevated triglycerides. Whether or not this is explanatory, it is smart to keep your triglycerides down, and I can offer a good suggestion for that.
In this study, vegans had much lower LDL and triglycerides than omnivores. Mr Taubes, skip the sugar AND skip the meat if you are really interested in avoiding heart disease.
Diets high in sugar did cause atherosclerosis in monkeys in this study, but their diets were also high in saturated fat. This doesn’t contradict the lipid hypothesis.
Now fructose has been investigated as a contributor to heart disease, but again, a study such as this one does not contradict the lipid hypothesis, as the fructose caused an elevation in LDL. Note the subjects here obtained most of their fructose from refined junk food, not from whole food sources.
A more recent review of the effects of fructose put that study in some context. The effects of fructose on LDL seem to be weak. This doesn’t mean refined sugar is healthy. It just doesn’t replace saturated fat as a likely cause of heart disease, regardless of what Gary Taubes says.
Yes, Ancel Keys investigated sugar as a potential cause for heart disease and found the evidence lacking. Yet I don’t see evidence of his refusal to consider the effects of carbs.
Here he set out to determine the effects of various carbohydrates on cholesterol. Even though these did not raise cholesterol, he did not eliminate the possibility that some carbs would. Again, no bias is apparent. This man was a good scientist.
You’ll notice that wheat is one of the foods Ancel Keys investigated for its affect on cholesterol. This one should be understood by all the low carb apologists who want to blame heart disease on wheat. Keys did not have an agenda in his study of the effects of food on cholesterol. He simply tested a variety of foods for their effects on cholesterol and reported the results. It just so happens that saturated fats raise cholesterol and wheat doesn’t. This is the reality, folks. You may as well accept it.
There are so many people online today trying to cobble together a case for wheat’s role in heart disease. The same individuals pushing the myth that Ancel Keys was on a crusade against saturated fat are themselves guilty of stringing together the weakest evidence in their own crusade against wheat. Here, wheat gluten’s ability to bind bile acids is put forth as a way in which it might reduce cancer risk. This should also help to lower cholesterol. This study is based on in vitro experiments.
Here, a diet high in wheat gluten was shown to lower cholesterol in human bodies as well. Wheat gluten is looking good.
Also in humans, this study showed that wheat gluten reduced oxidized LDL and triglycerides, which are the preferred heart disease risk factors of many saturated fat apologists who want you to believe your cholesterol levels are not of concern. Low carbers, shouldn’t you like wheat gluten as a result of this study?
Here, an examination of twenty years-worth of studies showed whole grains and whole wheat bread to have a strong inverse association with heart disease. This is not what you would expect from a food that causes heart disease. The fact that low carbers insist on blaming wheat for heart disease indicates to me that they have never taken an objective look at the evidence out there.
Another dietary factor to receive some attention in the search for the causes of heart disease is lactose. As you know, I’m a vegan. I would have no problem telling you that lactose causes heart disease if it were true. Here, a doctor named Segall sounded alarms over lactose. Yet I have not suggested lactose causes heart disease in my videos. Why not? Am I just a subpar advocate for veganism?
Well, maybe, but that’s not the issue here. I haven’t made this argument because it is not a strong one. The saturated fat in dairy certainly contributes to heart disease, but the lactose probably does not. Segall’s idea has not been supported by the evidence over time. Only a real propagandist would make an argument this weak to serve his agenda.
Someone like Loren Cordain, who continued to cite Segall in his efforts to talk you into quitting dairy. This is how Cordain operates. He has a fad diet to sell. Do you see he references a publication by Segall from 2002?
There it is. It’s about lactose. Lactose probably doesn’t cause heart disease. Dr Cordain, there are plenty of good reasons to cut out the dairy. This is not one of them
Now that I’ve set you up with a solid understanding of the case against saturated fat for it’s contribution to heart disease, I can begin to address my critics. I’ll start with Denise Minger in the next video.