The Drivers of the Herd, Part 20
The NuSI Guys, Part 10, Pick the Charlatan
Slide 3 http://eatingacademy.com/nutrition/the-straight-dope-on-cholesterol-part-i
Dr. Peter Attia says:
“Eating cholesterol has very little impact on the cholesterol levels in your body. This is a fact, not my opinion. Anyone who tells you different is, at best, ignorant of this topic. At worst, they are a deliberate charlatan.”
That’s a fairly clear categorical statement. I’m not ignorant on this topic and it just so happens that I say that dietary cholesterol can have a significant impact on your serum cholesterol levels. I guess that makes me a deliberate charlatan in his view. Now, I’ll admit, I may not be a Very Serious Person like him, but a charlatan? I’ll let you be the judge. That’s not the only question I want you to ponder in this video.
Slide 4 http://eatingacademy.com/nutrition/the-straight-dope-on-cholesterol-part-vii
Dr. Attia also says that a dietary intervention should lower LDL particle count. You’ll recall from the previous video that this is the biomarker that he thinks measures heart disease’s progression best. You might therefore assume that he would only advocate for a diet that is reasonably believed to lower LDL-P.
Slide 5 http://eatingacademy.com/nutrition/how-did-we-come-to-believe-saturated-fat-and-cholesterol-are-bad-for-us
He also thinks that someone who believes that saturated fats and fatty animal foods are bad for the heart would have a hard time justifying that belief. Therefore, he must believe that saturated fats and dietary cholesterol don’t raise LDL particle number or apoB. I think that at best, he is ignorant of this topic. The second question you should answer for yourself as you watch this video is, is Dr. Peter Attia sincerely trying to help you? I’ll use the rest of this video to show you that dietary cholesterol does raise the blood cholesterol of healthy individuals and I’ll show you that the foods he defends are a disaster for apoB. You can form your conclusions accordingly.
Slide 6 http://eatingacademy.com/nutrition/the-straight-dope-on-cholesterol-part-vi
Please remember this quote of his as we proceed. Dr. Attia says, “The primary driver of atherosclerosis is the number of apoB trafficking lipoproteins in circulation.” We’re going to be seeing a lot more about apoB in this video. If we see that something increases apoB, we should infer from Attia’s statement that that food increases the primary driver of atherosclerosis. We might therefore expect that Attia, if he were dealing in good faith, would have a special level of concern about that food.
Slide 7 Sacks, Frank M, et al. "Ingestion of egg raises plasma low density lipoproteins in free-living subjects." The Lancet 323.8378 (1984): 647-649.
Study number one. Here we avoid a common problem of study design in dietary cholesterol trials. The subjects in this one didn’t start with high cholesterol. This makes it easier for us to see what dietary cholesterol really does to healthy people. The subjects were young, healthy lactovegetarians. Their average cholesterol level at the start of this was 175 mg/dL. They consumed just one large egg per day on top of their usual diets. The trial was a double-blind crossover design. Adding just one egg daily raised LDL cholesterol by 12% in three weeks. ApoB went up 9%. Since eggs raise apoB, Peter Attia should be opposed to eating eggs.
Slide 8 Eggs are used in these studies because they are such a concentrated source of dietary cholesterol. Every time I mention eggs in this video you should think “dietary cholesterol.” There you see the changes. Is 12% in three weeks “very little impact,” as Attia says. I don’t think so.
Slide 9 Neither did these researchers. They said the increase in LDL was “significant.”
Slide 10 Beynen, Anton C., and Martijn B. Katan. "Effect of egg yolk feeding on the concentration and composition of serum lipoproteins in man." Atherosclerosis54.2 (1985): 157-166.
Number 2. In this one we again start – quite appropriately – with healthy people. Also appropriate was the introductory low-cholesterol diet before they added the cholesterol. After 10 days of eating six egg yolks per day their LDL cholesterol shot up 21%. Again, that seems rather significant to me.
Slide 11 Packard, Christopher J., et al. "Cholesterol feeding increases low density lipoprotein synthesis." Journal of Clinical Investigation 72.1 (1983): 45.
Study 3. This study added six eggs per day, too. There you see what that did to apoB levels. That’s about a 40% increase. Why would someone who says apoB should be low not be against eating eggs?
Slide 12 Schonfeld, Gustav, et al. "Effects of dietary cholesterol and fatty acids on plasma lipoproteins." Journal of Clinical Investigation 69.5 (1982): 1072.
Study 4. In this study you can see graphically what happened as three and then six eggs were added to the diets of healthy young men. It looks to me like their LDL cholesterol went way up on the eggs and dropped right back down again when the eggs went away. When there were fewer polyunsaturated fats in their diets the effects were especially pronounced. The 3-egg period was four to five weeks, the 6-egg period was 4-6 weeks, and the egg withdrawal period was three weeks.
Slide 13 There you see the authors wrote, “ApoB increased significantly when cholesterol was added” to the basal diets. Notice who one of those authors was. Robert Olsen’s name will be familiar to you if you saw my second video in this playlist. Why was he such an opponent of recommendations to reduce cholesterol in the diet even after he took part in this study? Watch that video again and you might be able to think of a reason why.
Slide 14 Ginsberg, Henry N., et al. "A dose-response study of the effects of dietary cholesterol on fasting and postprandial lipid and lipoprotein metabolism in healthy young men." Arteriosclerosis, Thrombosis, and Vascular Biology 14.4 (1994): 576-586.
Here’s another study, study number 5, showing what dietary cholesterol does to apoB. This study used participants whose baseline LDL was 100 mg/dL.
Slide 15 von Birgelen, Clemens, et al. "Relation between progression and regression of atherosclerotic left main coronary artery disease and serum cholesterol levels as assessed with serial long-term (≥ 12 months) follow-up intravascular ultrasound." Circulation 108.22 (2003): 2757-2762.
Remember, it appears that in order for plaques to stop worsening LDL cholesterol needs to be around 75.
Slide 16 Ginsberg, Henry N., et al. "A dose-response study of the effects of dietary cholesterol on fasting and postprandial lipid and lipoprotein metabolism in healthy young men." Arteriosclerosis, Thrombosis, and Vascular Biology 14.4 (1994): 576-586.
The researchers here found that dietary cholesterol raised apoB by 10% in eight weeks.
Slide 17 Knopp, Robert H., et al. "Effects of insulin resistance and obesity on lipoproteins and sensitivity to egg feeding." Arteriosclerosis, thrombosis, and vascular biology 23.8 (2003): 1437-1443.
Study 6. You may wonder why I keep mentioning when a study used healthy young people. You can learn from this study why it matters. Participants were placed into three categories: insulin-sensitive, insulin-resistant, or obese insulin-resistant. They also started with different LDL cholesterol concentrations. As you can see at the bottom, the average LDL was generally too high, although the insulin-resistant groups were in especially bad shape.
Slide 18 Knopp, Robert H., et al. "Effects of insulin resistance and obesity on lipoproteins and sensitivity to egg feeding." Arteriosclerosis, thrombosis, and vascular biology 23.8 (2003): 1437-1443.
Despite that, you can see that eating four eggs per day for four weeks raised LDL in every group. Those are percentage values in the middle of your screen. Sure, you can say in this case that the effect of dietary cholesterol on the two insulin-resistant groups was trivial. But some of us are in better health than that and want to stay that way.
Slide 19 Knopp, Robert H., et al. "Effects of insulin resistance and obesity on lipoproteins and sensitivity to egg feeding." Arteriosclerosis, thrombosis, and vascular biology 23.8 (2003): 1437-1443.
There you see that in the insulin-sensitive participants all that cholesterol caused a 9.5% increase in their apoB. Dr. Attia says apoB is the primary driver of atherosclerosis.
Slide 20 Zanni, E. E., et al. "Effect of egg cholesterol and dietary fats on plasma lipids, lipoproteins, and apoproteins of normal women consuming natural diets."Journal of lipid research 28.5 (1987): 518-527.
We’re now up to study number 7. In this one nine women with good total cholesterol numbers consumed different combinations of fats and cholesterol for 15 days. The first diet used corn oil as its fat and contained 130 mg of cholesterol. This resulted in the lowest cholesterol numbers. Serum cholesterol went up from there in all the other diets they tested. One diet used corn oil again but added 875 mg of cholesterol. Another that used lard as the fat with 130 mg of cholesterol. The last diet used lard plus 875 mg of cholesterol. The authors called each increase, whether from dietary cholesterol or lard or both, “significant.”
Slide 21 Dr. Attia should note that each of those three diets increased LDL particle count. Lard plus high cholesterol increased particle count by 18% in 15 days.
Slide 22 Vuoristo, Matti, and Tatu A. Miettinen. "Absorption, metabolism, and serum concentrations of cholesterol in vegetarians: effects of cholesterol feeding."The American journal of clinical nutrition 59, no. 6 (1994): 1325-1331.
Number 8. In this study the subjects were healthy vegetarians who normally consumed dairy and eggs. They added cholesterol to their diets in the form of three eggs per day for two months.
Slide 23 Notice the LDL line in particular here. Their LDL went up 20% in that amount of time. That is a major increase, especially considering they started with LDL around 117 mg/dL.
Slide 24 Here again, the authors found the effect of cholesterol feeding to be significant. The people who tell you that dietary cholesterol doesn’t affect blood cholesterol usually will say that the liver just produces less cholesterol to compensate for what you ate but you can see that that is not what happened here. “There was no lowering of cholesterol synthesis,” these researchers wrote.
Slide 25 McMurry, Martha P., William E. Connor, and Maria T. Cerqueira. "Dietary cholesterol and the plasma lipids and lipoproteins in the Tarahumara Indians: a people habituated to a low cholesterol diet after weaning." The American Journal of Clinical Nutrition 35.4 (1982): 741-744.
Study number 9 is especially interesting. Here the subjects were Tarahumara Indian men. That’s the tribe that is legendary for their long distance running prowess. Their diets were traditionally high in complex carbohydrates. These men were healthy and young. They began this study with a very low, very healthy total cholesterol measurement of 120 mg/dL. Excluding dietary cholesterol from their diets for three weeks lowered that still further to 113. Then 900 mg of cholesterol was added to their diets for three weeks. 900 mg of cholesterol is about how much you’d get in three and a half eggs. This caused their cholesterol to shoot up to 147, about a 30% increase. Their LDL cholesterol went up about 30% as well.
Slide 26 Connor, William E., Daniel B. Stone, and Robert E. Hodges. "The interrelated effects of dietary cholesterol and fat upon human serum lipid levels." Journal of Clinical Investigation 43.8 (1964): 1691.
Study 10. In this study from 1964 subjects started with a high-cholesterol diet and then were switched to a cholesterol-free diet.
Slide 27 After four weeks their cholesterol numbers fell almost 40 points. Once again, we see that dietary cholesterol can affect your blood cholesterol quite dramatically.
Slide 28 The researchers said their findings emphasized the important influence of dietary cholesterol upon serum lipids. Were they charlatans, too?
Slide 29 Connor, William E., Robert E. Hodges, and Roberta E. Bleiler. "The serum lipids in men receiving high cholesterol and cholesterol-free diets." Journal of Clinical Investigation 40.5 (1961): 894.
Study number 11. Two of the same researchers ran this study a few years earlier. The graph very clearly illustrates what happened. You can see the number of weeks spent on each diet along the bottom. Each of those lines corresponds to a different person. They were fed differing amounts of cholesterol, from 475 mg to 1425 mg. They all responded a little differently but they all responded. Dr. Peter Attia says that it is a fact, not an opinion of his, that dietary cholesterol has very little influence on serum cholesterol. Is that what you see in this graph? Do you think this data comes from the opinions of these researchers?
Slide 30 Lehtimäki, Terho, et al. "Cholesterol-rich diet induced changes in plasma lipids in relation to apolipoprotein E phenotype in healthy students." Annals of medicine 24.1 (1992): 61-66.
Here’s our twelfth study. This time participants consumed three eggs per day for three weeks after an egg-free run-in period. The researchers stated that those eggs “induced significant increases in total cholesterol, LDL cholesterol, and apoB.” Again, we have to wonder why Dr. Attia is encouraging people to consume foods that raise apoB. He says higher atherogenic particle concentrations are what drive heart disease. How can he not know this?
Slide 31 There you see apoB going up and down as eggs were added and then taken away.
Slide 32 Boerwinkle, E., et al. "Role of apolipoprotein E and B gene variation in determining response of lipid, lipoprotein, and apolipoprotein levels to increased dietary cholesterol." American journal of human genetics 49.6 (1991): 1145.
Here is number 13. This compared a high-cholesterol diet with an extremely high-cholesterol diet. You can see below what three weeks on each diet did to their LDL and apoB. The authors said that the higher-cholesterol diet “significantly increased” LDL and apoB.
Slide 33 Turner, JOHN D., N. A. Le, and W. VIRGIL Brown. "Effect of changing dietary fat saturation on low-density lipoprotein metabolism in man." American Journal of Physiology-Endocrinology And Metabolism 241.1 (1981): E57-E63.
Let’s talk about saturated fat now rather than dietary cholesterol. For our 14th study, subjects were given diets with identical macronutrient ratios for 7 to 9 weeks. The major difference between the diets was that one used safflower oil as its fat source and the other used lard. They had two categories of subjects, those with normal LDL levels and those with high LDL levels. I would say the groups would be better described as having high and extremely high LDL. One group had LDL levels averaging 117. The other group averaged 329, which is totally nuts. The lard raised apoB for every single person in this study. It was found that its high saturated fat load both increased the production of LDL and reduced the fractional catabolic rate of LDL. There’s only one thing that you can say about a food that is that hard on your heart.
Slide 34 http://eatingacademy.com/dr-peter-attia
Praise the lard! Right, Dr. Attia?
Slide 35 Vessby, Bengt, et al. "Reduction of high density lipoprotein cholesterol and apolipoprotein AI concentrations by a lipid-lowering diet." Atherosclerosis 35.1 (1980): 21-27.
In number 15 people in Sweden with high cholesterol were studied. This wasn’t a great study but I included it here for your interest anyway. The main problem with this one was that we don’t know what the usual diets of these people had been. They were given a diet that, when compared to the average Swedish diet, was lower in fat, and that fat had a higher ratio of polyunsaturated fats to saturated fats.
Slide 36 The effect was a 27% reduction in apoB over four weeks.
Slide 37 Cooper, Richard S., et al. "The selective lipid-lowering effect of vegetarianism on low density lipoproteins in a cross-over experiment." Atherosclerosis 44.3 (1982): 293-305.
Number 16. In this study, subjects were placed on a vegetarian diet, with skim milk as the only animal product they were allowed. In three weeks, this diet dropped LDL by almost 15% and apoB by 13%. If a reduction in dietary cholesterol and saturated fat reduces apoB, why doesn’t Dr. Peter Attia use NuSI to explore that approach?
Slide 38 I must point out that this was an especially worthwhile study because its subjects were not typical in that they were young and healthy and were not consuming a fatty, sugary diet prior to the study.
Slide 39 The participants also didn’t come into this with high cholesterol, as you usually see. Nevertheless, their cholesterol fell on the new diet by almost 20 points.
Slide 40 Some of that was no doubt attributable to the vegetarian dieters spontaneously reducing their caloric intake. Neither diet represented something Peter Attia or I would especially like. But you can see that carbs as a percentage of calories were higher and saturated fat intake was much lower while eating this diet than is the norm.
Slide 41 And this resulted in a clear lowering of Apo-B. As I said, the vegetarian diet provided a 13% advantage with respect to apoB.
Slide 42 The dietary intervention wasn’t ideal in part because they were trying to address a different question. Their concern was over the drop in HDL usually seen when people switch to low-fat diets.
Slide 43 Kent et al.: “The effect of a low-fat, plant-based lifestyle intervention (CHIP) on serum HDL levels and the implications for metabolic syndrome status – a cohort study.” Nutrition & Metabolism 2013 10:58.
That is not a worry we should have today about vegetarian diets. We know now that HDL levels needn’t be the focus of concern among people eating low-fat and plant-based.
Slide 44 Cortese, C., et al. "Modes of action of lipid‐lowering diets in man: studies of apolipoprotein B kinetics in relation to fat consumption and dietary fatty acid composition." European journal of clinical investigation 13.1 (1983): 79-85.
Paper number 18 is a two-for-one deal. It reported on two experiments the authors conducted. This was an especially interesting article that helps to explain why we see these differing effects of fats. Each experiment lasted three weeks.
Slide 45 The first study compared different levels of fat in the diet, 45% versus 25%, with the fat quality the same for both. Total calories were the same.
Slide 46 The authors wrote, “on the LF diet all subjects had a lower pool size of LDL apo B, the mean reduction being 30%.” During the low-fat diet, not only was less apoB being produced in these people, more was being broken down.
Slide 47 In the second experiment they kept both diets relatively high in fat. This time the effects of different fats were observed. The two fats they compared were butter fat and sunflower oil. Bear in mind that sunflower oil’s omega 6 to omega 3 ratio is approximately 130. The conventional wisdom of the blogosphere would lead you to believe that such an oil should have seriously harmed these people.
Slide 48 But what actually happened was lower triglycerides, lower LDL cholesterol, and lower apoB. Butter fat was worse than sunflower oil by all these metrics.
Slide 49 Nestel, Paul J., Timothy Billington, and Brian Smith. "Low density and high density lipoprotein kinetics and sterol balance in vegetarians." Metabolism30.10 (1981): 941-945.
In study number 19, vegetarian Seventh Day Adventists were compared to matched non-vegetarians. The vegetarians normally consumed eggs and dairy but for this study they agreed to go one month with no eggs and only low-fat dairy. The non-vegetarians were healthy and matched for age and weight. You can see that the vegetarians had much lower apoB levels. Anyone who wants to see us avoid heart disease by reducing our atherogenic particles needs to consider recommending vegetarianism.
Slide 50 Jebb, Susan A., et al. "Effect of changing the amount and type of fat and carbohydrate on insulin sensitivity and cardiovascular risk: the RISCK (Reading, Imperial, Surrey, Cambridge, and Kings) trial." The American journal of clinical nutrition 92.4 (2010): 748-758.
Last is number 20. This is the study that low-carbers love to cite as evidence that saturated fat doesn’t harm insulin [sensitivity]. They forget that it demonstrated that saturated fat increases apoB, whereas a low-fat diet decreases it.
Slide 51 http://eatingacademy.com/nutrition/the-straight-dope-on-cholesterol-part-i
Now that you’ve seen all those studies, you can adopt an informed opinion about who is a deliberate charlatan and who is actually trying to help you.
With all the evidence against saturated fat and cholesterol that I’ve shown you in these videos, you may be wondering why the public is being bombarded with messages that say that they are good for you. Why, for example, does a physician like Peter Attia say the things he does? I’m not sure I can answer that question. But maybe you’ll come up with an explanation of your own after you watch the next video.