Chris Kresser is awful. Part 1. Saturated fat and dietary cholesterol DO raise blood cholesterol levels. - The Diet Wars (2023)

Chris Kresser, a frequent guest on the Joe Rogan Experience, is awful. This post will explain why.

Kresser is not science-based. He spreads misinformation about health and nutrition science. I cannot detail why all of this misinformation is misinformation because it would take many hours, and I have many other things to do.

I can however explain at significant depth why he is wrong about one particular fact. In doing so, I hope that readers will take away how unreliable he has been about this one particular issue. And I hope that this will cause them to be a little more cautious about everything else that they read from him.

Some may argue that everyone is wrong about some things. This might be true, but this argument does not apply to Chris Kresser. Chris Kresser systematically rejects science, opting to instead promote ideas wildly at odds with the evidence and conspiracy theories to explain why he is right and scientists are wrong. He often purports that modern medicine is out of step with the current science and that he is on the cutting edge. (This is false. In fact, Kresser merely riffs off of popular science books that have claimed the same and is himself often not familiar with the actual scientific literature.)

I cannot emphasize how much Chris Kresser is, in a word, systematically wrong. But perhaps the following post can be a lesson. I have titled this “Part 1” in case I need to make more of these posts to convince others and actually have enough energy to keep doing so. Most likely, I will not, but it is always possible.

Without further ado, Chris Kresser ladies and gentlemen…

Kresser has an incredibly slick and very aesthetic website. As you can see next to the title, his articles are even “Fact Checked”.

“Fact Checked”! What does that even mean?

From the website:

In other words, people on Kresser’s staff, whose salaries he pays and who are not financially independent of him and his extreme views (as we shall see in a moment), must fact check Kresser.

Anyone got any guesses about just how impartial these “fact checkers” who are fact-checking their boss are likely to be? My guess: anywhere from “not very” to “not at all”.

Kresser opens by citing the World Health Organization and pointing out according to recent studies that cardiovascular disease is largely preventable.

True, but what is the largest risk factor according to this study?

“Raised apoB/apoA1 ratio.” Hmm, what is apoB?

As we see from a seminal 2016 article published by the European Atherosclerosis Society Consensus Panel:

ApoB, short for apolipoprotein B, is the constituent lipoprotein on LDL particles.

What does that mean? This is not a primer on blood lipids, but it basically means this: in order to dissolve in the blood, cholesterol needs a protein carrier. This protein carrier dissolves in the blood. The protein carrier for LDL cholesterol is called apolipoproteinB, or apoB. There is one apoB per LDL molecule.

So, remember, the apoB/apoA1 ratio is the ratio of the protein carrier for LDL to the ratio of… wait, what’s apoA1? Easy peasy. ApoA1 is the lipoprotein carrier for HDL.

Remember that lipid panel you got? LDL and HDL are the major components. Well, this is them.

In other words, the ratio of apoB to apoA1 is roughly equivalent to the ratio of LDL to HDL. So what this paper is saying is that the ratio of LDL to HDL is the most important risk factor for cardiovascular disease.

Let’s jump forward.

Here Kresser claims that he is going to “debunk 3 common myths about heart disease.” One of these myths is that high cholesterol in the blood is the cause of heart disease.

But wait a moment. Isn’t a high ratio of LDL/HDL a risk factor for heart disease?

Let’s keep that question in mind as we move forward.

Here Kresser claims that the medical establishment is still diagnosing and treating heart disease according to science that is 40-50 years old. Interesting, because my cardiologist friends seem to be constantly updating their techniques and approaches to cardiovascular disease. Also: I didn’t know that Chris Kresser is a cardiologist!

Perhaps more interesting is this:

“More recent (and higher quality) evidence doesn’t support it.”

Oh really?

Here’s Kresser’s next paragraph:

Clicking on his reference, we see the following:

In other words, on average eggs do not increase the LDL to HDL ratio, which as we saw above in Kresser’s first reference was one of the best predictors of cardiovascular disease risk.

But then…

We see that in hyperresponders, or 25% of the population, this ratio probably is increased: LDL goes up faster than HDL.

Let’s check out the final two paragraphs of this paper. Read the highlighted portions carefully.

First, here:

In other words, up to one-third of the population (people with type 2 diabetes are about 10% of the population) may be susceptible to atherosclerosis (diabetics, as mentioned earlier in the paper, not shown in this blog post) or to a worsening of the LDL/HDL ratio upon consuming dietary cholesterol.

In other words, things are a lot less clear than Kresser lets on.

This, coming from the very article that he is citing in favor of a dogmatic view that dietary cholesterol is unimportant.

That is not what the article that he is citing says.

To put the icing in the cake, the final sentence comments on current recommendations on dietary cholesterol:

Why? Since a large proportion of the population might respond negatively to intake of dietary cholesterol, the paper suggests that dietary cholesterol might best be minimized.

In other words, the article that Chris Kresser cited to show that dietary cholesterol “does not increase the risk of heart disease”? It recommends to minimize intake of dietary cholesterol.

I do not mention this to argue that dietary cholesterol necessarily should be restricted. I only point this out because it makes clear that Kresser is selectively reading the scientific literature in order to make a biased and partisan case for one point of view, while the very literature he cites makes both a more nuanced case and gives the exact opposite recommendation.

What about saturated fat? Kresser writes:

Let’s take a look at the reference, shall we?

Ah, Mensink and Katan’s classic meta-analysis of 60 trials. “Some studies,” Kresser wrote. “Some?”

Still, it’s an old meta-analysis. A more recent one was published in 2016, with Mensink as the sole author, commission by the World Health Organization:

Clocking in at 72 pages, this report contains everything one would want to know about fatty acid replacement, including 91 studies:

“Some studies.”

Let’s revisit that statement again.

“These studies are almost always short-term, lasting only a few weeks.”

Really?

Here is a sampling of one page of the list of 91 studies that Mensink used in his analysis:

84 days, 42 days, 49 days. And that’s just among 10 studies. Some of these studies lasted over 90 days. And many lasted over 50. “Lasting only a few weeks”?

Yeah. OK. Sure.

Here is a characteristic table from the study, showing a powerful relationship between the replacement of saturated fat with other macronutrients on blood cholesterol levels:

In other words, robust changes in blood lipid markers in response to replacement of saturated fat by other macronutrients.

But fine, let’s ignore those studies. What about Chris’s other studies?

Apparently all of those other studies show that cholesterol levels don’t go up with saturated fat?

The reference cited is an article from Stephan Guyenet’s blog.

In it, Stephan makes the case that the observational studies show little relationship between saturated fat and blood cholesterol.

But hey, wait a second…

Observational studies? In other words, nutritional epidemiology? Chris Kresser is now using nutritional epidemiology to demonstrate that there is no relationship between saturated fat intake and blood cholesterol?

But wait- I thought- I thought Chris Kresser thinks nutritional epidemiology is worthless.

Here is what Chris Kresser says about nutritional epidemiology:

I quote: “Pseudoscientific”.

And he uses the entire post to take cannon ball shots at nutritional epidemiology from every angle in like fashion, with quotes such as:

And with sections such as this:

In other words, Chris Kresser lambasts nutritional epidemiology. UNLESS… UNLESS… well, unless it shows that there is no relationship between saturated fat intake and blood cholesterol.

Well, why the fuck not! If nutritional epidemiology shows it, it’s probably true! Nutritional epidemiology is proof that there is no relationship between saturated fat intake and blood cholesterol, even when the randomized controlled trial literature shows a strong relationship.

BUT… nutritional epidemiology is wrong about everything else.

Right Chris Kresser?

Still, if I were playing Devil’s advocate, I would say that, well, Chris could shoot back:

“Yeah sure nitpicker Bass. Blood cholesterol responds in the short-term RCTs. Yeah, and maybe I misspelled “months” as “weeks”. But the point is, how do we know over a long period of time that blood cholesterol declines in response to lower saturated fat intakes? It might be a temporary effect rather than a long-term effect. The long-term data we have shows that, on the order of years, there is no effect of saturated fat intake on blood cholesterol. It might be observational, but it is the only data we have. So at minimum, even though I have repeatedly argued that epidemiological data are trash, we have to accept that blood cholesterol might not be reduced by reducing saturated fat.

QED”

Maybe Chris is right. Maybe we don’t know if there is any effect of reducing saturated fat on blood cholesterol…

If we were living in the 1960s.

Because two very famous studies that sought to test the diet-heart hypothesis (as he calls it) did, in fact, study this very question: could reduction of saturated fat over the course of years cause reduced blood cholesterol levels?

The first in Circulation, an official journal of the American Heart Association:

And it found:

Oh shi-

Here are the methods. Basically, 40% of calories in fat were replaced in the normal diet by unsaturated fat:

Chris Kresser, ladies and gentleman:

But wait, there’s more!

The Oslo Diet-Heart Study, also published in Circulation, this time in 1970:

What happened to the cholesterol?

Yep, it went down.

Here are the methods (from the 1968 version):

So what is it Chris? Do we believe the randomized controlled trial literature of hundreds of studies, verified by at least two long-term trials?

Or the observational epidemiology?

Another question: why is it that Chris forgot about these incredibly famous studies when reporting the role that unsaturated fat plays on blood cholesterol?

Then Chris Kresser decides that a 6-foot grave isn’t deep enough and wants to go even deeper. So, he talks about low-carbohydrate diets:

What a coincidence! A new, comprehensive, 24-page report on low-carbohydrate diets, including every study and meta-analysis on the various effects discussed was recently published by the National Lipid Association in the Journal of Clinical Lipidology:

To be sure, the National Lipid Association is one of the most respected lipids organizations in the world. And researchers from many of the world’s most prominent universities are on the authors list.

And here is what it found on the effects of low-carbohydrate diets on blood lipids:

“A high saturated fatty acid (SFA) content in low-CHO and very-low-CHO diets is a key factor for an increase in LDL-C.”

In other words, while low-carbohydrate diets higher in mono- and polyunsaturated fats caused lower total and LDL cholesterol, diets higher in saturated fats caused higher total and LDL cholesterol.

And here’s the thing. Kresser could have known that when he wrote this published this article June 11, 2019. There were dozens of papers showing increased LDL cholesterol levels in response to low-carbohydrate diets and a dozens of reviews and meta-analyses that point out that the fatty acid composition is critical in determining the response of LDL cholesterol to these diets.

But did Kresser talk about that at all? Nope.

If he had talked about it, he could have helped people who had high blood cholesterol to keep it lower. Ah, but yes, according to him, blood cholesterol is not important for cardiovascular disease, so he doesn’t need to help his readers prevent increased blood cholesterol levels.

Which brings up an interesting point: why is it important for him to argue that dietary cholesterol and saturated fat don’t increase blood cholesterol if blood cholesterol does not cause heart disease?

My guess: Chris is defending his turf at every point possible as someone who recommends high meat intake and “natural” remedies. It is straight from the denialist’s playbook: make the chain of denial so long, impenetrable, and ridiculous that nobody wants to even bother challenging it.

Oh, but let’s continue:

I can’t even.

He is literally saying that a diet high in saturated fat will cause a decrease in blood cholesterol in half of the people to whom it is fed. This is not supported by a single study out of hundreds, and is totally invented by Chris Kresser.

It’s as if even with his throwaway paragraphs, he wants another opportunity to make things up.

Let us continue.

Ancel Keys claiming that the diet-heart hypothesis is dead? Let’s actually look at the original article.

First let us note that Chris Kresser leaves out the first and last sentences, only quoting the middle to make his point. Let’s take a closer look at these sentences.

The first argues that blood cholesterol is important and that thinking otherwise will cause confusion among the public:

The last sentence points out that fatty acids are important (meaning saturated fats):

In fact, this was a restatement of the positions that he had maintained since the 1950s: Ancel Keys early pointed out that dietary cholesterol had only a modest effect on blood cholesterol levels, while he demonstrated through the Seven Countries Study and subsequent work that saturated fats played a decisive role in cardiovascular disease. Which is exactly what he says again in this letter to the editor.

Yet Chris wants to use this letter to imply that Keys had reversed his position:

It is a total distortion of the facts. Kresser literally took a quotation out of context to make the author look as if he believed the opposite of what he really believed.

Are we seeing a pattern here? However Chris Kresser can land a shot, he does. He denies that saturated fat raises cholesterol. He denies that cholesterol causes heart disease. He denies that saturated fat causes heart disease. He denies that statins prevent heart disease. He distorts the clinical trial evidence and mischaracterizes it. He cites only epidemiological studies, while in other articles calling epidemiology pseudoscience. He ignores any mention of RCT data that would definitively repudiate his claim. He cherrypicks meta-analyses and declines to provide context. He tries to make it look like Ancel Keys reversed his position.

And no matter what claim he needs to defeat, he can always come up with some way of cherrypicking evidence or quotations or ignoring to make it appear defeated. It is one of the most flagrantly dishonest styles of scientific argumentation that I have read in my life.

We’re not done yet.

In a Research Spotlight, Kresser suddenly reverses his position completely and affirms the pivotal importance of LDL cholesterol for cardiovascular disease:

You couldn’t make this up if you tried. It is one of the most flagrantly ridiculous endings to a ridiculous article that I have read in my life.

Oh it gets worse. You didn’t think it could. But it does.

He continues, describing a recently published study that demonstrated how to reduce blood cholesterol through lifestyle. There were three groups:

And according to Chris, they saw a modest decline in LDL cholesterol:

What did the group interventions consist of? I looked up the methods paper. And I have highlighted the relevant portion:

Yep. That’s right. Saturated fat restriction. In both groups that saw an improvement in LDL cholesterol, there was saturated fat restriction.

Chris concludes, praising the intervention:

And with that, the conclusion:

All of that text. All of that work. Just to show that how dishonestly/incompetently Chris Kresser wrote a single short article. Kresser writes hundreds of articles. A substantial proportion are total BS just like this one, argued using an identical ad hoc, cherrypicking methodology that focuses on proving the point rather than being objective.

But how is it possible to know which ones are good and which are nonsense? Here’s a tip: I recommend not reading anything he writes.

And now I am off to hang myself with my shoelaces.

This world. Too much for me.