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Latest Meat Scare: ‘Shocking Ignorance’

Latest Meat Scare: ‘Shocking Ignorance’
Angelo Coppola

The meat-will-kill-you brigade was out in full force last week. This time, the media frenzy and exaggerated headlines were the result of research being published in the journal Nature Medicine.

The article is called, Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis.

Translation: When gut bacteria process L-carnitine, which is found in red meat, it leads to hardening of the arteries.

Based on that title and the claims made in the article, perhaps extreme headlines are justified?

Well, let’s take a look at the headlines, the basic premise, and how some thought leaders have interpreted the research. Hopefully, this article will provide you with some insights and the proper starting point for you to continue to looking into the issue if you wish. Even if the Internet is robbing you of our ability to focus, it’s worth following along just to cut through this round of BS and in order to better recognize the next round, which is sure to come.

The Headlines

Before we commence, the proper music is in order. Let’s set the stage, shall we? Hit play.

Here’s how the media grabs the eyeballs and clicks that they so desperately need.

Want some more? OK, as long as those headlines haven’t raised your stress levels and blood pressure too high, there are plenty more to go around:

Sadly, I could go on, but let’s call it done. Clearly, red meat is going to kill you and you shouldn’t be eating it, because now scientists finally KNOW WHY it is KILLING you. They’ve certainly been looking for a reason long enough.

The Simple Version

Here’s the basic story:

Meat contains a compound called carnitine. When we eat meat, the bacteria in our digestive system processes the carnitine and generates another compound called trimethylamine (TMA). The liver then converts the TMA into trimethylamine n-oxide (TMAO). The current research claims that higher blood levels of TMAO will lead to atherosclerosis.

Simple right? Either it does or it doesn’t.

Well, no. And when you take a look at the research methods, the confounders, the potential conflict of interest, and other factors that stack up against this conclusion, you begin to see that it’s anything but simple. Not only that, the researchers’ conclusions seem far from likely.

The Rest of the Story

And now, let’s take a look at how Anthony Colpo, Paul Jaminet, Chris Masterjohn, and Mark Sisson have approached this research.

Anthony Colpo

Anthony Colpo provides an entertaining, yet thorough and scientific, tear-down of the study. If you’re going to read about TMAOs and carnitine, you may as well have a good time and start with Bullshit Study of the Year: “Carnitine Causes Heart Disease”.

Colpo minces no words and tells us plainly:

  • Carnitine does NOT cause heart disease.
  • No-one — I repeat NO-ONE — has ever shown red meat nor supplemental carnitine to cause heart disease in human beings. Not the ‘researchers’ responsible for the appalling Nature Medicine paper, and not anyone else.

"Write a good press release, and you can be assured the shocking ignorance of most health reporters and the public’s eternal gullibility and faith in authority will do the rest." — Anthony Colpo

Other salient points include:

So what we have is a study which used misrepresented epidemiology, blatant cherry-picking and a singles bar attitude to metabolomics as a springboard to validate what strongly looks like a preconceived agenda to implicate red meat and carnitine in the pathogenesis of heart disease.

Colpo also points to Spanish, Egyptian and Italian research that the study in question here apparently ignores. They show potential improvements related to cardiovascular deaths, heart rhythm, reduction of angina attacks, blood pressure, and even erectile dysfunction.

Check out the article for a look at the competing financial interestes of the research authors as well as the rest of the general awesomeness therein contained.

Paul Jaminet

In Paul Jaminet’s Lessons from the Latest Red Meat Scare, he quickly informs us that the same group behind the current study was behind a similar study just a couple of years ago. In their previous study, phosphatidylcholine was shown to be metabolized by gut flora, which then lead to TMAO production in the liver. Sounds familiar, right? And, phosphatidylcholine (or PC or lecithin) is found in eggs, milk, liver, red meat, poultry, shell fish and fish.

This doesn’t inherently invalidate their current research, but it’s interesting to know that they’ve been on the TMAO case for quite some time.

None of these lessons is new. This study doesn’t overturn any established dietary wisdom. It is just one more piece of data reminding us to eat a balanced diet consisting of the foods we evolved eating – plant as well as animal.

In the remainder of Jaminet’s assessment, we learn:

  • His book asserts that high protein intake is suboptimal for gut health
  • Gut bacteria can ferment protein, which generates toxic compounds
  • He boils down gist of the new research to: “fermentation of meat in the gut produces TMA leading to TMAO production which may increase your chance of atherosclerosis by 11%”
  • The risk is highly dependent on the nature of an individual’s gut flora
  • A low fiber diet could lead to starving the “good” bacteria and feeding the “bad” bacteria that produce TMA
  • TMAO in blood only becomes atherosclerotic in the context of metabolic syndrome brought on by endotoxemia
  • A high-sugar, high-flour, low-fiber diet provides the necessary landscape for endotoxemia
  • Fiber and resistant starches from in-ground starches (like potatoes) are protective
  • Eating excessive meat provides more protein for potential fermentation, which then can produce harmful byproduct

Paul’s full article is here.

Chris Masterjohn

Chris Masterjohn writes the Mother Nature Obeyed blog, which is hosted by the Weston A. Price Foundation. He tackled this story in an article called:

Does Carnitine From Red Meat Contribute to Heart Disease Through Intestinal Bacterial Metabolism to TMAO?

If you are not familiar with Chris’ work, he is well known with regards to his work on cholesterol.

The problems with this study and its portrayal in the media are the often- times incomplete reporting of data in the paper and the wild runaway inferences published all over the press[.] - Chris Masterjohn
In Chris’ article we learn:

  • 8 oz. of carnitine-rich foods, like meat, produce no more TMAO than fruits and vegetables, while seafood produces significantly more
  • In other studies, beef and other foods, did not produce significantly more urinary secretion of TMA + TMAO than a control meal
    • Fruits and vegetables produced similar results to beef (red meat)
    • Chicken and other meats produced similar results to beef (red meat)
    • Several foods produced higher values than beef (like mushrooms, peas, eggs, and seafood), so why pick on red meat?
  • There could potentially be gender differences in TMAO production
  • The post-meal increases in TMAO levels, relative to the total TMAO pool, appear to be insignificant
  • It is unknown whether any outliers in the research group drastically altered the average results
  • Female C56BL/6J mice genetically engineered to be missing ApoE, an important protein involved in lipoprotein metabolism, developed twice as much atherosclerosis when fed a thousand steaks a day worth of carnitine.
  • If carnitine conversion to TMAO causes atheroscelrosis, then seafood ought to be considered the main culprit — yet Kitavans, an island people who eat seafood plentifully, are virtually free of heart disease.

Mark Sisson

In Does Red Meat Clog Your Arteries After All, Mark Sisson provides an easily understood interpretation of the data and offers advice that is equally easily digested, even by those without advanced degrees in biochemistry.

This is probably the article you want to forward along to your Aunt Thelma or Uncle Jack who is worried about your caveman diet, since the others require a bit more geekiness to grok…so to speak.

Eat a variety of foods. Don’t just eat steak. Eat fish, and eggs, and chicken liver, and pork chops. Don’t just eat meat. Eat vegetables. Eat probiotic-rich foods. Eat prebiotic-rich foods...[P]rovide food for your gut and diversify the population. — Mark Sisson

Other articles

You can find more about this topic in these articles:

Humans Are Not Broken

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  • And of course, there are no “studies” that link red meat with CVD that aren’t countered (or bettered) by “studies” that show no correlation, with CVD, or more importantly, all cause mortality ( for one).

  • Alex Kohler

    Another health scare thwarted by …. actually reading the study.

    • Funny how that works. But man, in this case the authors weren’t much help…

  • Laura James

    I haven’t read all the posts but I did like Andrew Kim’s blog about it all. Plus did you look at his food intake and the amount of nutrition in that food? Crazy what he eats (not paleo) and how nutritious it looks on paper.

    • I’ve never fully understood what the 80/20-paleo-deal is, and as best as I can tell it really doesn’t have a hard and fast definition. But, under that rule, Kim’s probably just as Paleo as others who identify with the diet. If he’s eating swiss chard, milk, sardines, shrimp, grapefruit, lemon juice, and coconut water…he’s doing pretty good nutritionally speaking, for sure. And heck, If you replace his pepsi and marshmallows with sweet potatoes / rice / bone broth based meat & vegetable soup / liver / etc…he and I would have pretty similar diets (on that given day, anyway).

      • Laura James

        For sure:) I know I’ve gotten WAPish off and on depending on what I felt I needed at the time. I even tried Ray Peat style eating for a month or two b/c his writing is so compelling. N-1 just can’t be monetized. I hope:)

  • The authors of this study clearly misinterpreted the results to garnish a media frenzy and promote public outcry. Whether the study is valid or not, it seems they achieve the goal for themselves and their funding agencies.

    • Unfortunately, you’re absolutely right.

      We’ve made a lot of noise about the BS, but when you do look at the list of big media outlet stories that I listed at the beginning of the article…any single one of them will reach more people than all of the blog articles of the Paleo Community combined. And when you combine them all…forget about it.

      Even though the stories are filled with ‘shocking ignorance,’ ‘runaway inferences,’ and they’re filled with ‘nothing new’ — the take-away from most of the population is that here’s yet another reason why red meat is bad.

      • I wasn’t inferring that we shouldn’t talk about it. In fact I think we should. There needs to be an outlet or a voice of reason. What I mean’t was simply that the obvious intention was to taint red meat and they have done it exceptionally well. I mean a publication in Nature is amazing for any scientist, it is sad that it is more a matter of newsworthy science than good science.

        • Agreed — that’s what I thought you meant. I’m just pointing out the magnitude of how well they succeeded at tainting red meat. I agree we should be talking about it. And, even though CBS, TIME, the LA Times, BBC, etc. have huge audiences, we can still make a difference by talking about a) the science and b) how badly it was reported.

  • Will

    Do we know if urinary TMAO excretion is positively correlated with blood levels of TMAO? Perhaps it is, though it seems like Chris Masterjohn’s reasoning w.r.t. seafood is dependent on this assumption.

    I noticed that the authors of this paper are warming up to the idea that the adverse effect of saturated fat per se is small, if anything:
    “The high level of meat consumption in the developed world is linked to CVD risk, presumably owing to the large content of saturated fats and cholesterol in meat[1,2]. However, a recent meta-analysis of prospective cohort studies showed no association between dietary saturated fat intake and CVD, prompting the suggestion that other environmental exposures linked to increased meat consumption are responsible[3].”

  • Marie Lynette Johnson

    How do you pronounce phosphatidylcholine?

  • Mark Sissel

    I have never seen a person with a poorer understanding of science than Anthony Colpo. His writings demonstrate his lakc of education on the topic. Jamie Hale, Armi Legge, Paul Jaminet and Mark Sisson are not too far behind. All of those people are Internet crackpots.
    Salesmen will do anything and say anything to SELL you something.

    There is no such thing as “the scientific method.” It does not exist and never did. There is NO single method that all scientists follow. There are many specializations in science using many different methods. Many fields using very, very different methods. This is well understood among actual professional researchers in the real world. Most science is NOT experimental evidence, but very detailed observation.

    There are enormous amounts of methods scientists use. Anthony Colpo is laughable. He is not a valid source of anything as he has already demonstrated he does not understand the first thing about what science is or how it actually works. Equally uneducated Internet Bloggers fall for his nonsense.

  • ALL of us are FLYING BLIND regarding optimal diets. Too little is known. Scientists are still unravelling how cells work and how nutrients affect them. The unknowns are ENORMOUS. We have not even identified nearly enough about gut microbiota. We at least know it is CRUCIAL to health. ALL of these Internet salesmen are SCAMMERS- from Anthony Colpo to Mark Sisson to Lyle McDonald to Paul Jaminet.

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  • STOP quoting Anthony Colpo…..

    He is a disgraced Internet charlatan who has been publicly exposed by numerous people including PLantPositive and myself.

    . I have had his “picture ” THOROUGHLY ANALYZED by FOUR INDEPENDENT photography experts. Their conclusion was UNANIMOUS: IT IS MOST DEFINITLEY ALTERED AND MANIPULATED. They told me it is a POORLY EXECUTED HEAD GRAFT as well. Plus, the body light does not match the head .

    Colpo is DEFRAUDING the public with PHONY, erroneous pictures of himself, PLUS abusing science for profit……