Red Meat Scapegoat: The New York Times & Heart Disease


If you’re paleo or Bulletproof, by now you may have heard about the New York Times and Forbes articles on a new study about red meat purporting to link it to heart disease. This post is to protect your meat rights with accurate, unbiased science.

Most people know at least one person who has – or will have — heart disease. Hundreds of commercials each day advertise drugs for heart disease. A constant drumbeat of news articles condemns saturated fat and meat as the culprit in heart disease, fueling fear with attention grabbing headlines.

Heart disease impacts all of society, even if we aren’t going to get it because we have sky high HDL (“good” cholesterol) and near zero inflammation.

That’s why scientists are working on novel ways to understand heart disease, and also why it’s so tempting to use breakthrough research to write catchy news headlines demonizing red meat. Let’s dig in on the last high profile recent news and see what it actually means for you and your health.

Yesterday, the good people at the New York Times and Forbes recently published short articles based on a very detailed and amazing new study. The articles didn’t have space to cover the details, and the study itself suffers from only a few of the same (at least to biohackers) flaws from which most studies of red meat suffer.

Articles like this are damaging when the science and the headlines don’t match. Dozens of Bulletproof readers and friends emailed and posted questions asking for my take on this article, so here is the Bulletproof perspective on what we can learn from this study and what it means for you.

Summary of the article

The basic point of the headline was that eating red meat caused heart disease, but the study referenced showed that a chemical called TMAO (trimethylamine n-oxide), a byproduct of gut bacteria eating lots of things including red meat, gets into the blood stream and theoretically increases the risk of heart disease. Despite the headlines, what the study really showed is that disordered gut bacteria cause heart disease. This TMAO effect – if it is significant, which this study says it is – is a gut biome issue, NOT a meat issue. The words “in a microbiota-dependent” showed up 8 times in the 10 page study, but the headlines said “meat.”

This is the logic in the study: (1) Meat contains an amino acid called carnitine (2) gut bacteria only found in meat eaters use carnitine to fuel and multiply (3) TMAO is a byproduct of that process (4) Hypothesize that TMAO helps cholesterol get into artery walls, therefore TMAO levels are a predictor of heart disease. With that process in mind, this study conclusion is not half bad. Here are some things to think about, keeping in mind the research included a lot of mouse work and some human data:

A) In the human part of the study, the researchers measured effects of CAFO (Concentrated Animal Feeding Operations) industrial meat with antibiotics known to impact gut bacteria, NOT grass-fed or even just antibiotic-free meat, and didn’t control for the presence of antibiotics, or their impact on gut flora.

B) The human part of the study used cooking methods proven to create nitrosamines, which are precursors to TMAO (searing at high heat, George Foreman style, is not Bulletproof).

C) The media failed to acknowledge that TMAO is a byproduct of digestion of a lot of things including vegetables (via nitrite) and choline found in vegetable oils.

D) False basic assumptions about what causes heart disease (based on longstanding cholesterol propaganda) led to a misinformed analysis and conclusions of data.

What kind of meat was it really?

The researchers most certainly measured widely available CAFO industrial meat because the relied on data from patients who visited a hospital. CAFO meat comes with a host of issues for the human body. First, CAFO meat contains antibiotics that alter the gut biome and could solely be responsible for the noted effects. The vegetarians in the study did not show the same rise in TMAO levels as the regular meat eaters because, most likely, the antibiotics from industrial meat had not impacted their gut bacteria.

Hands down, the average careful, educated vegan has a healthier gut biome than the average standard American meat eater. This is why I NEVER eat non-grass fed beef or lamb. Instead, I’ll fast or eat butter and vegetables to get by. The scientists did not measure what else was in the meat! It is unscientific to base a study on an assumption that every piece of red meat has the same things in it when we know that’s not the case.

CAFO industrial meat also calls into question the presence of mycotoxins that accumulate in the tissue of animals eating corn and grain. Corporate CAFO operators test for mycotoxins in animal feed, not to avoid feeding it to their animals, but so they can buy cheaper (moldier) feed, and feed it to their animals at levels just below what will kill them or cause them to lose weight.

Mycotoxins are a major contributor to heart disease according to over 900 studies published by AV Costantini in a groundbreaking series of books titled Fungalbionics. Some of his studies link mycotoxins to arterial lesions which the body tries to repair, creating the arterial plaque. You can find entire posts dedicated to addressing mycotoxins in our food, especially coffee and meat, and the effects they have on our minds and body on this site when you just enter “mycotoxins” into our search bar.  My best mycotoxin video is here.

How was the meat prepared?

The article explicitly states, “The researcher himself bought a George Foreman grill for the occasion, and the nurse assisting him did the cooking.” The researchers didn’t think outside the scientific box. Searing as a cooking method creates more of a known carcinogen – nitrosamine! Nitrosamines are methylated by bacteria in the gut, which forms a substance called dimethylnitrosamine, which is a very toxic breakdown product of TMAO, the very substance the scientists were investigating. Did the paper measure the presence of nitrosamines in the meat after cooking, or test whether the inflammatory effects of it were at fault? Nope… but they did show that the straight carnitine has an effect on TMAO levels in people with some kinds of gut bacteria, so at least some of the cause is not from the overcooked/burned meat.

What else raises TMAO?

TMAO levels mattered before this groundbreaking new study, and they matter even more now. Biochemistry shows that TMA and TMAO are precursors of dimethlynitrosamine, which is linked to cancer, cellular immunity problems, and liver cirrhosis, which are linked to heart disease. TMAO itself fuels the growth of e. coli and salmonella and other gram negative bad bugs that are linked to heart disease. Note how TMAO doubled the growth rate of bacteria below. The research report didn’t look at TMAO’s impact on TMAO consuming gut bacteria.

Table 1 - Bacterial reduction of trimethyldmine oxide

Given this dark conclusion about red meat, this media treatment does us a great disservice by failing to acknowledge that carnitine is NOT the ONLY producer of TMA and TMAO. Choline from vegetable oils was acknowledged in the study as a source, but not nitrite (highest in vegetables), which also forms TMAO when digested by certain bacteria in the gut.  The smoking gun is which bacteria are in the gut!

In fact, some bacteria break down TMAO to TMA (trimethylamine). There is a condition called trimethylamuria where bacteria that make trimethylamine, normally found in your bowels, escape into the circulatory system, and produce an offensive fish-like smelling body odor. This smell can come out in your sweat, urine, vaginal secretions, and breath.

Given this information, and the New York Times article, you could argue that having fishy BO is a sign for risk of heart disease. In my experience, fishy BO is a sign of toxins in the body, and probably too much protein consumption, or an impaired ability to digest it (betaine HCL and protease enzymes help with this issue). Fishy smells from any orifice are definitely not Bulletproof.

The researchers sequenced the gut bacteria  (of a mouse) and found species that increase and decrease TMAO levels, and found they made more TMAO in mice that regularly had carnitine added to their (very crappy) mouse chow. Sadly, mice proboitics and human ones do not overlap much.  While they did sequence human gut species (hooray!), they did not publish which strains specifically raised TMAO.

The real point is that the problems point to TMAO, so the real area of further investigation is the gut biome – not the (grass fed, antibiotic free) red meat isle. The researchers showed that reducing bad gut bacteria (with antibiotics) stopped the problem. Why didn’t the media jump on this?  A better headline would be, “Study shows gut bacteria cause heart disease.”

The researchers may also have missed a very important point. They proved that TMAO reduces the size of the bile acid pool in the body, which is amazing knowledge. On the Bulletproof Diet, we work to promote bile acid turnover because fat-loving toxins hide in bile, and those toxins are tied to atherosclerotic lesions. A reduction in bile acid would cause a proportionally much higher recycling of these toxins.

Sneaky assumptions based on failed cholesterol hypothesis

The researchers bought in to the cholesterol propaganda, which led to a well-intentioned but misinformed analysis and conclusions. The proposed theory is that TMAO enables cholesterol to get into artery walls and also prevents the body from excreting excess cholesterol, so therefore it causes heart disease. The truth is, unoxidized cholesterol, especially HDL and even LDL, of correct particle size, is NOT harmful to arteries and can be even beneficial for muscle growth and toxin elimination. Heart disease starts with artery inflammation, and LDL can be a sign of inflammation.  So instead of focusing on cholesterol, we could instead focus more on things that cause artery inflammation as a cause of heart disease. Thus, the anti-inflammatory Bulletproof Diet, and my recommendation to measure LP-PLA2 as a marker of arterial inflammation.

Finally, this study shows that L-carnitine lowered cholesterol, added significant muscle mass, increased energy, and caused fat loss. Maybe these test subjects didn’t have bad bacteria in their guts, who knows. Plus, they were 100 years old. Another form of carnitine, ALC, has stellar anti-aging research associated with it. The researchers acknowledged that carnitine may be good for you according to some studies. (I believe it is.)

The point is, restricting carnitine because you might have some gut bugs that make TMAO, which may or may not directly cause heart disease a bad idea. Fixing your gut bacteria and avoiding industrial meat filled with antibiotics and mycotoxins is a GREAT idea.

Bulletproof suggestions

  1. Avoid CAFO industrial meat, always. Choose grass-fed meat or don’t eat it.
  2. Avoid chronic low dose antibiotic exposure that will change your gut flora. Common foods that contain too many antibiotics include non-grass fed meat and non-organic dairy products. If you have SIBO or bad bacteria in your gut, kill it.
  3. Focus on fixing gut bacteria in your gut biome
  4. Eat a Bulletproof Diet.
  5. Make sure to consume bulletproof starch once every few days to feed gut bacteria, and a small amount daily if tolerated
  6. Take species-specific probiotics that work for you, if there are any. Be cautious with fermented foods – you have no idea what species you are eating, and they harbor a variety of toxins not widely acknowledged. If you eat fermented food and feel 100% bulletproof, then you’re probably ok.
  7. Stop eating mycotoxins which also impact gut flora.
  8. Consume XCT oil to keep excess gut bacteria and fungi at bay (Complete post to explain more about this will be published in the near future).




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