“RED MEAT CAUSES HEART DISEASE!” reads the headline – again, but this time not because of fat or cholesterol, now it’s l-carnitine. They are singing the same old song, but this time it’s to a different tune. Old habits really do die hard.  As anyone who has embarked on the type of lifestyle changes we espouse here at Calton Nutrition knows, you are often met with a lot of brush back from friends and family who say, “that's great for you, but I could never give up (insert food here).”  Of course a healthy lifestyle is a lot easier than many people think, as we clearly illustrate with our simple and easy to use Grocery Purchasing System (GPS) in our recently released book, Rich Food, Poor Food.  It's really more about making informed choices based on years of human experience, research, and common sense than it is deprivation.

Unfortunately, the scientific community seems to be finding it hard to give up their old ways.  For several decades, many have tried to vilify saturated fatcholesterol and red meat in particular, as the cause of a host of chronic diseases.  However, as we have covered in previous blogs and will again in the future, the evidence simply does not back this up.

A big story in the media lately had been a study by Koeth et al. (2013), in the journal Nature Medicine, linking red meat to heart disease by way of trimethylamine-N-oxide (TMAO).  In case you've been living in a cave (perhaps a few of the Paleo/Primal types have), the basic premise to this story is that Koeth and his team of researchers, showed that l-carnitine, an amino acid found in large quantities in red meat, gets metabolized by your gut bacteria and that a potentially deleterious by-product of this process, is the production of TMAOs.


Now we could spend a long time dissecting the inherent flaws of this study, but lets just focus on the pertinent stuff to make it easier for everyone to understand why eating organic, grass-fed, pasture-raised red meat is still a centerpiece to health.  As our colleague Chris Kresser excellently pointed out, “The study itself, and even most of the media articles about it, quite simply and without much fanfare stated that saturated fat and cholesterol have little to do with the supposed increase in heart disease observed with red meat consumption.” 

Read that again, “The study itself… stated that saturated fat and cholesterol have little to do with the supposed increase in heart disease observed with red meat consumption.”

This type of information should have been shouted from the rooftops!  However, in spite of this study reaching similar conclusions to those in the meta-analysis by Micha et al. (2010), in the journalCirculation, showing that saturated fat, cholesterol, and red meat have little, if anything to do with the development of heart disease, what was instead proposed was a new mechanism to keep this myth alive.  If they can’t win with fat and cholesterol – it looks like they are going to try a “Hail Mary” with l-carnitine. Talk about old habits dying hard!

Come on guys…isn’t it really about gut bacteria?

Rather than being a condemnation of red meat, this study is more a testament to the importance of maintaining proper gut microflora.  First, the meat used in this study was likely sourced from concentrated animal feeding operations (CAFO) an unnatural industrial farming process that can cause a host of health issues for both the cattle and the consumer.  These cows have been crowded and fed an unnatural diet of corn, wheat, soy and even candy, causing them to become breeding grounds for disease, which in turn necessitates the use of antibiotics and hormones to ensure proper growth for market.  These chemicals subsequently enter our systems when we eat them, altering our gut bacteria – remember ANTI-biotics kill off the good PRO-biotic bacteria.

Eating this factory-farmed meat may create an environment that causes the “bad” bacteria in the gut to run more rampant and produce more TMAOs.  Now, while the vegan and vegetarian populations in the study did show lower levels of TMAO production, is this purely an effect of the red meat consumption, or of other lifestyle choices for gut health?  From a statistical perspective, those who are “health conscious” eat more vegetables, fruits and probiotics and less refined, processed food.  All of these are behaviors that would foster a more beneficial environment for gut microflora.  This is known as the “healthy user bias” and is another confounding factor in drawing any definitive conclusions from the Koeth study.

Other common sources of TMAO production by gut bacteria include choline and nitrites.  Now we already covered the nitrite issue in our blog on bacon, but it bears repeating that both of these substances are common components of vegetables.

If choline and nitrates are common components of vegetables, why was there minimal TMAO, production in the vegan and vegetarian populations?  This brings us back to the potential protective effect of achieving a healthy gut microflora; these plant-based dieters, on average likely had a better gut bacteria environment than the standard American meat-eater, due to the “healthy user bias” phenomena.

In fact, upon administration of a dose of antibiotics targeted towards the TMAO producing bacteria (as opposed to the general ones we would receive from eating CAFO meat), TMAO levels logically went back down.  But rather than the researchers saying, “gut bacteria linked to heart disease,” this study stays on the red meat alarmism tract with more scare tactics.  Like we said, old habits really do die hard.

So what does all of this mean from a practical standpoint? 

It is clearly not time to dispose of all that organic, grass-fed pasture-raised red meat in your freezer just yet.  The wiser choice would be to beef up you gut bacteria by enjoying that healthy meat with as many vegetables and probiotics, such as fermented sauerkraut, kimchi, fermented beverages, and organic, grass-fed, pasture-raised yogurt and kefir, and your dietary profile allows.  You can find our certified Rich Food choices for each in Rich Food, Poor Food. While l-carnitine as a reason not to eat red meat will likely go the way of saturated fat and cholesterol, the study did bring an important issue to light, if you ensure a proper gut microflora, you will be well on your way to living your optimal life. We’ll have our grass fed steaks rare please.