There are four chemical and biological truths to understand regarding how red meat cures heart disease:
1.) TMAO is a protective metabolite
2.) We make more when we experience more stress IN ORDER TO PROTECT US
3.) L-Carnitine is necessary for human life/makes TMAO; ergo, we will intuit to eat more IN ORDER TO PROTECT US
4.) Red meat is the L-Carnitine super food (contains the highest concentration)
TMAO is a healthy protective metabolite which combats several negative effects in the body. Without it, we would die. Primarily, we make it from the essential nutrient choline and a building block for healthy cell membranes called phosphatidylcholine. As an organism experiences increases in stressors or pressures, it makes more TMAO: https://en.wikipedia.org/wiki/Trimethylamine_N-oxide. We see this in a linear relationship in marine life. The greater the depth at which the creature lives in the ocean, the more TMAO it must produce to protect itself. Literally, there is more pressure on the animal. In order to make more TMAO to offset the effects of the great depth, obviously, the organism must eat more of the precursors which its body will use to make the TMAO.
Another pathway for TMAO synthesis is L-Carnitine, a beneficial amino acid derived from lysine: https://en.wikipedia.org/wiki/Carnitine . L-Carnitine is used not only to make this life-saving TMAO, but also as a transport molecule to burn fat. As such, L-Carnitine DEficiency makes it very difficult to manage healthy energy balance in the body.
L-Carnitine consumption reduces all-cause mortality by 27%, irregular heart rhythm by 65%, and cardiac-related chest pain by 40%: https://pubmed.ncbi.nlm.nih.gov/23597877/. There is some L-Carnitine in avocados and beans, more in dairy, fish and chicken, and the most in red meat. The role of L-Carnitine in plant life is currently less-understood; but researchers are working on it: https://www.researchgate.net/publication/326084307_Physiology_of_L-carnitine_in_plants_in_light_of_the_knowledge_in_animals_and_microorganisms.
To be clear, when stress happens, the animal makes more TMAO. When the animal makes more TMAO, the animal will make/require more of the precursors which make the TMAO. In response, the animal will increase levels of L-Carnitine in tissue. Consequently, if it can, the animal will eat more foods which contain L-Carnitine.
You could flip logic upside down, throw away critical thinking, forget the proven biology, and propose that the causal relationship works like this:
For NO reason, an animal eats BAD foods which contain EVIL L-Carnitine, which forces the body to make DESTRUCTIVE TMAO, which CAUSES heart disease. Lol. There are actual paid scientists who’ve been proposing this for about 8 years. Clearly, they should’ve taken some courses in formal logic and critical thinking.
The precisely wrong way to look at these biochemical facts is to observe an overstressed animal, note that the animal defends itself by making more life-saving compounds, and then conclude that the compounds cause or create the stress, and THEN conclude that the foods the animal eats in order to protect itself cause the stress. That is faulty upside-down logic which ignores the known biological truths.
We can all see and agree that people who are experiencing too much stress will make more TMAO to offset the stress. But if we ignore the science and critical thinking, we can begin to believe that TMAO is the CAUSE of the stress. As we begin to confuse ourselves, it’s then very easy to conclude that L-Carnitine is BAD. As long as we forget the role of TMAO and L-Carnitine, we can use our ignorance to call them both BAD. And then it’s not a big jump to conclude that the L-Carnitine superfood (red meat) is also BAD.
Taking the same faulty logic, we would just as soon conclude that it’s the TMAO, and not the depth, that CAUSES a marine creature to experience more pressure. Stupidity.
It’s no longer sufficient to remind people that correlation doesn’t equal causation. We’ve come to a point where experts are paid to say the causal arrow is pointed the wrong direction entirely.