Cooked Meat- The Mutagen in a Bite, Heterocyclic Amine Exposure

There is no known animal in nature except modern humans that grills meat. This is not an evolutionary congruent process that is causing serious maladaptation.

Heating of amino acids in the presence of creatine and monosaccharide sugars creates mutagens known as Heterocyclic Amines (HCA). Our body does not recognize them as different and integrates them into the cells. These amino acids have been damaged due to heating and their molecular form is changed. This integration into healthy cells causes mutations in DNA. Cancer is one of many correlated diseases.

Paleo people who like lean meat somehow forget that in the Paleo period most prehistoric people did not live long enough to die from cardiovascular disease or cancer or suffer from chronic diseases. In extremely harsh conditions where the average life expectancy is 32 years of age, the genes that get passed along to younger generations are the ones that are just old enough to go to reproductive age by any means necessary. That means not dying of starvation or disease or in an attack. The more calories we consume, the better no matter what they are. The meat cancer link is not really of any concern.

Eating raw meat from decaying carcasses is not our food. It would take just a couple of hours after death in climate conditions in Africa for meat to spoil.

Carnivorous species deal with bad microorganisms with strong stomach acid. The capacity of the carnivore stomach to emit hydrochloric acid is outstanding. Carnivores can hold their gastric pH all way down to around 1 or 2, even with food present. Strong gastric pH facilitates protein breakdown and is necessary to kill the abundant amount of dangerous microorganisms frequently found in rotting flesh. Their digestive tract is sterile and there is no large colon for fermenting fiber or other foods. Meat is digested in a couple of hours and excreted out. In carnivore animals, transit time is very short. Types of bacteria in the intestine are different also.  When we eat a rotten apple, we might get drunk, but if we eat raw decaying flesh, there is an excellent possibility of severe consequences and death.

In certain conditions when there is an absolute need, the herbivorous animals will eat available meat only to survive. And the meat has to be cooked.

Let me give one example of how chronic diseases occur and progress so that we can start to understand this. The most common nervous system disorder of all neurological disorders is something called essential tremor (ET). It usually involves an involuntary shaking of the arms, hands, or fingers but sometimes it can also affect the head, vocal cords, or other body parts. It is a different condition than Parkinson’s disease but is often misdiagnosed as such. In most severe cases, ET interferes with a person’s activities of daily living, like dressing, taking care of personal hygiene, feeding, and is generally progressive in most cases. Some people have it in families so genetics plays a role and will develop symptoms at an early age but it is not bad genetics that is the real problem, and I will explain.

What happens is that when we heat amino acids (building blocks of protein) in the presence of creatine and monosaccharide sugars, they have a reaction and amino acids lose their molecular form.

What that means is that they are different but not that much, and that is the problem because our body does not recognize them as different. It thinks that they are just regular aminos. Meat cancer is a correlation caused by this mutagenicity of Heterocyclic Amines (HCA) but so are many other different conditions.

We are still not fully adapted to our new lifestyle and as a consequence what happens is that they start to be incorporated into our cells. Because their molecular structure is different, it causes problems in the form of mutations. Having mutations maybe sound like a good idea for an SF movie, but in real life it kills.

It causes changes to DNA. Meat heated at high temperatures, especially above 300 °F (as in grilling or pan-frying), or that is cooked for a long time, tends to form more of these mutated heterocyclic amines (HCAs).

For example, well done, grilled, or barbecued chicken and steak all have extreme concentrations of Heterocyclic Amines (HCAs). Chicken is the worst of them all actually, with around two times more of this carcinogen than beef or pork. Marinating meat before cooking in some form of antioxidant-rich marinades like garlic or rosemary seems to help. Garlic at 20 gm/100 gm marinade reduced carcinogen production by about 70%. In contrast, regular barbecue sauce that contains much sugar caused a significant increase in chemical formation, tripling the levels after 15 minutes of cooking.

There is a list of different types of these messed-up heterocyclic Amines in cooked meat that are created. PhIP (2-Amino-1-methyl-6-phenylimidazopyridine) is the most abundant one. Long-term rodent studies confirmed that PhIP causes mammary gland and colon cancer. The most toxic and mutagenic of all is MeIQ. MeIQ is precisely 24 times more carcinogenic than aflatoxin, and aflatoxin is one of the most toxic substances ever created by mold. All of the other ones, and there are more than 20 HCAs, are more toxic than benzopyrene. Benzopyrene is a primary carcinogen that does the most damage in smokers and is found in cigarette smoke and coal tar.

Smoke actually at the same time during cooking creates a list of other different mutagens named polycyclic aromatic hydrocarbons (PAHs). Cooking techniques that expose meat to smoke or charring contribute to PAH formation. PAHs are created with the high-temperature cooking of meat. For example, when fat and juices from grilled meat drip and cause flames, the fumes will be filled with PAHs that will then adhere to the surface of the meat. Any form of burning can create them, for example, coal, oil, gas, wood, garbage, and tobacco have them too. They are also formed where smoke is used such as smoking of meats.

These unnatural mutagens (HCAs and PAHs) that are formed with unnatural activities such as grilling are capable of damaging DNA because of our lack of adaptation to them. The body has a line of specific enzymes to neutralize these mutagens.

Researchers have discovered that the action of those enzymes differs significantly among people. And that is a problem. In individuals who have lower levels of these enzymes, exposure to these compounds may be associated with an increase in cancer risks. Some of us can cope better with detoxifying these mutagens and some can’t and will have a higher risk of cancer. And that is what is called a genetic factor in medicine. It is not that we are born with bad genes, and that is it, you will get cancer or you will not. The situation is more complicated than that.

Of course, some level of cancer happens in animals too, but 23.4% of all deaths are not from genetics. It is an epidemic of biblical proportions because it is, in essence, a form of maladaptation to our environment.

One of the HCAs that is formed is Harmane. Harmane is a neurotoxin that is strongly associated with essential tremors. If exposed by injection mouse will develop an extreme tremor in just 3.1 minutes after the exposure and the tremor would last for hours. Because it is fat-soluble, it will accumulate over time in all fat tissues including the brain. It is found in elevated levels not just in the brains of ET patients but also in Parkinson’s disease. When compared to the control group Harmane concentration is precisely 50 percent higher in the brains of essential tremor patients. It is also elevated in blood samples too. If there is a patient that has a family history of essential tremor blood work results show the highest concentrations of all people.

Essential tremor is liver enzyme detoxification disease, a form of maladaptation. People with ET but without a family history will have little lower levels than people with a family history but still well above normal levels. Elevated Harmane in ET is due to an inherited reduction in the capacity to metabolize it out of the system. Same with any other disease, some people are more prone to it some less, but none of us are immune completely. That is why we see that with time the percentage of people with the disease goes up. From 4% in the 40s to 20% in the 90s. If we managed to live long enough most of us will eventually get it, except for the people who do not consume it. For each additional 10 grams/day of meat consumed, the odds of ET are increased by 6%.

Now you might not get ET, all of this is a just small example for logical understanding. You might just get cancer. The real difficulty is that there is a long list of different chronic diseases to make a pick from depending on individual genetics.

References:

Passages selected from a book: Pokimica, Milos. Go Vegan? Review of Science Part 1. Kindle ed., Amazon, 2018.

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