Updated: Mar 3, 2019
Lately you hear it all the time, eat this don’t eat that. Steak causes heart disease, bacon causes cancer, fish is unsafe, but is it all true? I mean seriously, now both the media and blogosphere are on another feeding frenzy with the latest report from the World Health Organization (WHO). Why? Because WHO classified cured and processed meats as carcinogenic to humans and red meat as probably carcinogenic.
Really! They did. But what does the research actually tell us about the link between red meat and cancer? Let’s face it, for decades, we were told not to eat red meat because of the cholesterol and saturated fat it contains. When that argument became less convincing, a new one was offered in its place: we shouldn’t eat red meat because it increases production of a substance called TMAO, which causes heart attacks. Then red meat allegedly caused diabetes, and now red meat causes cancer!
The World Health Organization has ranked bacon, sausage, and other cured and processed meats as “group 1 carcinogens,” which puts them in the same category as tobacco, asbestos, alcohol, and arsenic of all things. It also placed fresh red meat in the “group 2A” category, which suggests that it is “probably carcinogenic” to humans. It’s the same old tired argument running since 1975, meat causes cancer, and frankly it’s wrong! I mean do we really think that eating a slice of bacon is the same as smoking a cigarette or breathing in asbestos? Let’s look at the facts, and WHO, you should do that too.
The association between fresh red meat and cancer is not a strong one, and in fact is often not distinguishable from chance. But let’s put it into perspective. If red meat really did cause cancer, you would expect to see a linear (or continuous) increase in cancer rates as red meat consumption increases. But that’s not what we see. In fact, some studies show a decrease in cancer rates in people who eat the most red meat. Vegetarian diets are not necessarily healthier either. Some studies have found a higher incidence of cancer in vegetarians.
The problem begins of course with the generalization of “all” red meat. Fact is red meat is technically any meat that comes from a mammal. That means meat from cows (beef and veal), pigs (pork), sheep (lamb and mutton), and yes, deer and bison all count as red meat too.
White meats come from fish and poultry. The color difference is dictated by the amount of a protein called myoglobin and the type of muscle in the meat. So, red meat is made up of muscles with fibers that are called slow-twitch fibers. These muscles are used for extended periods of activity, such as standing or walking, and need a consistent energy source. The protein myoglobin stores oxygen in muscle cells, which use oxygen to extract the energy needed for constant activity. Myoglobin is a richly pigmented protein. The more myoglobin there is in the cells, the redder, or darker, the meat. Obviously white meat is generally fast twitch muscle which has less myoglobin in it, so it appears less red. Now here’s the caveat. There’s a poor correlation with myoglobin and cancer! Hmmmm. But, myoglobin can become toxic (and carcinogenic) when a statin drug is taken. Yep, the problem is that myoglobin becomes ferryl myoglobin in the presence of excess amounts of free radicals and hydrogen peroxide. And statin drugs cause hydrogen peroxide to be formed in the mitochondria. We can also look to processed carbohydrates and sugar which produce more free radicals, also contributing to the production of ferryl myoglobin, and thus the higher risk of cancer. We could also add acrylamide to that mix too, a cancer-causing and potentially neurotoxic chemical created when carbohydrate-rich foods are cooked at high temperatures, but WHO did not look at that. So it’s not necessarily the meat consumption as an isolated factor which can contribute to cancer.
So, there is no simple way of isolating a certain kind of meat in the American diet and stating that it was a cause of cancer. It is also important to understand that the way the animal you are eating is raised actually determines how healthy that meat ultimately is. Take for instance an animal that has been raised on grains and other unnatural foods. Yep, talking about conventionally raised beef. After weeing these calves are placed into large feedlots called Concentrated Animal Feeding Operations (CAFO’s), which tend to be dirty, nasty places filled with disease. So much in fact that the cattle must be regularly injected with steroids and antibiotics to keep them disease free until they get to be processed. These same cows are rapidly fattened up with grain-based feeds, usually made with a base of soy or corn. It’s important to understand here that the quality of the meat at market is predicated by the nutritional content of the food the animal was fed. You simply cannot get healthy meat from an unhealthy cow any more than you can lower your disease risk by eating a fast food diet.
As I mentioned, these conventionally raised cows are often given drugs and hormones to grow faster, as well as antibiotics to survive the unsanitary living conditions. The cows live there for a few months and are then moved into the factory for slaughtering. Here’s where the problems begin. The antibiotics are passed on to us through the meat, and as you know antibiotics destroy your gut flora, where most of your immune system resides. The grains they are fed, which is basically GMO soy, corn, hay and some supplements has been associated with cancer in rats. The hormones used are typically synthetic hormones to help the animal grow. In our toxic world, hormonal pathways are often disrupted by synthetic hormones, which are also found in medicines, lotions, plastics and the environment. All of these synthetic hormones are associated with cancer. Can we really then say that meat alone is a carcinogenic product when the living conditions of the animal and the drugs and food it was fed were all unhealthy?
Then, of course, there’s processed meats. Processed meats are any meats that aren’t fresh. People typically think of processed meat as only referring to pork and beef, but this category can also include poultry (chicken, turkey, duck) and fish. A processed meat has been modified from its natural state, either “through salting, curing, fermentation, smoking, or other processes to enhance flavor or improve its preservation or both.
Processed meats include sausages, hot dogs, corned beef, beef jerky, canned meat, meat sauces, and lunch meats. But these meats are rarely ever eaten alone. Even a hot dog will have a processed bun with it, as will any deli meat sandwich! So to say that the processed meat alone was the cause of the cancer is difficult. But let’s get back to the WHO report. In the New York Times the headlines read “Meat Is Linked to Higher Cancer Risk, W.H.O. Finds” . Note they use the word “linked”. But NPR stated that processed meats “caused” cancer! So what is it? A link and a cause are two different things.
The WHO have a five tier system of categorizing something to be carcinogenic. In their Group 1 category they say that any compound within this group is carcinogenic to humans. Here they list things like acetyldehyde, acrylamide, arsenic, asbestos and benzidine to formaldehyde, radium and x-rays. They place fresh meat into Group 2A, as something probably carcinogenic to humans! To be fair, processed meat consumption has been linked to cancer, especially colorectal cancer. It’s a correlation or “link” backed by statistical observation. Large-scale studies from Europe and Japan have shown that people who consume more processed and red meat are more likely to develop cancer. But the question still remains whether this is anecdotal or not. The problem is that studies that link red meat to cancer are plagued by something called “healthy user bias.” This is a fancy way of saying that people who engage in one behavior perceived as healthy are likely to engage in other behaviors they also perceive to be healthy. On the flip side, people who engage in one behavior perceived to be unhealthy are likely to engage in other behaviors perceived to be unhealthy. See the problem? In an ideal world we might want to study these people by controlling what they eat as well as other known carcinogenic variables. But you cannot do that. So we are left with observational studies that simply draw conclusions from probabilities.
So, Regardless of whether consuming fresh and/or processed red meat is unhealthy or not, studies like this do nothing for changing that perception. Look, people in observational studies that eat processed meat may also have a tendency to smoke and drink more, eat fewer fresh fruits and vegetables, exercise less, and engage in other unhealthy behaviors that could influence cancer risk. This isn’t just speculation, its fact. Plus you need to also account for other things that the person having cancer may have come into contact with. BPA might be an issue, fluoride in their drinking water, glyphosate in crop production along with other contaminants might be the issue, and so on. If that’s not enough let’s point out the obvious. People who ate that big hamburger, likely did it with a gluten filled preservative rich bun. They likely had French fries with it too, cooked in GMO vegetable oil, and they swished it down with a soda! I wonder if they had a swirl cone for desert too.
And what about that processed meat? Curing meats involves adding salt, sugar, nitrates or nitrites to preserve foods against bacteria-induced rot and maintain flavor, though the most validated suspects in the cancer drama are nitrites they all likely contribute. The enzymes in meat tend to convert nitrites into nitrogen oxide and nitrous acid. Both of which can chemically react with amino acids found in our own proteins to form N-nitroso-compounds or NOCs, a class of carcinogenic compounds also sometimes described under the banner nitrosamines. To be fair, the other preservatives can actually become nitrites thanks to chemical reactions mediated by our own cells and by bacteria in our guts, or by bacteria naturally found in meat. NOCs are also spawned by chemical reactions with heme, the red pigment/compound responsible for binding oxygen in blood cells.
And what about the health of the subjects? Did any of them have preexisting low vitamin D3 levels? That has been shown to have a direct correlation with increased bladder cancer risk, increased breast cancer risk, and colon cancer too. And what was the condition of their gut bacteria?
One paper compared the gut microbial population of 60 patients with colorectal cancer with that of 119 normal controls. The patients with cancer had significant elevations of Bacteroides/Prevotella (both species that are recognized as potentially harmful) when compared to the control group, and the difference was not affected by general patient characteristics (e.g., age, body mass index, family history of cancer, tumor size or location, or disease stage). It is a fact that antibiotics destroy gut flora which would ultimately have decreased the participant’s immune system.
What I am trying to say is that other factors are likely in the mix too. If we look at cancer research in the UK and how they make correlations to smoking and red meat consumption we begin to see that it’s a specific set of risks that likely increase cancer, not a single item. In other words, if you have a highly processed carbohydrate diet with soda, red meat and you smoke, your risk is higher than if you exercise, don’t smoke, only eat free range meat and avoid sugar.
Rest assured, it’s impossible to determine if an individual will get cancer based on a lifestyle choice, whether it’s smoking or eating processed meat. Cancer occurs when a healthy cell acquires enough mutations to start replicating uncontrollably and to spread into new organs away from its site of origin. That means that synthetic chemicals, pharmaceutical drugs, fast food, smoking, pollution and a host of other things are contributory. Besides that, the mutations can vary dramatically among the types of cancer (lung, pancreatic, colorectal, etc). They can even differ within a subtype, meaning a pancreatic cancer from one person can be genetically dissimilar than a pancreatic cancer in another. So could one item be the cause of all of the cancers? It’s unlikely, plus, a malignant tumor in a single individual is constantly evolving, and there is evidence suggesting that no two cancer cells in the same tumor are the same. And that brings us full circle to the question of whether red meat causes cancer.
Fact is, a cell’s ability to acquire mutations depends on personal genetics — whether or not you inherited a predisposition from mom and dad — and exposure to compounds that are genotoxic; that is, that can change your DNA. We know that synthetic chemicals are genotoxic, and so are many pharmaceutical drugs. So it’s not necessarily the meat, but the way in which the meat was raised and processed! Many deli meats for instance come from grain fed, hormone grown, antibiotic protected, sick animals! Is that our perfect storm?
My conclusion is simple. If you eat processed meat, drink soda, eat fast food, processed carbs and smoke; then you don’t exercise, allow yourself to become overweight; which leads to illness, more antibiotic use, pharmaceutical intervention and stress, then don’t be particularly surprised if your health suffers because of it.
WHO says they looked at data going back to 1966 but use of free range grass fed versus grain feed, antibiotics or using hormones fell outside of the WHO’s report. Simply, they did not consider it!
So, should we give up meat altogether? I would give that a resounding NO!
It’s important to remember the distinction that the WHO report makes between processed meat and red meat. They stated that “Processed meats even in small amounts were increasing risk — a little less than 2 ounces [which is equivalent to] a hot dog or few slices of cold cuts,” But in reality the way the food was produced (processed) and then prepared has the final say on whether it is carcinogenic or not.