Meat, Dairy, Eggs, and Cancer: Quality over Quantity

colinchamp August 29, 2018 16 Comments

Author’s Note: Some of this article contains excerpted passages from within my new book, which should be released in the near future. Some of the topics were kept brief as they will be explored more deeply in the book.

Meat, Dairy, Eggs, and Cancer: Quality over Quantity

It has been nearly 2,500 years since Pythagoras used his prolific intelligence to begin describing the world through mathematical equations. We have him to thank for the geometry test questions in high school asking us to calculate the length of one side of a right triangle when provided the lengths of the other two, affectionately known as a² + b² = c². This relatively harmless mathematical equation would have large implications for the future health of the world.

Pythagoras, born on the Greek Island of Camos, would eventually leave his hometown to establish his philosophy school in the Greek colony of Crotone, 2,400 years before my great grandfather, Leonardo Pesce, would leave the same area for America. While Leonardo left on his own accord for a better life, the Pythagoreans were forced out of Calabria. Crotone is perhaps now best known for its famous Crotonese cheese and flavorful red wines.

In ancient Calabria, Pythagoras and his supporters followed a strict, monk-like set of guidelines, most of which were based upon leading an immensely disciplined and modest life. They detested modern luxuries and espoused a lifestyle that remained pure through abstention. Their depiction of a simple life, however, would differ drastically from the Calabresi when it came to food. Pythagoras was, according to the experts, even-tempered, humorless, and avoided the “pleasures of love, all in an effort to remain grounded.”¹ His even-temperedness was attributed to his diet, and he was, apparently, a strict vegetarian who required the same of his students. For unknown reasons, he also avoided beans, and his followers were advised to abstain from them, along with fish and meat. Some historians claim that Pythagoras believed that part of the soul would be expelled when passing gas, thus explaining his legume-phobia.

Strangely, the earlier followers of Pythagoras may have known him to eat meat, while the later followers, like Plato, believed he was a vegetarian. According to the student Porphyry, Pythagoras had recommended that he nourish his body by consuming meat, since after all, he was an athlete. The exact origins of the vegetarian Pythagorean view are unknown, but are likely related to his belief in metempsychosis, or the transmigration of the soul between physical bodies – more simply known as reincarnation. Some have even suggested that Pythagoras claimed he could remember his past lives.² Regardless of the contrasting views on the Pythagorian diet, in reality, it was likely that much of it did not include meat regardless of his philosophical and religious views, but rather due to geographical confines – his town was surrounded by “irrigated fields” and “desert wasteland.” To no surprise, meat was a luxury.

Regardless of the source, the attribution of vegetarianism to Pythagoras has persisted throughout the centuries, correct or not. The famous Roman poet Ovid relayed a story of him pleading abstention of meat to his followers in the famous epic Metamorphoses, furthering Pythagoras’ reputation as a vegetarian. Several English translations of the document additionally strengthened the relationship, eventually leading to its introduction into Shakespeare’s work, including The Merchant of Venice in 1596. The character Gratiano proclaimed that according to Pythagoras, “souls of animals infuse themselves into the trunks of men.” Eventually Leo Tolstoy, the famous Russian novelist and author of Anna Karenina, would partake in the “Pythagorean Diet,” abstaining from meat.

Tolstoy apparently followed a Pythagorean diet when not writing famous novels. It is unclear how he felt about beans.

A numerical mystic by nature, Pythagoras was also credited with the view that the planets rotated in harmony and under the laws of several mathematical equations. Much like the later famous vegetarian Leonardo Da Vinci, he firmly believed in a harmony between math, science, and nature, and surmised that there was a mathematical equation to describe most relationships in nature. This view was likely reinforced by his creation of a groundbreaking equation that predicts the lengths of triangles and is consistent throughout nature. His interlacing theories on mathematics and nature heavily influenced Plato, his famous understudy, and the many philosophers that followed him; this unification of mathematics, philosophy, and religion is perhaps best illustrated by Leonardo da Vinci’s Vitruvian Man, the famous drawing illustrating the perfect human body sketched by precise observations and mathematical calculations. In other words, the early mathematicians, scientists, and philosophers strongly felt that mathematical equations could describe the world around us.

Leonardo da Vinci had issue with harming animals and refused to eat meat (though he would cook it). As the model for Vitruvian Man, he still apparently had perfect proportions. Scholars began to describe many aspects of nature and the human body centuries ago.

So, what does Pythagoras and his mathematical equation with triangles have to do with animal foods or the pursuit of achieving optimal health to prevent cancer? According to Aristotle, Plato’s most famous student, it has everything to do with it. Plato’s viewpoints, philosophies, and teachings were purportedly heavily based on the beliefs of Pythagoras. Furthermore, these views were further expanded when Plato’s beliefs profoundly influenced the formation of many modern religions, including Judaism and Islam. His work also left a massive impression upon Christianity, which grew exponentially under the auspices of the Roman Empire as it expanded throughout Western Europe. While this influence is now widespread, Saint Augustine, for instance, was considered a Christian Neoplatonist due to the large impact of Plato on his religious views. A fervent theologian, Augustine created a total of 13 books as part of his famous work Confessions, influencing countless Christian writers throughout the Middle Ages and since.

While the massive influence of Plato’s views on modern philosophy and religion are well-established, the exact impact of his views on food – which included quantifying calories and avoiding meat – remains relatively unexplored as little discussion has broached the topic. Pythagoras’ vegetarian diet, regardless of the specifics, was supposedly further influenced by his following of asceticism. Asceticism shunned all sensual pleasures and was characteristic of many philosophers and religious figures of antiquity, from Plato, to the Christian Apostle Paul, and right back to Saint Augustine. Finally, perhaps the most famous Catholic philosopher, the ascetic Saint Thomas Aquinas blended the philosophies of Plato’s student, Aristotle, with the ideologies of Christianity. Pythagorean views – which eventually became Plato’s views – entwined the role of discipline with diet well beyond vegetarianism. According to Panagiotis Skiadas and John Lascaratos, from the Department of History of Medicine in Athens, Greece, “As opposed to the limitless desire for food and drink, self-restraint is considered by the philosopher to be the power with logic,” and the Pythagorean School “had enforced a series of dietary restrictions for consolidation of the spirit of self-restraint and healthy living.”³ Food nourished the body, but lack of food, according to the philosophers, nourished the soul.

The former act of utilizing the diet as a means of nutrition and survival, was instead replaced by the act of limiting the overall content of the diet along with the amount of meat and opsa (i.e. tasty foods) as a means of displaying self-restraint. Power over food signified power over mind. Indeed, the inconsistencies within Pythagoras and Plato’s actions and philosophy signal a deeper issue: it appears the differences between their views on science and philosophy profoundly conflict when it comes to food. They fully acknowledge that animal products are vitamin and nutrient-rich and are required to most adequately nourish the body. Yet, their religious views on reincarnation and philosophical views on asceticism lead them to an entirely different conclusion that emerges within their philosophical works.  Regardless of these issues, the belief of Pythagoras and Plato, along with their massive influence, would set the tone for calorie counting and fat avoidance for centuries to come.

Meat, Dairy, Eggs, and Cancer: Segueing into the Future

Fast forwarding thousands of years, viewing food as a mathematical equation has progressed far beyond a degree that even Plato could have imagined. The Dietary Goals of the United Stated were released in 1977, chastising those nutrient-dense opsa foods that Plato felt turned “flesh into flesh and bone into bone.” Yet, following Plato’s later views and his reliance on nutrient-sparse foods, the USDA watched as vitamin deficiency skyrocketed. The promotion of their triangular guide further condoned these foods, with the base including the promotion of foods that are so devoid of vitamins, nutrients, and minerals, that they must be added to them via factory-produced chemicals. The adoption of the mathematical pyramid paved the way for counting calories, avoiding dense foods, and instead, relying on often flavorless and nutrient-sparse sources of food. And so, Plato’s conflict – after perseverating throughout history – blossomed to full fruition; if not kept under check, food, a necessity of life and our most important physical being, the body, could quickly cause rotting of our most important metaphysical being, the soul.

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In other words, during Plato’s time, philosophers began to quantify those rich foods. Nowadays, the modern-day Platonists have replaced this act with calorie counting and the shunning of high-calorie fatty foods.

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While Plato’s work provides no solution to the conflict, an understanding of his past and impact on the future provides valuable insight into how strong beliefs and the current dietary dogma has come into existence. Furthermore, it provides insight into why nearly every discussion on a healthy lifestyle and diet, and their implications for preventing cancer, must include at least a consideration of Platonic philosophy.

So, what does all this rambling have to do with food and cancer?

I sat there eating this delicious pecorino cheese made from unpasteurized sheep’s milk while drinking a local earthy Southern Italian red wine. Such a meal was the perfect combination as I went through the final touches on our manuscript Meat, eggs, full-fat dairy, and nutritional boogeymen: Does the way in which animals are raised affect health differently in humans?.⁴ The modern Platonists, Pythagorians, calorie counters, and those who consider the mantra “eat less, exercise more” to be dietary recommendations passed down from the Almighty himself will likely shriek at this paper. To them, all fats are the same – and more often than naught all fats will kill you – so we sought out to review the available literature to see how incorrect this mindset is when considering those same calorically-dense foods that Pythagoras shunned as they were made from animals, and Plato eschewed due to their opsa and richness (a.k.a. fat content).

Dietary recommendations for cancer prevention remain incredibly inconsistent with both each other and the available data. We originally pointed this out in our research paper around 8 years ago, and little has changed since then.⁵ The bulk of anticancer dietary recommendations continue to repeat the antifat religious-like message and grain-fed sacred cows that have been around for decades. These overweight sacred cows cling onto preconceived notions supported with a mixture of “expert” consensus and poorly done epidemiologic studies.⁶ However, this ball got rolling when Sir Richard Doll – the same Doll that linked smoking and cancer⁷ – found an association between breast cancer and dietary fat. Doll cautioned that these links may have been explained by wealth and a western lifestyle, but these warnings were largely ignored.⁸ Instead, a natural progression led to the attempts to link other lifestyle behaviors and dietary fat with cancer risk.

Several decades later, dietary recommendations remain in the dark ages, and dietary studies leave us all confused as they repeatedly contradict each other. For instance, dietary fat was linked to colon cancer in a handful of population studies, while the opposite may be true with breast cancer. Adding even more confusion, when carbs replace dietary fat, the risk of cancer rises.^5–7 Fruits and vegetables have remained the backbone of our recommendations, and even their support is shaky at best.¹² Some of the vegetable studies have hinted at benefits with specific vegetables, as opposed to the general recommendation of increasing fruits and vegetables together.

Could the benefits of dietary fat be linked to specific fatty foods, and could these foods be dependent on how the animals that made them were raised?

We set out to answer this question based on the available studies by assessing whether raising animals more appropriately could lead to improvements in human health markers after consumption of the animals or their eggs or dairy products. In other words, is it misguided to lump those demonized foods together as one? We systematically assessed the following factors that have been shown to affect cancer risk and prevention:

Omega-3 Fatty Acids in Meat, Dairy, Eggs, and Cancer

Omega-3 (n-3) Fatty Acids may make up a small proportion of fat in most diets, however, this small proportion pales in comparison to their importance in preventing cancer. They make up part of the protective layer around our cells, known as the cellular membrane, and help the brain and heart to function properly.¹³ Generally known as anti-inflammatory, they reduce several cytokines, while supporting our cardiovascular system and reducing triglycerides.^14,15 A lower amount of omega-3s and a higher amount of omega-6s within the diet and body can lead to inflammation, and is associated with an increased risk of several cancers.¹⁶ Furthermore, omega-3s compete with more inflammatory omega-6s to reduce inflammatory compounds and eicosanoids, like prostaglandin and COX-2. It is not surprising that the consumption of foods high in omega-3 fatty acids, like fish, is associated with lower rates of several diseases¹⁷ like cancer.^14,18

Conjugated Linoleic Acid in Meat, Dairy, Eggs, and Cancer

Much like omega-3s, conjugated linoleic acid, or CLA, is an anti-inflammatory fat. CLA is a 18-carbon fatty acid converted by bacteria in the gut of cows and ruminants from linoleic acids in foliage.¹⁹ CLA may positively affect several processes in early studies, including blood pressure, metabolism, atherosclerosis, and cholesterol, and can support the immune system and potentially combat cancer.^{19,20,21,22,23} The strongest support of CLA may be in its enhancement of fat metabolism and improvements in insulin sensitivity.^24–26 Perhaps most importantly, animal studies have shown that CLA helps to block many processes that can favor the development of cancer, like erratic cell cycling, cellular proliferation, and the production of blood vessels, known as angiogenesis.²⁷ CLA increases apoptosis, or the programmed death of cells that may be abnormal, and has been shown to be a weapon against breast cancer in animal studies.^{28–31,32,33–35} Foods containing large amounts of CLA, like certain delicious butters, may decrease the rate of tumors in animals.^19,25 Studies are limited in humans, but some have shown that higher levels of CLA in the blood are associated with lower risks of breast cancer.³⁷

Various research studies confirm the different effects animals raised on pasture diets can have on their carcasses and milk as opposed to stuffing them with grains. We know that pasture-raised animal products contain more nutrients like CLA and omega-3 fatty acids within their meat and milk, but does it make a difference after we eat them?^38,39

We can forgive Plato for his scientific ignorance, as it was well over 2,000 years ago and his methods were crude. Now that we have advanced technologically, we know that several dietary fats may improve markers that can impact cancer risk. As opposed to the menagerie of dietary recommendations given to cancer patients,⁴⁰ our paper assessed multiple factors that have been shown to modify cancer risk, including:

1. Conjugated linoleic acid (CLA)
2. Omega-3 fatty acids
   1. Alpha linoleic acid (ALA)
   2. Docosahexaenoic acid (DHA)
   3. Eicosapentaenoic acid (EPA)
3. Inflammatory factors
   1. Triacyl glycerol (TAG)
   2. Interleukin-6 (IL-6)
   3. Interleukin-8 (IL8)
   4. Tumor necrosis factor (TNF)
   5. C-reactive protein (CRP)

We also included the effect, if any, on serum cholesterol levels, not because they correlate well with cancer risk (they don’t)⁴¹, but rather because any discussion on dietary fat more often than naught devolves into an asinine discussion of cholesterol. We found, as you can see below in the table (and note: all tables used here are for noncommercial purposes and are approved by the authors, well, me), that after the consumption of butter, cheese, multiple dairy products, or beef and red meat from grass-fed animals, serum CLA rose, while several inflammatory markers decreased with grass-fed beef and game meat.

Eggs, with their “dreaded” cholesterol-laden yolks, seemed to fare even better. Eggs containing high amounts of omega-3 fatty acids increased the omega-3 fatty acids present within the blood of those humans that consumed them. Grass-fed beef had a similar effect, as did cheese made from the milk of grass-fed cows. This may seem obvious as you read this, but you would be surprised to hear that there has been significant opposition to the thought that the same foods from animals raised differently could have different biologic effects in humans.

My favorite study by far was that of Sofi and his team, not just for the results, but for the study methods. He provided 10 participants a weekly supply of 200g of pecorino cheese versus a commercially available cow cheese. Both groups ate the cheeses for 10 weeks each, and while both ate a food that would be assessed as the same via population studies using an antiquated food frequency questionnaire (yes Walter Willett, I am talking to you), the differences were significant.⁴² Pecorino cheese, the traditional Italian cheese that hails from Leonardo (who was a shepherd) and Pythagoras’ old stomping grounds, is made from the milk of sheep that graze on grass and is naturally rich in CLA. Subjects within the pecorino group watched their health improve as their lab values revealed significant decreases in the inflammatory factors IL-6, IL-8, TNF-α, and vascular endothelial factor (VEGF). VEGF is a growth factor that cancer cells rely on as it increases the development of blood vessels, links inflammation and cancer, and is key in the initiation of cancer.^43,44

The largely condoned fatty cheese that I enjoyed while writing the research paper was improving my health by decreasing inflammation and its association with cancer. It appears the butter that I used to cook my morning eggs, which are also from chickens that roam the pasture, were providing me with similar health benefits as well. Leonardo Pesce would be proud that the sheep from his hometown were potentially helping to lower our risk of cancer. Looking deeply into a recent large randomized trial, similar metabolic benefits were seen when individuals stopped counting calories and instead focused on real, wholesome foods⁴⁵ (see the graphic below). It is clear from the available studies: food is not a mathematical equation and we need to stop focusing on how much we eat, and instead focus more on what we eat, and what we eat eats. While Pythagoras may have provided us with some useful mathematical equations allowing us to pass our geometry exams, we are in a new era and it is time to begin treating food as food and leave the calculations to mathematicians.

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