The recent popularity of the bold documentary, Forks Over Knives, as well as a handful of some national best-selling books, has forced me to finally address the issue of vegetarianism in this blog. In my 16 years as a practicing nutritional consultant, I have been fairly clear with my clients on this issue: humans, by nature, are omnivorous creatures. I will summarize the facts supporting this assertion as well as confront the conclusions promoted by filmmakers, authors, and practicing vegetarians.
It is true that some humans (and by “some,” I mean a very small percentage) can survive and even thrive on a vegetarian diet. Because if there is one thing I have learned in my experience as a health professional, as well as a human being, it is that there are no absolutes. We are each biochemically unique and what works for one individual does not necessarily work for another. The key to determining what works for you is to learn to listen to your body and become aware of the signals it is sending you all day long (especially when you eat) about what is helping you and what is hurting you.
That being said, I do not feel the same way about veganism. While both vegetarians and vegans eat a plant-based diet, the former do eat some animal-based foods, such as fish and dairy products. Vegans, on the other hand, avoid all animal-based foods and, as explained later, I think this is a dangerous idea for 99.9% of the people.
There are many reasons people advocate vegetarianism. The prevailing theory seems to be that eating meat and animal-based foods promotes heart disease and cancer so we should avoid these foods. Another theory is that eating meat is inhumane because of the conditions under which livestock are raised and treated. And yet another theory is that the meat industry is harmful to the environment.
There are various arguments used to support these theories and I will address the most popular ones here. Suffice it to say, these are extremely complex issues and each warrants careful consideration. If nothing else, this article will give you “food for thought” (so to speak) so that you can perhaps ask your own questions and do some of your own research on the topic. Ultimately, my hope is that I can help you make a more informed decision about what is best for you. So let’s get into it!
Do Animal-Based Foods Promote Heart Disease and Cancer?
The biggest problem with this claim is that heart disease and cancer are primarily 20th century diseases and humans have been eating meat and animal-based foods for thousands of years. Prior to the turn of the century, the leading causes of death were pneumonia and influenza followed by tuberculosis and diarrhea—mostly communicable diseases.
As for the 20th century and beyond, there is no reliable scientific or even statistical evidence to support the blanket assertion that animal-based foods cause heart disease and cancer. First of all, since 1800 our sugar consumption has increased nearly tenfold and it is now widely known that sugar feeds cancer cells. Besides, there are many different types of cancer and the prevalence of these types tends to vary depending on geography and culture. While some omnivore-based cultures have higher rates of breast and prostate cancers, some vegetarian cultures have higher rates of skin and stomach cancers.
As for heart disease, the study most frequently referenced as a basis for this theory is the Framingham Heart Study of 1948, which followed 6,000 over several years and compared the health and mortality rates of subjects who consumed low amounts of dietary cholesterol and fat to those who consumed higher amounts. This study showed that those who weighed more and had higher blood cholesterol were more at risk for heart disease.
The problem is the Framingham study failed to make a connection between dietary cholesterol and serum (blood level) cholesterol. To the contrary, the subjects in this study who consumed more saturated fat and cholesterol not only had lower levels of serum cholesterol, they tended to weigh less and were more physically active. How could this be? Because we now know that the liver produces most (75%) of our serum cholesterol and a diet higher in refined carbohydrates (flour-based, starchy carbs) and lower in naturally occurring dietary fats causes the liver to produce higher amounts of the LDL (“bad”) cholesterol. We also know that some dietary fat is essential for basic metabolic functions, like hormone production and brain function.
To complicate this issue further, more recent research suggests that higher serum cholesterol isn’t linked to heart disease at all. In fact, half the people who die from heart disease have “normal” levels of blood cholesterol. For more on this, see my previous blog on The Real Cause of Heart Disease.
Possibly the most convincing evidence that humans were designed to eat meat is our physiology. Our stomachs produce hydrochloric acid (HCL), which is necessary to break down meat protein. HCL is not found in herbivores. Our pancreas also produces a variety of digestive enzymes for all kinds of foods, both animal and vegetable based. Additionally, our digestive tract is shorter than herbivore species and we only have one stomach, unlike most herbivores. At the same time, our intestines are longer than pure carnivores, which suggests that we are omnivores, much like our closest cousins the chimpanzees.
The China Study
The more recent study often cited to support the theory that meat-based diets cause disease, such as cancer, is The China Study, which is summarized in the book of the same name by Dr. Colin Campbell, and also featured prominently in the movie, Forks Over Knives. This is very large study of over 6,500 people in 65 different counties in China. It measured hundreds of variables in blood tests, diet and lifestyle factors, food intake, disease and mortality rates, and geographic factors. It was a very comprehensive study.
The problem is the way it was presented in the book and the movie is not accurately supported by the data. In fact, in many cases the data do not show a correlation between animal protein consumption and disease such as cancer at all. This data actually supports a stronger correlation between sugar and carbohydrate consumption and cancer. Since The China Study was published, there have been numerous critiques published about the inconsistencies between the conclusions reached by the scientists and the actual data. Given the extent to which this subject has been covered and can be found with a simple Internet search, I will not spend any more time with it here. However, if you want to begin your own in depth look at the data, you can begin with the book, Diet, Lifestyle, and Mortality in China, which dissects the study ad nauseum and, in many cases, contradicts the conclusions in Dr. Campbell’s book.
In addition to conflicting with much of the data in this study, Dr. Campbell’s conclusions conflict with the much larger body of studies that can be found on PubMed.org, which is an official database of the National Institutes of Health (NIH). Many of the studies found there and elsewhere online show that the healthiest people in Europe are inhabitants of Iceland , Switzerland, and Scandinavia who eat meat-based diets. Likewise, the Inuits (Eskimos) and indigenous peoples from some African countries eat diets very high in animal protein and fat and have very low levels of blood cholesterol and even lower rates of heart disease (the Inuits having virtually no heart disease at all). The point here is that different cultures are designed and have been conditioned throughout generations of evolution to thrive on different diets. So comparing an American diet to an Asian diet is hardly fair or useful.
The Wartime Norway Study
Another study cited in the Forks Over Knives film is the Norway study, which was more of an observation than a study. The focus here was on the rates of heart disease during the period between 1939 and 1945 when the Nazis occupied Norway and confiscated all of the livestock to supply food for their troops. Sure enough, heart disease dropped dramatically during this period and Dr. Caldwell Esselstyn, a vegan doctor, asserts that the reason for the drop is because the Norwegians were forced to switch to a plant-based diet.
What Dr. Esselstyn neglects to point out is that when the livestock was taken away, the Norwegians replaced it with lots of fish. Yes, they also ate more vegetables, which is a good thing, but their consumption of omega-3-rich fish increased by more than 200%! And as we now know, omega-3 fatty acids are very beneficial for heart health. Not only that, but during the same period they cut their sugar consumption in half and decreased their consumption of trans-fatty-rich margarine significantly. These would seem to be pretty important factors in a study about heart disease. Amazing what a few extrapolated facts can do for an agenda.
More of What They Don’t Tell You
Another glaring problem with Forks Over Knives is what it leaves out. The “real patient” subjects it uses as testimonials to its claims aren’t testimonials for vegetarianism as much as they are for a whole food based diet. The example that sticks out most for me is the guy who was taking a virtual pharmacy full of medications for heart disease, diabetes, and hypertension. He admittedly lived most of his life on highly processed and fast food diet with essentially no exercise. He went to see a naturopathic physician who eliminated all processed foods and junk food from his diet and instructed him to eat an exclusively whole food, plant-based diet. He was also instructed to exercise regularly. Within months the man lost several pounds and was able to eliminate all of his medications. He had completely changed his lifestyle and his state of health. It was truly an inspiring story.
However, the conclusion drawn by the filmmaker from this example was that the man was on a meatless diet and that is the sole reason for the dramatic improvement in his state of health. That’s quite a leap in logic. If you take anyone who eats primarily processed, fast food and put them on a whole food-based diet consisting of mostly fresh, unprocessed foods and get them to exercise daily, their health will improve, regardless of whether they include meat as part of the new diet. I have been doing precisely that with my clients for the last 16 years and I have seen similar results in those who follow these recommendations. The key is less processed food and more whole food. Meat is no less whole food than vegetables.
Another seemingly intentional omission in this particular movie was that it cited the lower rates of certain kinds of cancer—primarily prostate and breast—in the Asian and Indian cultures, but failed to mention that these cultures have higher rates of stomach and liver cancers. This is such a blatant example of taking data out of context and using it to support their agenda.
Another target that is often cited by vegetarians as a culprit in disease is milk, specifically cow’s milk. One study used in the Forks Over Knives movie is the casein- animal study where they fed one group of rats a diet consisting of 20% casein and another group a 5% casein diet. Casein is one of two types of protein found in cow’s milk. The rats that were fed the 20% casein diet had higher rates of cancer than the rats on the 5% casein diet.
What they left out was that the rats on the higher casein diet actually lived longer than the lower-casein rats. So the rats eating less casein may not have had liver cancer, but they died prematurely of other liver disorders such as a fatty liver, liver necrosis (cell death), and bile duct dysfunction. In fact, this famous rat study was actually published in two parts. Dr. Campbell chose to focus on the part that supported his conclusion. You can read a more detailed review of the full study here.
Yet another problem with the casein study is that it is not a fair representation of a typical animal-based diet—certainly not one I would recommend. You see casein makes up 80% of the protein in cow’s milk and has long been considered a mucus-forming, inefficient, and arguably carcinogenic form of protein. Conversely, whey protein—the other 20% of cow’s milk protein—is considered to be a higher quality, more bioavailable form of protein.
So why did the researchers choose to use the inferior casein protein in its study? Not to mention that chances are the casein was taken from pasteurized cow’s milk. The pasteurization process denatures the proteins and renders them virtually unusable by the human body, which means they are more likely to promote disease conditions. I have never promoted pasteurized milk as an acceptable source of dietary protein. However, I do promote raw milk, yogurt, and cheeses as good sources of protein.
Click here for Part 2 of this article where I address the issues around milk, the environmental impact of the meat industry, and the downsides of vegetarianism.