The Raw Truth About Vegan Diets

This article may bring me some heat, but busting down dogma in nutrition, and taking heat for it, is something I have been doing for decades, before there was an internet. Yes, there was a time before the internet, but I digress. Why am I writing this article? Because I have grown tired of rehashing the same information with dogmatic vegans who attempt to use the same false narratives and pseudo-science as their justification for recommending people go vegan. Vegetarians of the lacto-ovo variety seem to view being a vegetarian as a way of eating. Vegans however often approach it as more of a belief system, bordering on religion, and as with many of that ilk, don’t tend to let facts get in the way of their belief system. I’m supportive of any nutritional approach people wish to follow that they feel is best for their goals, but I loath dogma based on pseudo-science and demonstrably false claims such as “protein intakes above the RDA are bad for the kidneys” and “creatine has been shown to cause cancer” or the various “facts” some in the vegan community rely on to push an agenda. The goal of this article is to give people the facts, and let them make their own decisions.

I’m going to cover these topics in broad strokes, and leave it to the reader to follow up with the sources and links provided should they want to dive deeper into the details of each section. That’s the only way I can keep this article just short of text book length. In no particular order, these are some of the most common claims made by proponents of veganism:

“Humans Are Not Meant To Eat Meat”
This is in line with some claiming humans are naturally herbivores. There’s not a single evolutionary biologist, human anatomist, or respected human paleontologist, or major scientific group focused on human anatomy and physiology that view modern humans as anything but omnivores. There’s various claims of differences in teeth, or digestive systems, and so forth, of humans comparing us to other animals attempting to show we are herbivores, and they’re easily debunked. An excellent article examining that topic, is written by a vegan biologist HERE which covers the topic in great depth. To quote from the article:

“…trying to claim that humans are something else than omnivores are just counter productive since it’s quite easily debunked and we lose credibility. There are plenty of reasons to be vegan and still stick to what is true.”

We know that human ancestors were eating meat for at least two and half million years and one generally well accepted theory is we evolved into modern humans due in large part to our ancestors eating nutrient and calorie dense animal parts; meat, marrow, organ meats and so forth. How much animal flesh, marrow, or organ meats our ancestors ate varied greatly, dependent on geographical location, seasons, availability, and so forth. Claims that humans are not carnivores are correct! Humans are not carnivores, they’re omnivores, and our anatomy and physiology is quite clear on that one, and those vegetarian sources more interested in science – such as The Vegetarian Resource Group – agree with that assessment. (1). Humans are omnivores, the end. Of all the reasons offered by vegans as to why humans should not eat meat, I consider this one the lamest by far and it ends any credibility they may have.

Should We Eat Like Our Closest Relatives?
A logical segue from the last section is to address the common claim our closest relatives, the Chimpanzee, are herbivores and therefore we should follow their nutritional approach.

Why we should eat like our closest genetic relatives I don’t know, but let’s explore that one. It’s illogical on its face of course, but also false. The view of the sweet peaceful fruit eating chimp as who humans should emulate is misplaced. Chimps are hunters of animals, and highly aggressive hunters at that. While most of their food is plant based (fruit) to be sure, chimps are active hunters, and just like humans, will hunt an animal they eat, usually other monkeys, to virtual extinction if given the chance. When they run out of one species they like to eat, they start hunting others. (2) Yes, we humans and chimps have quite a bit in common, as chimps will form hunting parties, as well as start wars against other tribes, but that’s another topic for another day. In one location, chimps wiped out almost 90% of the Red Colobus monkey population due to over hunting. So yes, chimps are more like us than maybe most imagined, and not always in a good way. As one researcher put it:

“In their tendency to blindly over-hunt their prey, chimpanzees are rather similar to humans. Perhaps that’s not too surprising, as they are our closest living relatives.” (3)

Maybe it’s only chimps that do that? Nope. Their bonobo cousins are known to hunt and eat other mammals, including monkeys. DNA samples also suggest wild African western lowland gorillas do the same.

Health And Longevity
One primary claim of vegan proponents is that it’s superior way of eating for health and longevity. It’s true that some studies suggest heart-healthyvegans suffer less diseases that afflict western society vs omnivores, but it should be noted that’s not a consistent finding and suffers a number of problems. Most of these studies are population studies, and compare the Standard American Diet (SAD) to those who are vegetarians or vegans. That’s setting a mighty low bar as virtually any diet is better than SAD. On that, I think virtually everyone can agree. A number of problems arise from this type of research such as confounders. For example, Healthy User Bias and Upper-class Bias; It’s found people who follow meat-free diets are also more likely to engage exercising regularly, don’t smoke, and are from higher-income families, who tend to have better health already. Finally, a major problem in nutrition research is inaccuracies in reporting of the diet. What people report, and what they actually eat, can be very different. There’s also population studies that find vegans actually suffer higher rates of some diseases, but not others. The reality is, people cherry pick the studies that support their pre-existing beliefs, and ignore what ever triggers their cognitive dissonance. For example, some will point to population studies such as the long lived people of Okinawa vs the Japanese population at large. All well and good, but while the population of Okinawa is not vegan, they do eat a high percent of their calories from plant based sources compared to other populations compared. “Ah ha!” says vegan and vegetarian advocates. However, there’s a wrinkle they often miss, or actively overlook:

“In 1992 scientists at the Department of Community Health, Tokyo Metropolitan Institute of Gerontology, Japan published a paper which examined the relationship of nutritional status to further life expectancy and health status in the Japanese elderly. It was based on three epidemiological studies. In the first, nutrient intakes in ninety-four Japanese centenarians investigated between 1972 and 1973 showed a higher proportion of animal protein to total proteins than in contemporary average Japanese. The second demonstrated that high intakes of milk and fats and oils had favourable effects on ten-year survivorship in 422 urban residents aged sixty-nine to seventy-one. The survivors revealed a longitudinal increase in intakes of animal foods such as eggs, milk, fish and meat over the ten years. In the third study, nutrient intakes were compared between a sample from Okinawa Prefecture where life expectancies at birth and sixty-five were the longest in Japan, and a sample from Akita Prefecture where the life expectancies were much shorter. It found that the proportion of energy from proteins and fats were significantly higher in the former than in the latter. ” (4)

The point is, while population studies have their uses to be sure, they tend to suffer a variety of flaws as it applies to the application of nutrition in individuals per se and people need to read the finer details. This is not intended as a full review on this topic due to obvious space limitations, but it should be noted that the longest lived populations – while they do get most of their calories from a plant based diet – are not vegans. Can humans be perfectly healthy on a well-designed vegan diet? Yes! However, humans are highly adaptable omnivores and can survive eating damn near anything, but I’d posit that feeding any animal as its inherent physiology dictates, is likely to get the best results long term, as humans are not natural herbivores.

FYI, in case you’re wondering, the nutrition approach that is consistently associated with lowest rates of various common diseases, and fish-oil-salmonincreased longevity, is what’s generally referred to as The Mediterranean Diet. This diet includes, vegetables, fruits, fish and whole grains, nuts, healthy fats, with minimal, but does not eliminate, red meat. If people ask me what the data consistently suggests is the optimal approach to health and longevity, the Mediterranean Diet comes up a winner study after study. As this is not an article about the benefits of the Mediterranean Diet, I will leave it to readers to follow up on that one, but it’s in line with what I and others have been recommending for decades.

Side Bar: Longevity vs Sports Nutrition.
It should be noted, the optimal diet for health and longevity may not be the optimal diet for performance, or building muscle, and so forth. While the two are not mutually exclusive, they do appear to differ in some aspects and people should understand that what they eat to build muscle may not be what optimizes health and longevity per se. Obviously, one can strike a balance between them, but they should not be viewed as one and the same as a nutritional approach.

Nutrient Deficiencies In Vegan Diets
It’s well established that vegans regularly suffer from nutrient deficiencies, and most vegans will admit that. I’m not going to run down the list of deficiencies, as it does not really add to the discussion here, but a list does appear in the abstract posted in the latter sections. Of course proponents of the vegan approach will claim a “well-balanced” vegan diet and a few supplements will cover those nutrient deficiencies and point to the fact deficiencies are found in the general population of omnivores. They are correct on both points. However, per prior comment, comparing to SAD is a very low bar to set, and vegans must be extra diligent with their approach to assure they don’t suffer deficiencies. Can one be a vegan and not suffer nutrient deficiencies? Yes, but here’s a simple Q: who is less likely to suffer nutrient deficiencies; those who follow a well-designed vegan diet or those who follow a well-designed omnivore diet? One does need to be a scientist to figure out the answer to that Q…It should also be noted, over 80% vegetarians and vegans will go back to an omnivore approach, one reason being, difficulty of getting a balanced nutrient intake among other reasons listed. (5)

Psychological Disorders
It should be noted, which is usually ignored or intentionally overlooked I suspect, vegans and vegetarians are found to suffer from higher rates of psychological disorders compared to omnivores, and a number of studies have found that result. (6,7) Now, those studies also expose the flaws in such correlational population-based epi data as mentioned above. That is, cause and effect; as correlation does not always equal causation, nor should any be assumed no matter how tempting. Do the nutritional deficiencies in vegetarian and vegan diets some suffer cause increased rates of psychological disorders, or, are people with psychological disorders more likely to be vegetarians or vegans? Or, is it unrelated to either, or, a combination of both? The answer is unknown at this time, but it is something to at least be aware of. Is that a reason to not be a vegan (or vegetarian in this context)? That’s a personal judgement call I can’t make for people. Some people also report feeling better mentally and physically as vegans, but people should at least be aware of that data.

Advice For Vegan Athletes
What about athletes and active populations? Can people succeed in athletic endeavors as vegans? I suspect it depends to some degree on the type of athletic endeavor, but data is lacking. It’s surprising to me how little data actually exists looking at that topic, but “on paper” as they say, the answer should be yes. However, vegan athletes need to be that much more diligent to avoid and or address possible deficiencies. Luckily for us, an excellent review paper on that very topic was recently published, and I highly recommend anyone who is a vegan athlete, knows a vegan athlete, or is considering being one, read the full review paper. (8) Here’s the abstract from the review with the full paper linked in the sources section:

“With the growth of social media as a platform to share information, veganism is becoming more visible, and could be becoming more accepted in sports and in the health and fitness industry. However, to date, there appears to be a lack of literature that discusses how to manage vegan diets for athletic purposes. This article attempted to review literature in order to provide recommendations for how to construct a vegan diet for athletes and exercisers. While little data could be found in the sports nutrition literature specifically, it was revealed elsewhere that veganism creates challenges that need to be accounted for when designing a nutritious diet. This included the sufficiency of energy and protein; the adequacy of vitamin B12, iron, zinc, calcium, iodine and vitamin D; and the lack of the long-chain n-3 fatty acids EPA and DHA in most plant-based sources. However, via the strategic management of food and appropriate supplementation, it is the contention of this article that a nutritive vegan diet can be designed to achieve the dietary needs of most athletes satisfactorily. Further, it was suggested here that creatine and β-alanine supplementation might be of particular use to vegan athletes, owing to vegetarian diets promoting lower muscle creatine and lower muscle carnosine levels in consumers. Empirical research is needed to examine the effects of vegan diets in athletic populations however, especially if this movement grows in popularity, to ensure that the health and performance of athletic vegans is optimised in accordance with developments in sports nutrition knowledge.”

Be that as it may, I will again ask the simple question: Will a vegan athlete have greater difficulty avoiding nutrient deficiencies – which could have a negative impact in performance – compared to an athlete following a balanced omnivore diet? Again, one does not need to be a scientist to figure out the answer to that one… The paper gives solid advice for vegan athletes how to avoid nutrient deficiencies while optimizing performance via some supplements vegans may find very helpful.

Saving The Environment
Doing things that help to protect the environment is a noble thing, and important to be sure, but people often get mislead as to what will actually help the environment vs. what will harm it and take at face value what they were told, especially if it supports their own pre-existing views on the topic. Many are under the impression that eating less/no meat is good for the environment. While it’s a contentious topic, readers should be aware that’s not even close to being universally accepted and it’s worth reading counter-views to at least be aware it’s nowhere near to as cut and dry as some may think. For example, I recommend reading Sorry, But Giving Up on Meat Is Not Going to Save The Planet and Vegetarian And ‘Healthy’ Diets May Actually Be Worse For The Environment, Study Finds as places to begin researching that topic for non-scientists.

The Ethical Vegan
From the previous sections, people may have concluded I’m against vegan eating. That’s not the case at all, but per my life mission over the last three decades or so, I want people to make informed decisions, and go from there. Who should be a vegan? Those who have a moral, ethical, personal, or any religious reasons, for not eating animals, should be vegans. Those reasons are just as valid as any other in my view. I shall quote the vegan biologist again:

“As a vegan, I strongly hold the position that killing and using animals for human gains is wrong. It’s wrong regardless of if it’s healthy or not. It’s wrong regardless of if it’s bad for the environment/climate or not.” (9)

“But wait, there’s more!” as the old commercials used to say to inspire people to impulsively purchase what ever they were selling. If that’s how you feel, that eating animals is morally and ethically wrong, and that’s why you have decided to be a vegan, then I say more power to you, but again, it’s not as simple as it may appear: If the goal is to reduce animal deaths due to human food consumption, various published papers suggest vegan eating may actually lead to a greater death toll of animal lives. Some have calculated that more animals are actually killed via the harvesting of the plants, and greater environmental damage done, and people need to be aware of that. See Ordering the vegetarian meal? There’s more animal blood on your hands for a discussion on that topic if interested. As expected, that and other papers that suggest being a vegan actually leads to more animals deaths vs less have been contested and challenged as to the methodology used and other variables (10) , but again, what people need to understand is, being a vegan is far from harmless to animals, and does come with large scale death to animals, be they cows or mice and birds.

Diving into the whole topic of whether it’s morally and ethically wrong for humans to eat animals is truly outside the scope of this article. However, whether I agree or not, those are valid reasons to be a vegan if you agree with the statement above, and I invite the reader to follow the link in the resources section for explore his thoughts on the topic in greater detail. Of all the reasons people decide to become vegans, the “ethical” vegan is the only one that carries any weight for me. Who knows, maybe I will conclude at some point I’m just not morally and ethically comfortable eating animals anymore myself and become a vegan. Stranger things have happened, but don’t hold your breath on that one. Still, I “get” why some don’t want to eat animals, or parts thereof, for their own personal reasons.

Per usual, the intent of this article is to assist people in making informed decisions based on science and objective reasoning, and allow them to journey on from there. I do feel that by consistently perpetuating bad science, pseudo-science, debunked claims, and mythology commonly based on emotions over facts, the vegan community is ultimately being counterproductive, perhaps reducing the number of people who decide to be vegans. If one becomes/became a vegan because they’re under the impression humans are not meant to eat meat, are naturally herbivores, or that studies all agree it’s the healthiest way to eat, and so forth, they’re misinformed. If that hurts peoples’ feelings, causes some cognitive dissonance* and angst for some, that can’t be helped. I’m not against vegan diets, I’m against the dogma and pseudo-science used by vegans to promote it. Science does not make allowances for our feelz, but it assists and direct us all to make informed objective decisions about what we eat; and other essential choices we make in life. This topic is should be no different.

Happy hunting… No pun intended!

(4) Shibata H., Nagai H., Haga H., Yasumura S., Suzuki T., Suyama Y. Nutrition for the Japanese elderly. Nutr & Health.