By Dr. Mercola
An estimated 6 million Americans are vegans, which is typically considered to be a healthy choice. However, there are drawbacks to strict veganism that need careful consideration.
Mara Kahn, author of "Vegan Betrayal: Love, Lies, and Hunger in a Plants-Only World," delves deep into the history and science of veganism, revealing many oft-ignored facts about this strictly plant-based diet.
She’s put together a compelling story, covering her personal journey from being a vegan and vegetarian to exploring diet and health and finding out the truth behind the hype. It’s really the best book I’ve ever read on this topic, as it covers the vegan issues in their entirety.
"Even though my book is titled 'Vegan Betrayal,' I do respect vegans and what they’re trying to do. My own journey led me back to vegetarianism. I know that many … vegetarians that became vegans … are suffering from diminished strength and faltering health.
I think this is a topic which has been swept under the rug and it’s not being openly discussed in the vegan community. I think it’s very important that we start this discussion. I hope this book will help kick-start that really important dialogue,” Kahn says.
Veganism Has No Historical Support for Its Health Claims
While I would never argue with anyone who decides to be a vegan for philosophical, spiritual or ethical reasons, I believe it's important to consider and address the risks if you're jumping into veganism for its purported health benefits alone.
Surveys show ethical considerations are the primary reason people convert to vegetarianism or veganism. But as Kahn reveals in her book, veganism is not the only ethical diet. She also presents compelling arguments that it's not a historically validated diet.
Kahn became a vegetarian at age 19, while traveling in Europe. She became an overnight convert after meeting a young vegan woman who Kahn refers to as “a beautiful specimen of humanity” and “extremely healthy” — not realizing this same woman would return to eating meat just five years later due to fading energy.
Up to that time, Kahn had eaten a very meat-based American-style diet, including bacon and hamburgers. At that time, in the 1970s, veganism was largely unheard of. It didn't get a strong hold in the U.S. until the 1980s.
Interestingly enough, Kahn’s investigation reveals there doesn’t appear to be a single cultural group in the history of the world who actually survived long-term on an exclusively plant-based diet. So from a health perspective, there’s very little historical support for the strict veganism idealized today.
"I did a thorough research of the history of vegetarianism. In fact, I spent almost six years researching this book. I'm a journalist … I love to dig deep," Kahn says.
"At this point, it's really important that we distinguish between vegetarianism and veganism. Vegetarianism has a very long and honorable history. It goes back at least 2,500 years to Greece, and much further than that in the Indus Valley, India and that part of the world.
It has proven itself to be a viable diet … [Yet even] in the Northern parts of India, the Kashmir regions, they eat meat because the climate is so different in the mountainous regions of North India.
Vegetarianism has a very long and noble history with verified health results. However, veganism … is a non-historical diet … Its health benefits are not verified.
There were scattered enclaves of religious people that lived cloistered lives who probably did follow a vegan diet … but these were very, very tiny populations, and we have no idea if they were healthy and how long they lived.”
There Are Short-Term Benefits to Veganism, but Long-Term Risks
From a historical perspective, veganism is a very recent development. The roots of veganism go back to England, when in 1944, Donald Watson coined the term “vegan.” Watson’s primary argument for veganism was one of ethics. At the age of 14, he’d witnessed the slaughter of a pig, which left him horrified.
Immediately, he decided to stop eating meat and wanted the whole world to follow suit, despite having no training in nutrition. Veganism is based on ideology, not human physiology, Kahn reminds us in her book, which also delves into human evolution.
Part of the confusion is that many vegans appear quite healthy in the earlier stages. This isn't so surprising when you consider the fact that many switch from processed foods to a mostly raw plant-based diet. The influx of live foods will undoubtedly improve your health.
However, in the long term, the absence of all animal-based foods can take a toll, as certain nutrients cannot be obtained from the plant kingdom. Carnosine, carnitine, taurine, retinol, vitamin D3, conjugated linoleic acid and long-chained omega-3 fats are examples. B12 deficiency is also very common among vegans.
After six or seven years, the B12 stored in your liver will be completely exhausted, at which point you may start to experience serious neurodegenerative diseases. There are many documented cases of blindness from B12 deficiency, as well as other neurological disorders.
Historically, Vegetarianism Always Included Some Animal Foods
Vegetarianism typically allows both dairy and eggs. Back in Pythagoras’ days, early Western vegetarians also ate fish. (Today, this “branch” of vegetarianism is sometimes separated out and referred to as pescetarianism.)
My passion has been identifying food to optimize health and I'm absolutely convinced that seafood is one of the healthiest foods on the planet, primarily because of its docosahexaenoic acid (DHA) content — a 22-carbon omega-3 fat that is absolutely essential for your health, as it's a structural component of your cell membranes.
If you have low DHA levels, it's almost physiologically impossible to be healthy because it's such an important part of energy generation at the molecular level. You need DHA, which is only found in fatty fish and certain other marine animals like krill.
There's even quantum physics going on with respect to its ability to capture light and integrate it into your system. For example, DHA in your retinal pigmented epithelium is responsible for converting sunlight into vital DC electric current your body needs. If you're deficient, your ability to generate energy by your mitochondria will be impaired.
Granted, water pollution is a major concern today, so you have to eat really low on the food chain. Anchovies, sardines, herring, wild Alaskan salmon, fish roe and krill are all good choices as they're high in omega-3s while being low in mercury and other pollutants.
Like It or Not, You Need Marine-Based DHA
If you exclude these foods, you're just not going to be healthy. And contrary to popular belief, you simply cannot obtain all the DHA you need from plant sources. Plant-based omega-3 (alpha-linolenic acid or ALA) has 18 carbons whereas marine-based omega-3s (DHA and eicosapentaenoic acid or EPA) have 22 and 20 respectively. The difference in the length of the carbon chain makes a significant difference in terms of functionality.
ALA functions as a source of fuel (food), whereas EPA and DHA are structural elements. More than 90 percent of the omega-3 fat found in your brain tissue is DHA, which suggests how important it is for healthy neurological function, for example.
The problem is that, although your body can convert some of the ALA found in plants to the DHA found in marine oils, it is very rare for it to be more than 5 percent — the typical conversion rate is 1 to 3 percent, or even less.1 This simply isn't enough to have any significant benefit.
So please, don't make the mistake of thinking you can forgo marine-sourced DHA for a plant-based ALA found in flaxseed, flaxseed oil, chia seeds, walnuts and leafy greens.
Adding Fish Can Make a Big Difference
I think one of the reasons why vegetarians — at least those who follow Pythagoras' model, which includes fish — seem so healthy is because this diet is lower in protein than the conventional meat-based diet. When you eat excessive protein, you stimulate powerful biochemical pathways that trigger disease. This, combined with the fact that fish provides critical omega-3 and other healthy fats and cofactors, makes a strong case for the "pescetarian" form of vegetarianism.
“I agree totally,” Kahn says. “I remember trying to be an omnivore again … I started eating plenty of fish and my health skyrocketed almost immediately … My energy just skyrocketed. I started sleeping better. My nerves became calm. I was in intense gratitude to this first [wild salmon] that I ate; for the energy and the renewed love for life that it bestowed on me. It was absolutely amazing.
I did interviews and talked to or heard the stories of hundreds of vegans and ex-vegans, and almost invariably … the same thing happened to them … I think there's a very good reason Pythagoras ate some fish from time to time. It was plentiful in the Mediterranean region where he lived. It wasn't contaminated. There's reason he prescribed it to his everyday followers in the towns. That reason is probably DHA …
DHA is really a problem with vegans … In fact, two of the founders of veganism, as they became older, suffered from Parkinson’s disease. They had their DHA tested and it was zero … I eat sardines every other day. The rush of powerful and sustained energy I get from them I cannot find anywhere in the plant world.”
Low Protein and Low Fat — 2 Common Health Barriers for Vegans
While keeping your protein low is a wise move, excessively low protein can become a problem for vegans — especially if your diet is also low in healthy fats. Some will get just 8 to 12 percent protein from plants in their daily diet, which can trigger muscle wasting. "In that sense, vegans are consuming flesh after all — their own — if they're not eating enough protein," Kahn says.
Low fat is another, and in my view, more concerning problem, among vegans. When you eat a high-net carb diet (total carbs minus fiber), you're essentially burning carbohydrates as your primary fuel. If you shift down to relatively low levels of net carbs, which is easy to do on a vegetarian diet since vegetables are so high in fiber, then your body starts burning fat as its primary fuel. This means you need to increase the amount of healthy fats in your diet in order to satisfy your body's fuel demands.
Sufficient dietary fat is also essential for maintaining healthy hormone levels, Kahn notes, including your sex hormones. Raw veganism in particular is associated with loss of menses (amenorrhea), due to low calorie and fat intake, increasing your risk for infertility and osteoporosis.
Low fat is likely far more troublesome than low protein, because once you start burning fat for fuel, powerful protein-sparing processes start taking place, allowing you to get by with as little as 6 to 8 percent protein without risking muscle wasting. I only have 8 percent protein in my diet and I do not believe I'm protein deficient. That's because fat is my primary fuel. If I were burning carbs, I would not fare well at all with such a low amount of protein.
Veganism Has a High Drop Out Rate
The health problems associated with veganism create a high dropout rate. It's difficult to find good statistics on this, as people don't want to discuss it. Many are ashamed, feeling they've somehow "failed," and many are shamed by their fellow vegans, who believe they're making a huge mistake to go back to eating animal foods.
"I've even read accounts of ex-vegans who describe it as kind of cult-ish. The shaming that ensues is very powerful … One vegan told me that when she decided to go and buy some eggs for the first time in, I don't know, 10 or 15 years … her boyfriend, who was a staunch vegan, refused to go in with her. In fact, he had told her … he would rather she was a continually suffering vegan than to be a healthy meat-eater.
This, to me, was a perfect illustration of what I personally call Reverse Speciesism, preferring the health of an animal over the health of your fellow human being, which is really kind of a new thing, I think, in human history. It's not talked about much in the vegan community — the high dropout rate — but the numbers are large … It's estimated about 50 percent of vegans have left because of declining strength and declining health."
Even Vegan Diet Affects Animals
What many vegans fail to integrate into their overall evaluation is that even the consumption of an exclusively plant-based diet involves killing a wide variety of animals. Not intentionally, of course, but rather as an artifact of the process of growing the food. Essentially, there's no animal-free lunch, which is a direct quote from Kahn's book. There's going to be some type of destruction of life involved. Then there's the issue of plant consciousness as well.
As noted by Kahn, unless you're growing all your food by yourself in a no-till organic setting using hand tools, animals are destroyed in industrial agriculture. Studies by reputable scientists show up to 70 percent of rodents and small animals present in industrial growing fields end up being killed by the machinery. Animals are also killed in traps, and during food storage and transportation. As Kahn says:
"To be a vegan, you have to somewhere draw the line on what food you will eat and what you won't. For most of them, it's a matter of consciousness. Is the living thing conscious of what's going on? Is it suffering? That demarcation between an animal that's conscious and unconscious has totally changed throughout history and throughout cultures.
For instance, now they're looking at fish. In the past, it was just decided, because they were so cold looking and expressionless, that fish didn't have consciousness. But new testing is showing that perhaps they do; perhaps they can feel pain … People are taking that further and looking at insects. I interviewed scientists that work with insects. Some of them really do believe that insects have consciousness and an intelligence that we can't even understand …
The same with plants … Brilliant botanists believe that plants have elevated intelligence that we can't even begin to understand, because we don't speak the same 'language.' They know for sure that plants absolutely know when they are being eaten.
Living plants send out chemicals to warn their neighbors of danger ahead and they send out chemicals that summon insect bodyguards to ward off predators. These are intelligent beings that want to live. They have what I call 'want to live, don't want to die' skills that are very developed."
It's also worth noting that some of the research vegans rely on to substantiate their dietary choices as healthy actually do not offer such proof. For example, when Kahn dug deep into some of the most well-known studies that vegans love to cite, she discovered they actually define vegetarianism in a very broad way. They do not support a purely plant-based (vegan) diet at all. Not only did these studies include fish-eaters, but also dairy-eaters and even those who ate red meat once a week.
Why the American Dietetic Association Now Promotes Plant-Based Diet
Kahn says to be very wary of vegan studies conducted by vegans. As with all conflicts of interest, people have a tendency to find what they want to find, even if they have to massage the data a bit to get there. Interestingly, in recent years the Academy of Nutrition and Dietetics (AND), formerly the American Dietetic Association (ADA), made the transition to promoting a plant-based diet. As it turns out, this decision was primarily based on the recommendations of a devoted vegan and a vegetarian.
“The ADA position paper, which came out in 2009, recommends a vegetarian and a vegan diet to all people of all ages, from infancy to old age. If you do some more digging, as journalists love to do, [you find] it was co-authored by two people. One was a vegetarian and one was a vegan. In fact, the vegetarian belongs to a religious denomination that encourages the spreading of vegetarianism across the world.
My question is: why weren’t these two authors tagged for conflict of interest? They’re recommending this to the whole world and to all ages …
There are some serious flaws in their research. First of all, I looked at their sources. I can't remember if it was 100 or 200 sources. I could find only 17 in all those sources that were exclusive to vegans. You cannot take vegetarian research and apply it to vegans. It just doesn't work. There are too many missing nutrients in a vegan diet that are present in a vegetarian diet.
I wish that vegans would not just read vegan blogs and websites and recommendations from other vegans. They need to look at science, at research — non-biased sources. They need to read my book, which would tell them everything they want to know about the history, philosophy and nutritional facts of veganism.”
That's not an inflated claim, I can assure you. I've read hundreds of health books, and Kahn's book, "Vegan Betrayal," is among the very best when it comes to teasing out the truth about veganism and health.
Balance Ethics and Health When Choosing Your Diet
I'm not opposed to vegetarianism. By Pythagoras' definition, I am a vegetarian. I eat very small amounts of animal protein; mostly fish. Occasionally, I'll have some organic grass-fed meat or free-range pastured chicken. But meats are not a cornerstone staple in my diet, and I believe most people could benefit from lowering their meat consumption. It shouldn't be entirely excluded, however, because animal foods do contain very valuable nutrients your body needs for optimal health.
Organic pastured eggs are another source of incredibly healthy nutrients. Ditto for raw butter. If ethics and animal welfare are your concerns, I would encourage you to investigate and educate yourself on humanely-raised animal foods.
Yes, the animal will die in the end, but there's a tremendous difference between the life of an animal raised in a concentrated animal feeding operation (CAFO) and one raised on pasture that is allowed to live a full, healthy and stress-free life. There's also a big difference in the way they're slaughtered.
At the end of the day, you have to choose between the life of an animal somewhere — even if only a few rodents caught in a harvester — or your own health. A balance must be struck between optimizing your health and causing the least amount of unnecessary suffering.
“If you look at the most lauded diet in the world, the Mediterranean diet — which by the way, they were doing a long-term study on, and which they ended early in 2013 because the benefits were so enormous they felt it was unethical to deprive the control group — the Mediterranean diet, which is mostly plants, limited fish, limited red meat, limited dairy, [gives you] all the carni-nutrients you need … It’s a complete diet.
It's been named one of the best diets in the world. It's historically validated for thousands of years and many, many generations that this diet confers long lasting health and long life … The vegan diet is not validated. That's what we need to work on — getting those research studies done, so that future vegans will know what they're up against," Kahn says.