Vegan diets don't work. Here's why

Meatless diets are risky experiments.

The following is the transcript with links to sources for my recently uploaded video “Vegan diets don’t work. Here’s why”

In 1894, a Dentist was on a mission to solve a mystery that puzzled professionals for a while. Why were people’s teeth becoming so crooked? Dr. Weston A. Price set off on a 10 year journey traveling to 14 different countries in search of people who naturally had excellent teeth. He discovered something strange. How could crooked teeth be genetic when several parents with perfectly straight teeth had one child with very crooked teeth but another child with straight teeth? Also having straight teeth generally meant the rest of the face was more attractive. So, what made the difference?

Interest in plant based diets has exploded recently (S) with the number of American vegans and vegetarians going from 2.6 million in 1994 to 19.8 million in 2020 - a 7-fold increase.(S) Plant based food sales are expected to shoot up from $29billion to $162billion by 2030.(S)  But will cutting out animal foods really improve health?

If eating zero animal foods improves health so much, why would a 2016 study find that 84% of vegans eventually quit their diet?  

In this video, I’d like to tell you story behind why I think plant-based is not the best direction to head in. We’ll have to look at 

1. The rest of this puzzle on straight teeth

2. The specific consequences of removing animal foods from the diet

3. The story on why humans may be getting weaker, not stronger

4. Our rocky history of trying to create brand new fake foods

Paleoanthropologist Daniel Lieberman explains in his book The Evolution of the Human Head that "...jaws and faces do not grow to the same size that they used to...” For a very long time, it was the norm for humans to have large skulls and quite broad mouths. When the mouth, the dental arch, is too small… there’s not enough room for the teeth to come in so they crowd together and become crooked. 

Based on studies from 2009 to 2019, the prevalence of children developing crooked teeth is 53% in America, 56% worldwide and 72% in Europe.

So the question becomes: why would the dental arch grow big enough for this brother, but not for this brother?

That’s where Weston Price comes in. He was conducting his studies at a particular point in time where he could observe the changes new, modern foods were having on these peoples who had had straight teeth and great overall health. New processed foodstuffs like refined grains, sugar or vegetable oil were spreading and these people living in remote areas were finally getting access to them. He found a clear pattern - those living on their traditional diet were in good health and had broad dental arches, straight teeth and very few cavities. However, other groups in the same area who started eating these new modern foods developed crooked teeth and 5 to more than 30 times the cavities of their counterparts, despite having similar genetics. (Nutrition and Physical Degeneration)

Dr. Price wasn’t saying just that sugar, processed grains or vegetable fats were evil, but that they were displacing far more nutritious foods. The more modern foods people ate, the less room in their stomach for a highly nutritious traditional diet. Across all groups he studied; the foods they most prized were nutrient dense animal foods. From the people of the outer hebrides who ate cod heads and livers, to the eskimos who ate the various organs of large animals and the eggs of fish, or the people of New Guinea who ate dugongs, or the people of the Andean sierras who ate llamas and alpacas - Wherever he went, he found that these groups eating a traditional diet always prized some form of marine or animal foods and enjoyed robust skeletons, broad faces and resistance from infectious and chronic disease. Weston Price noted that these foods were particularly high in the vitamins A, D and K2 - providing allegedly ten times more than the average American diet (Nutrition and Physical Degeneration, Pg 247)

It’s well understood that each of these vitamins have many functions in the body, but what does this have to do with nice teeth or looking attractive? Well, research later confirmed that along with things like protein and calcium, these vitamins indeed work together to transport minerals to support  proper formation of the bones.(S) And of course your facial structure which includes the dental arch depends on proper development of your facial bones. 

Dr. Price noted full-fat dairy as one of the traditional foods many of these peoples considered valuable. So it’s interesting to observe that the Dutch are competing with Montenegrins for the tallest people in the world title (animation source: USA data) and they happen to be 2nd and 3rd on the list for the most milk consumed per capita in the world. According to Science Magazine “scientists assume that a diet rich in milk and meat played a major role” in the drastic increase in height of Japanese people living in Hawaii. A study of 105 countries in the journal Economics & Human Biology noted that animal food, particularly dairy, most correlated with increases in height. 

So why would it be hard to replace animal-derived vitamins with ones from plants? 

Well, I recently interviewed Yovana Mendoza who had essentially made a career based around her vegan lifestyle when she had health issues she tried her best to solve them while staying on the diet, using all kinds of supplements and troubleshooting strategies but she eventually had to prioritize her health and quit the diet after 6 years … even though she had every motivation to keep being vegan. Reintroducing animal foods fixed her health issues. Yovana’s case is a peak at how complex it can be to replace animal foods in your diet. To understand ths, let’s look at these 3 vitamins Dr. Weston Price was focused on:

Take Vitamin A - you might think the average vegan has way more vitamin A because it comes from vegetables like carrots or sweet potatoes - but that’s not vitamin A,  that’s beta carotene that has to be converted into vitamin A …and the conversion rate is very poor - about 12:1.(S) Though it’s more like 21:1 when you account for the hampering effect of fiber in the diet.(S) Not only that, the more you eat, the worse the conversion rate becomes.(S) Further, depending on your genes, your conversion rate could be even lower - this is the case for me… and for potentially as much as 37% of people of European descent.(See also, 57% lower) Actual vitamin A only comes from animal foods or synthetic supplements.

A 2021 study found vegan Finnish children had insufficient vitamin A and a 2020 German study found vegans to have a lower vitamin A level than omnivores. (S,S2) 

Vitamin D

Vitamin D is pretty much only found in animal foods with some exceptions like some mushrooms and some algae. Some people can get enough vitamin D from the sun, but if you live at latitudes above 37 degrees, your skin barely makes any vitamin D from the sun except for in summer. (S) 

A 2016 Finnish study found vegans’ levels of vitamin D to be 34% lower than omnivores(S)

Vitamin K2

Unless you’re eating fermented foods, you’ll only find vitamin K2 in animal foods. The richest sources of K2 are going to be animal livers (especially goose liver), egg-yolks, hard cheese and full-fat dairy. Unfortunately New York City made it illegal for schools to serve whole milk in 2006. (S2) The fermented soybean dish natto does in fact have a ton of K2 and sauerkraut has some too. Vitamin K2 helps put calcium into the right places like your bones and keeps it out of your heart which is thought to be one reason higher vitamin K2 strongly correlated with reduced risk of heart disease.(S,See also)

Speaking of all these nutrients for the skeleton, a 2021 polish study found vegan children to have weaker bones and were 3cm shorter than their meat eating counterparts.(S) A British study and a Dutch study also found vegan children to be shorter.(S,S2, See also) Of course other nutrients like high quality protein and calcium are factors in height, both of which vegans have to work harder to get enough of. 

Weston Price wrote in his 1939 book Nutrition and Physical Degeneration “As yet I have not found a single group of primitive racial stock which was building and maintaining excellent body by living entirely on plant foods.” Even Ghandi tried his hardest to be vegan, but eventually acknowledged that he at the very least needed to include dairy in his diet to prevent his health from deteriorating. In 1931 on a trip to France, he brought two goats with him to meet his daily milk requirement.

But that was decades ago, and since the arrival of the B12 supplement in 1947, people can now rely on supplements. There’s nothing stopping high tech foods like Beyond Meat from fortifying their product with nutrients that can be difficult for vegans to to get enough - things like B12, iron(S,S2,S3,S4), zinc(S,S2), selenium, iodine(S,S2,S3), calcium(S), omega-3’s(S), and Vitamins A(S),  & D(S,S2,S3). (*Also see: Rizzo, AHS-2 2013  ,  Davey, UK EPIC-Oxford, 2002  ,  Larsson, Sweden, 2002  ,  Haddad, United States 1999  ,  Draper et al., United Kingdom 1993  ,  Lockie, UK, 1985  ,  Ellis, Path, and Montegriffo, UK, 1970)

So why can’t we just look up all the components of meat and make a meat replacement?  

Let’s start by looking at at B12 as this component is near impossible to get just from whole plant foods. 

B12(S,S2)

Most vegans know they need to supplement B12 which is very important for proper brain function. Yet, one study looking at B12 status in vegetarians and vegans found that 7% of vegetarians and 52% of vegans were not getting enough B12. (S) However, in another study  with a more sensitive testing method - they found a whopping 77% of vegetarians and 92% of vegans had insufficient B12 whereas only 11% of omnivores did. (S) Perhaps these B12 supplements don’t work exactly like animal foods do. Also it can take years to deplete the body’s B12 store, so people can be lacking B12 for a while without realizing it

And, pregnancy increases women’s B12 requirement almost 3 times. When the mother is deficient in B12 the baby can have retarded growth, loss of neuromotor skills and permanent neuropsychiatric conditions.(S) Psychologist Kimberly Wilson says there are over 40 case reports of babies being hospitalized for severe B-12 deficiency after being breastfed by vegetarian/vegan mothers.(S) In two specific cases, one where the mother was taking a prenatal supplement and another where the mother had no symptoms of B12 deficiency, the babies still had neurological issues indicating severe B12 deficiency.(S,S) This highlights the need to check B12 status.

This isn’t to say it’s impossible to get enough B12 from supplements - perhaps some people simply need to take more or a different type. A B12 supplement may not work quite the same as animal derived B12, but another possibility is the vegan diet has impaired digestion.

So as mentioned 84% of vegans go eventually back to eating animal products… but to be fair, it’s for various reasons like social factors and practicality, however many do quit the diet because of health issues. Even people like Jon Venus, Alyse Parker, Bonny Rebecca, Cosmic Skeptic, Tim Shieff and others who achieved fame in part because they were vegan still could not make the diet work.  

And, each of these people experienced gut issues.

It’s understood that a variety of gut issues impair B12 absorption. There are various compounds in plants people can be sensitive to like gluten, oxalates, lectins and phytates, but simply eating too much fiber could be a culprit. A 2012 study found in 63 patients with constipation, reducing fiber intake improved symptoms but eating a zero fiber diet completely eliminated all symptoms. As for B12, you need to have strong enough stomach acid to properly absorb it and dietary fiber is known to weaken the stomach acid.(S,S2,S3) 

So the context matters - what else are you getting with the nutrients? For example, there are plenty of plant sources of iron, but plant foods like whole grains, legumes and nuts contain phytic acid that impairs iron absorption.(S) Spinach is thought to be a great source of iron but you can only absorb 2% of it because of the oxalate in it.(S) Then, where the heme-iron in animal foods is very easily absorbed, the non heme iron in plants and supplements is quite poorly absorbed. Two different literature reviews suggest that vegans are at greater risk for iron deficiency than omnivores. (S,S2)

Now before we continue, Why should we assume a meat containing diet was the natural default for humans rather than a plant-based diet?

Well,

To get a wide variety of nutrients, vegans have to eat a huge variety of modern fruits and vegetables, but the fruits and vegetables early humans had access to were nothing like modern ones. Before cultivation, they had far less actually edible material and far more fiber and seeds. Paleoanthropologist Daniel Lieberman has said that the sweetest fruit available would have been no sweeter than a modern day carrot. (S) Here’s a what some fruits and vegetables would have looked like before domestication.

Further our stomach acid is very suited for digesting meat at a strong pH of 1.5 - even stronger than carnivores like dogs or cats.(S)

We have stable isotope studies finding we ate pretty much whatever meat we could get our hands on… our earliest art is cave paintings of hunts.

Lastly, the brain is a disproportionately energy expensive organ, hogging 20% of our oxygen and calories.(S) Our guts (also energy expensive) shrank in size to allocate more resources to the brain.(S) Thus, to fuel our big brains, the more energy efficient animal fat became favored over fibrous plants that took time and energy to chew and digest. 

Most people are not aware that animal foods are packed with far more of a huge variety of nutrients, especially ones critical for brain function. This may have a role in why a 2021 study found people who don’t eat meat to have significantly higher risk of depression and anxiety. In fact, if you eat all the parts of a ruminant like a cow you can get every single essential nutrient - even vitamin C which is in the liver and adrenal glands. Oddly enough, recently some are eating only animal foods for years without any identifiable nutrient deficiencies - at least so far. I’m not saying 100% steak is the perfect diet and it’s probably not even natural - but it shows how nutrient dense animal foods are. There is no one plant food that you can rely on for years without quickly developing various severe deficiencies. 

By the way, I’m not saying don’t eat any plants - fruits and vegetables can be a great source of nutrients like vitamin C or manganese and important electrolytes like potassium and magnesium. Actually, the people of the high Andes identified kelp as a very mineral rich food. 

The peoples Weston price studied had an intuitive understanding of the importance of nutrient dense foods - especially in pregnancy and childhood. Even without a nutrition label, they knew that certain animal foods encouraged proper robust growth.  In fact, before pregnancy, they would commit to a period of “special feeding” usually at least 6 months where they would eat various animal foods dense in fat soluble vitamins and other nutrients - things like fish eggs, meat and high-fat dairy. 

As Michael Pollan has argued in his book In Defense of Food - we frequently fall victim to this concept of “nutritionism” that we don’t necessarily need whole foods, we just need their components. But certain supplements illustrate how it’s a lot more complex than that: 

According to a 2012 study, despite taking prenatal supplements, 58% of pregnant woman had iron levels below normal. 

Choline is a critical nutrient for brain function… and one study estimates 90% of Americans aren’t getting enough. A 2019 study found choline from egg yolks to be far better absorbed than choline from the common supplement choline bitartrate. Just 150 calories of egg yolk will give you over 100% your requirement.  

One study found that while dietary calcium reduced the risk of heart attack, calcium supplements increased the risk. Calcium can be hard for vegans to get enough of without supplementation. This 2020 study found vegans had weaker bones and a 43% higher risk for fractures than omnivores.(S)

I’m not saying supplements are all just bad, they indeed have been found to help people reach the appropriate intake of certain nutrients. I take some specific supplements myself. The point is there can be issues with relying on supplements.  

But before we fall victim to the appeal to nature fallacy, we can’t just assume something is healthy just because it’s natural. After all untreated water is very natural but it’s a great way to get dysentery. 

Here’s a different way to think about it:

Let’s start by rewinding back to 1932. Dr. Francis Pottenger had been trying to formulate a healthy diet for his laboratory cats - he assumed he had all the components necessary for a proper cat diet - raw milk, cod liver oil and cooked meat and organs. Yet for some reason his cats seemed to suffer from nutrient deficiencies. At some point he had so many cats that he had to cut corners - he started giving some cats their meat raw. Within a few months these raw meat fed cats and their kittens were clearly healthier than the cooked meat fed cats and kittens. 

This had Dr. Pottenger conduct a 10 year study to puzzle out the effects of cooked meat versus raw meat on hundreds of cats. He found that the cooked meat cats consistently had health problems but the problems were even worse for their kittens.  The kittens were born underweight, with brittle bones, their teeth were crooked and crowded, they had allergies, they had thyroids that didn’t function properly … then, all these problems were even worse for their kittens. In fact, the third generation of these cats didn’t survive more than 6 months - there was no fourth generation to study.  

The thing is initially, the deficient cat diet seemed … not too terrible. Sure the first cats had some problems, but the bigger problems started to appear in the kittens. Then the full picture of just how inappropriate this diet was appeared a generation later. 

By the way if the diet was at least 50% raw, then the cats developed well.

Now the point is not to say that we need to eat raw meat - we are not cats. 

The point is, it’s not about what’s natural, it’s about track record - it’s easy to observe the effect of a diet in cats quite quickly - in just 10 years Pottenger got a grasp of the track record for these two cat diets. With humans it takes far longer to see the generational impact of a diet. But, whatever we’ve been eating the past couple decades already has a pretty bad track record. 

Like the cats, some markers of our health seems to be worse with each generation. Something about our modern environment is leading to all kinds of problems:

-Dr. Sandra Kahn and Paul Ehrlich have written a book called Jaws: The Hidden Epidemic about the epidemic of small dental arches leading to crooked teeth & constricted airways, this leads to breathing problems like sleep apnea that take a huge toll on health..

-There’s been a tripling in peanut allergies

-Autism has increased 185 times from 1970 to 2020. (Rates went from 1:10,000 to 1:54)

-Prevalence of ADHD has steadily increased over the past 20 years.

-Incidence of depression in 12-25 year olds has more than doubled since 2008

But when it comes to diets, we know of one that has had a good track record. Maybe you’ve heard of the term diseases of civilization which refers to heart disease, cancer, osteoporosis, diabetes and so on - Anthropologists could tell you that before agriculture came along, Hunter Gatherers very rarely had any of these afflictions that are so common today. They also had robust skeletons and broad faces that allowed for straight , cavity-free teeth. If the dangers of living outdoors without the aid of modern medical care didn’t kill them, they lived quite long and without chronic disease(S2) 

As the name Hunter Gather would suggest, all parts of fish and animals were very valued parts of their diet. In the late 1800’s Plains Indians were the tallest people in the world and according to an anthropologist at Ohio State University, they had “a remarkable record of nutritional and health success.”(S) They ate tons of bison and preserved what they couldn’t fit in their stomachs as jerky or pemmican. They would even dry out bison guts and fill them with blood to drink when they were thirsty. 

While that sounds gross, they may have used it to hydrate cause blood would provide electrolytes   …

So, the past several decades has been one long push for reducing animal fats, and meat and organs in the diet. But plenty of recent research shows this isn’t a good solution for helath. A huge 2020 review explained that saturated fat rich foods like whole-fat dairy or unprocessed meat themselves are not associated with an increase risk of heart disease and a 2022 systematic review found the previous evidence that shows unprocessed meat is linked to chronic diseases like cancer or heart disease to be far too weak to make the recommendation to reduce meat consumption. Yet, the the anti-meat push has gotten so strong that as investigative journalist Nina Teicholz reveals, a recent Tufts University ranking system bogusly ranks Reese’s Peanut Butter Cups as healthier than Eggs, Cheese or Ground Beef.

It’s easy to assume that our understanding of individual nutrients is so advanced that we don’t need to rely on outdated meat-based diets - we can make replacements. 

But, while the amount of knowledge on nutrition that’s been accumulated is incredible, is it as complete as we assume?

In 1989 scientists decided that standardized lab rat chow needed to include several seemingly random things like chromium, fluoride, boron, vanadium, arsenic, nickel, lithium, tin and silicon. Why? Well, they didn’t really know what these things did … they just observed that the rats didn’t grow properly without them.(s)(s) Come 1993, they had to change the formula again to increase vitamins E and B12 and vitamin K needed to be increased 10 times. (S)

Even in 2021, this paper said the lab rat formula still needs to be updated as it doesn’t fully “reflect our understanding of animal nutrition.”

In 1978, a six-year-old girl was admitted to the hospital with a serious gunshot wound to the stomach. At the time just how essential omega-3 fatty acids are wasn’t fully understood. The liquified nutrition they gave her was deficient in omega-3’s, causing her to develop neurological symptoms like numbed legs and feet, drastic weakness and blurred eyesight. (S, Also see)

It wasn’t even until 1998 that the nutrient Choline was recognized to be essential. Liver disease, atherosclerosis and neurological dysfunction taught us that Choline is pretty important. 

A paper from just last year in 2022, suggests we underestimate the optimal intake of choline. This Cornell study found that seven-year-old children had better attention span if their mothers consumed twice the recommended amount of choline during their pregnancy.  

Formula

Finally, let’s go back to 1865 when the first infant formula was invented. It took many decades for quality and regulations to improve, but eventually infant formula came to be widely regarded as a safe substitute for breastmilk leading to a significant decline in breastfeeding.(s) Nestle notoriously suggested that their product was better than breast milk.  

Research has associated increasing trends of formula-fed children more easily developing eczema, asthma(S) and food allergies(S2,S3) as well as diabetes and obesity(S,S2).(S) A 2008 study found breastfed babies to have a 5 point higher IQ.(S) Today, the AAP, WHO, and UNICEF all recommend exclusive breastfeeding for at least the first six months of life.

If a mother can’t breastfeed or get donor milk, of course modern infant formula is basically a miracle. But even as a representative of Abbott, a leading infant formula manufacturer admits: “to mimic and replicate breast milk is not possible.” 

Formula manufacturers are constantly discovering new beneficial compounds in breast milk.(S,S2) - As recent as 2016 and 2019 two different new compounds started being added to formula because they improve infant gut and brain health. 

Dr. Rhonda Patrick has made an excellent video overviewing just how complex breast milk is. It contains:

・415 different proteins (s)

・200 different human milk oligosaccharides (s) 

・200 different fatty acids (s) 

・4 different types of growth factors 

And that’s not even the full list. 

Yes, a newborn will have far more sensitive nutrient requirements than an adult or even a child, but it’s an example the difficulty of trying to make a complete replacement of a natural food.

In fact, there are all kinds of compounds only found in meat that we currently assume are not necessary to have in the diet. Things like creatine, carnosine, anserine, taurine - there is evidence that each of these have beneficial effects.(S)

Just to look at two This 2002 paper argues that taurine may be essential in certain circumstances, and creatine supplementation has benefits for brain function in adults like improving memory, intelligence and mood and it reduces the negative effects of sleep deprivation.(S) Further, creatine is transferred from the mother to her baby during pregnancy providing several benefits to the baby.(S) 

The other thing is Reality versus Theories. The reality is that the average person doesn’t want to spend time worrying about nutrients. Again, meat is so nutrient dense that you can get a decent amount of well absorbed Zinc, Iron, Selenium, Choline, various B-vitamins, vitamin A, Calcium and other nutrients just eating a crappy cheeseburger. Ideally people shouldn’t eat crappy cheeseburgers… but the average busy person doesn’t have time to craft the perfect meal - convenience is important. This is evidenced by the fact that a 2021 paper found that the more people avoided animal products in their diet - the more they ate convenient ultra-processed foods with vegans eating the most processed foods.(S) 

Looking at the updated Impossible Burger Ingredient list, they basically swap the animal protein with soy and the animal fat with sunflower oil and coconut oil, and they throw in several other vitamins to mimic the vitamin profile of meat.(S)

Eating tons of processed soy protein and vegetable oils like sunflower oil is quite new to the human stomach. Sunflower oil seems like a simple swap for animal fat … but they are totally different. Many animal fats can be a good source of vitamin K2, but vegetable oil in fact hampers the activity of vitamin K, increasing your need for it.(S,S2,S3,S4) It also oxidizes very easily so it will increase your need for the antioxidant vitamin E.(S) Vegetable oil has several other negative effects which I have talked about in another video.

Vegans and vegetarians tend to rely on soy for protein a lot. The hormone disrupting effects of increased soy consumption is somewhat controversial, but it may explain why a study on almost 8000 boys found boys born to vegetarian mothers had a higher risk for a specific deformity in the genitals called hypospadias.(S) Soy contains the isoflavonoid genistein, which studies show has “detrimental effects on the male reproductive system…” (s)

Lastly, impossible burger has tried to make their product taste meatier with something called leghemoglobin from the roots of genetically modified soy plants. 

GMOscience.org writes that:

• A 28-day study commissioned by Impossible Foods in 2017 on soy leghemoglobin found that soy leghemoglobin caused statistically significant changes in weight gain, changes in the blood that can indicate the onset of inflammation or kidney disease, and possible signs of anaemia in the rats.

Further studies did eventually persuade the FDA to designate leghemoglobin as safe, but Impossible Foods admitted that a quarter their new ingredient was composed of 46 “unexpected” additional proteins, none of which were assessed for safety in the dossier.(S)

This reminds me of how we used to think margarine was a good heart healthy replacement for butter. Then around 1956 we learned the trans-fats in margarine are ironically awful for heart health and health in general. but it wasn’t until 2015 that the FDA acknowledged trans fats  are unsafe to eat and need to be removed from the food supply.(s,s).

This is another big issue with trying to replace animal foods. The replacement almost always comes with plenty of other stuff. Kidney beans are a good source of protein need to be soaked and cooked to reduce the lectin content. Some boys in the UK showed up in the hospital with profuse diarrhea and vomiting because they  ate 4 kidney beans that were soaked, but not cooked.(S) Certain people can still be sensitive to the trace amounts of lectins in properly processed kidney beans.Here is a list of other plant sources of lectins, but many commonly consumed plants have various other gut aggravating compounds like oxalate, FODMAPs, gluten or phytic acid.

Phytic acid found in beans, seeds, nuts and grains inhibits fat digetion(S) and the absorption of calcium, magnesium, phosphorus(S) and Zinc. How much? Well, this study found about 35% less Zinc is absorbed in a vegetarian diet. Fiber itself worsens the activity of pancreatic lipase which is important for the absorption of fat soluble vitamins like A, D and K2.(S) A high intake of goitrogenic foods like cabbage, kale and turnips can interfere with iodine functioning. 

Food Scientist Dr. Frederic Leroy has written an extensive article on the various examples of why it’s a challenge to acquire enough of certain nutrients just from plants due to inhibiting compounds like these. This nutrient challenge is part of the reason why The German Nutrition Society in 2016 and the French-speaking Pediatric HGN Group in 2019 recommend against a vegan diet for adolescents, children or mothers.

Several studies have found babies born to vegan mothers to have a lower birth weight than babies of omnivore mothers.(S,S2, S3, S4, S5  see also, see also, see also)

Birth weight can be a predictor of infant health and growth.(S,S2,S3, S4). In fact, one study that meticulously analyzed the records of 4,300 adults who were in the Danish Medical Birth Register  found that the lower their weight at birth, the shorter they would be as adults. 

This study points out that the growth of vegetarian children was adequate, but less than average. I wonder how people would react to a doctor saying “your son won’t be as tall as he could be, but don’t worry his height will be adequate.”

This begs another question: What is the difference between enough nutrients and the optimal amount of nutrients?

When you look at a nutrition label, it will tell you what % of your requirement for a nutrient you’re getting. This is called the RDA but it’s not set based on the optimal amount of that nutrient you should get. It’s set based on determining how much is enough to prevent a deficiency … and then recommending people get a bit more than that. (S)

For example, a previously mentioned study on choline found that a mother getting twice the recommended amount of choline has beneficial effects on children.

The RDA for vitamin D for adults is currently 600 IU’s, however the The Endocrine Society suspects that not even 1000 IU’s would be enough to provide all the “health benefits associated with vitamin D.” They recommend about 3 times the RDA - 1500 to 2000 IU for all adults.(S,S2)

In fact, vitamin K’s importance for bone health wasn’t properly recognized until 1997.(S) It wasn’t even until 2006 that the USDA thought it would be good to look at the vitamin K2 contents of common foods.(S) Yet today, there is still no RDA established for K2.

So, this isn’t only a criticism of a plant-based diet - obviously average person’s omnivore diet needs to drastically improve… and course nutrition isn’t the only reason people choose to be vegan……but cutting out nutrient dense animal foods doesn’t seem like a move in the right direction for health.

For 99% of human history we relied on animal foods for nutrients(S,S2) - the an animal food containing diet has a strong track record that spans arguably over 1.7 million years. Various cultures viewed animal foods as important to growth and despite the challenging circumstances they lived in, they were protected from infectious diseases, they didn’t have the modern diseases of civilization, and they enjoyed proper growth in their body, faces and mouths. With that in mind, a plant-based diet is an experiment without any meaningful track record. It’s been a couple decades at best that people have been doing vegan diets, yet already many people quit for health reasons. 

Research is a promising story of progress - maybe one day we’ll learn enough to make sufficient plant-based replacements for animal foods. But it’s probably not happening any time soon.