So you’re considering giving up animal products in favor of a plant based diet, but you keep running into self-proclaimed experts who want to scare you that vegans are at a higher risk for nutritional deficiencies. You know, like Vitamin A, B12, iron, D3, EPA, DHA, K2, and invariably, protein. But what does the science say? Do vegans have any reason to be concerned? Okay, let’s take these one at a time.
Vitamin A is a fat-soluble vitamin that is found preformed in animal products or is synthesized in your body from provitamin A carotenoids, like beta carotene.
While it is true that Vitamin A from animal sources are used more readily by the body, as shown in this 2010 study by Tang, absorption rate is virtually a non-issue for vegans because provitamin A carotenoids are found in such great abundance in a balanced plant-based diet. Vegans typically reach their bodies’ Vitamin A demands within one or two meals.
A 2006 study by Penniston and Tanumihardjo found that toxicity levels of preformed Vitamin A can be reached at just twice the daily recommended intake, whereas your liver will regulate the production of Vitamin A when you consume provitamin A carotenoids and toxicity is “largely impossible.” In other words, it is easy to overdose on vitamin A from animal products but impossible to do so from plant sources.
It is worth noting that there exists an inverse correlation between BMI and the beta carotene conversion factor. In other words, the more body fat an individual has, the lower their capability to convert beta carotene into vitamin A. A vegan of normal BMI will synthesize vitamin A without any issues.
While it is wise for vegans to eat fortified foods or to consume B12 supplements, meat eaters are also consuming B12 supplements indirectly because livestock feed is supplemented with B12 to keep animals healthy. This is not exclusively a vegan deficiency, nor is it exclusively a human deficiency. It does, however, speak to a soil crisis with much larger implications for modern industrial farming.
Eating animals does not naturally meet your body’s B12 needs – this only occurs when farmers introduce it artificially into livestock feed. So why don’t we, the humans, just take the supplements directly and avoid the cholesterol and saturated fats that are found in meat?
Now that’s food for thought.
Iron is found in two forms – heme iron which comes from animal sources and non-heme iron which we get from plant sources.
Iron is an essential nutrient but too much can lead to death. A 2010 study by Sharp supported earlier findings that unfortunately, the body has no mechanism of ridding itself of excess iron so choosing your dietary sources is extremely important.
For this exact reason, iron absorption is regulated by the intestines as shown in this 2005 study by Steele, Frazer, and Anderson.
West and Oates found in their hallmark 2008 study that heme iron has the ability to bypass the body’s regulatory mechanism, thereby disposing the body to toxic overload.
In a 2012 study by Ward and associates, the researchers demonstrated that heme iron, the type found only in animal products, causes DNA damage and leads to oxidative stress which directly feeds cancer cells. It has been shown repeatedly to promote esophageal cancer by catalyzing endogenous formation of N-nitroso compounds, which are the potent carcinogens also found in cigarettes.
A meta-analysis of 59 epidemiological studies from 1995-2012 by Fonseca-Nunes et al. corroborated this finding 2 years later that heme iron is a significant risk factor for various forms of cancer because it is a prooxidant.
Bao and colleagues reported in their 2012 meta-analysis that heme iron is also a significant risk factor for type 2 diabetes.
According to Yang and associates as published in 2014, there is no safe level of heme iron intake. As little as 1mg/day, or only 5% of the daily requirement of iron, was shown to increase risk for coronary heart disease by 27%.
They concluded, “This meta-analysis suggests that heme iron intake was associated with an increased risk of CHD.”
So, if iron from animal products has no safe limit, the question next logical is: do people who follow plant-based diets get a sufficient amount of non-heme iron? Saunders, et al. concluded in 2013 that they “are not at any greater risk of iron deficiency.”
Vitamin D3 is a fat-soluble hormone produced in the skin when it receives UVB sunlight.
Generally speaking, 90% is produced by the body and 10% is consumed by diet, so if an individual is deficient in vitamin D, it makes much more sense to address this by spending more time outdoors than through one’s diet.
As of 2011, 41.6% of Americans were found to be deficient in vitamin D although only 2.5% of Americans were vegan that same year, thereby reaffirming that this is not a dietary problem, it is a lifestyle problem.
According to the National Institutes of Health, as little as 5-30 minutes of midday sun exposure per week is enough to prevent symptoms of deficiency. Additionally, there are plenty of bioavailable plant sources for vitamin D such as sun-exposed mushrooms or lichen.
When you combine this with the fact that dairy products are fortified with vitamin D, just like we discussed with B12, it makes more sense to supplement directly than to consume animal products that are artificially fortified.
It is worth noting that the darker your skin and the higher BMI you have, the more sunlight you need to produce adequate levels of D3.
EPA & DHA
EPA, or eicosapentaenoic acid, and DHA, or docosahexaenoic acid, are both omega-3 fatty acids that are important for the brain, heart, joints, and eyes, among other things, although a 2009 study by Sanders found that “there is no evidence of adverse effects on health or cognitive function with lower DHA intake in vegetarians.”
While there are both plant-based and animal-based dietary sources of preformed EPA and DHA, our body has a mechanism to convert alpha linolenic acid, a shorter omega-3 found in plant oils, into EPA and DHA.
Because microalgae are one of the most prolific sources of dietary EPA and DHA, it is widely believed that fish are the best source of these nutrients for humans, therefore vegans are deficient.
A 2008 paper by Welch, et al. found that the conversion of ALA into EPA and DHA was actually 22% greater in vegetarians than in fish-eaters, demonstrating how the body will create more of these omega-3 fatty acids if need be.
Still, meat proponents will claim that because the ALA conversion to DHA is only 3.8%, this is somehow not enough for vegans to meet their needs, which is simply untrue. As little as one tablespoon of flax oil or 3oz of walnuts, for instance, would be enough to meet the daily recommended intake, without taking into account the rest of the food consumed that day.
A 2012 study by Oken, et al. reminds us that while fish contain essential fatty acids, they are rich sources of methylmercury and other toxicants and are inferior sources of EPA and DHA compared to plants.
Not only that, but Bao et al. found in 2013 that consumption of nuts were associated with decreased risk of cancer, heart disease, respiratory disease, and all-cause mortality.
Rizos and colleagues published a meta-analysis in 2012 demonstrating that fish oil supplementation was not associated with a lower risk of all-cause mortality and heart disease.
Vitamin K2 is a fat soluble vitamin that is produced endogenously in the body and can also be acquired through diet. It plays a role in bone strength and heart health.
Certain vegan foods are actually the best sources of K2, such as sauerkraut or natto. Natto actually has the highest concentration of K2 of any food we know of. That being said, vitamin K2 is produced by healthy bacteria inside the GI, therefore deficiencies in adults are very rare.
K2 can also be synthesized in arterial walls, the pancreas, and testes. It stays in the bloodstream for long periods of time, which is yet another reason that vegans are unlikely to develop deficiencies.
To put it simply, just like vitamin A, EPA, DHA, collagen, and biotin, your body will produce the vitamin K2 it needs.
It is worth noting that while vitamin K2 improves arterial function, animal products that are high in K2 – such as eggs, milk, cheese, beef, and chicken – are also high in saturated fats which inhibit endothelial cell function (1, 2, 3) and cause coronary heart disease. So eating these animal products negates any benefit of the K2 one would hope to gain from them. This could explain the conflicting research on the benefits of dietary K2.
Although paleo and meat proponents really emphasize the need to supplement K2, only one study, published in the Netherlands in 2004, has been put forward showing that K2 supplementation could possibly reduce the risk of heart disease and the findings were admittedly weak.
However, a German study by Nimptsch, et al. found the exact opposite – that K2 supplementation actually posed a greater risk for heart disease.
First of all, let’s refute the misconception that animal proteins are better for you than plant proteins. In 2016, Song et al. conducted the largest study ever performed comparing animal and plant sources of protein in the human diet consisting of 131,342 participants running for 26 years found a positive association between animal proteins and cardiovascular death as well as all-cause mortality and lower risk of death with plant proteins.
Okay, next, let’s dispel the myth that vegans cannot get enough protein in their normal diet.
The Academy of Nutrition and Dietetics’ official stance is, “Vegan diets typically meet or exceed recommended protein intakes, when caloric intakes are adequate.”
Let’s first remember that all proteins are originally synthesized by plants. All whole plant foods contain protein and all animals get their protein directly from plants or indirectly by eating other animals.
In 2015, Babault, et al. found that pea protein actually promoted a greater increase in muscle gains as compared to whey protein.
A 2007 study led by Kalman completely refuted the misconception that soy protein adversely affects the sex hormones testosterone and estrogen and instead suggested that whey protein could potentially adversely affect these androgens because it contains hormones from the cow.
Allen and associates found in 2002 that plant proteins are better than animal proteins at regulating serum IGF-1 levels which are a risk factor for cancer.
Combine this with the fact that plant foods have a complete amino acid profile, as demonstrated by McDougall in 2002, and there is no reason to ever consume animal proteins.
Official Position of Academy of Nutrition and Dietetics on Plant-Based Diets
Well-designed vegetarian diets provide adequate nutrient intakes for all stages of the lifecycle and can also be useful in the therapeutic management of some chronic diseases. Overall nutrition, as assessed by the Alternative Healthy Eating Index, is typically better on vegetarian and vegan diets compared with omnivorous diets.
Compared to nonvegetarian diets, vegetarian diets can provide protection against many chronic diseases, such as heart disease, hypertension, type 2 diabetes, obesity, and some cancers. Furthermore, a vegetarian diet could make more conservative use of natural resources and cause less environmental degradation.
In 1984, the Oxford study looked at 11,140 participants and found that vegans have a lower risk of heart disease, cancer, diabetes, and all-cause mortality even after adjusting for smoking, BMI, and social class.
Perhaps a question we might want to ask is why is none of the research cited in this video is being promulgated through mainstream outlets? Why is there still the prevailing narrative that we need animal products to stay healthy?
So, let’s recap. Wherever there are nutrients found in animal products, there are better versions of those same nutrients found in vegan products.
And contrary to what the myth mongers would have you believe, there are no nutritional deficiencies that exclusively affect vegans.
Sticking to a balanced plant-based diet is not only feasible; it is vastly superior in regard to health, sustainability, and cost. Tofu and other meat alternatives often cost 10 cents on the dollar compared to real meat. Therefore, you are spending more money and going out of your way to poison yourself.
Consuming animal products needlessly causes the suffering and death of animals. Now that you have seen the science, the impetus is on you to change. Whatever your reason for consuming animal products, be it tradition, taste, or an irrational fear of inadequate nourishment, you no longer have any excuse. You’re not tough because you eat meat, and it’s not cool to be flippant about causing suffering and death.
For those that attempt to justify eating meat because it makes you feel “grounded,” a shocking amount of cognitive dissonance is required for you to feel balanced and connected to the Earth while you consume the slaughtered carcasses of gentle, innocent, and defenseless beings.
The same degree of cognitive dissonance is required when meat eaters feign offense when they are encouraged to live compassionately. Instead they retaliate with a tu quoque fallacy, condemning the vegan for taking the moral high ground and then attempt to criticize the vegan for minor imperfections. Meat eaters who dig their heals in and resist the logic and deny the science of veganism are themselves committed more to convenience than truth and they should be called out for it.
Perhaps the greatest improvement any one person can make to their diet and health would be to cut out all animal products immediately. Perhaps the greatest impact most of us can have on the environment, the economy, and on world hunger is by going vegan. And perhaps the greatest shift we can make as a species is one towards compassion.