RDResponse

As an ethical vegan, I don’t think we need to eat animals for many reasons. As a registered dietitian, I know we don’t need to eat animals in order to have an optimal diet; however, I also can say that you don’t need to eat a vegan diet to have an optimal diet. If I can admit that from a strictly research-based standpoint, why can’t those advocating other eating styles embrace the idea? Why must they espouse so many falsities related to a vegetarian/vegan diet? It is simply untrue that you can’t be healthy on a vegan diet, which essentially was the basis of the article “Why You Should Think Twice About Vegetarian & Vegan Diets,” written by a well-known advocate of the Paleo diet.

(Go ahead, roll your eyes. I did. I won’t dwell on my feelings about the Paleo diet – I am all for people making better food choices, but I could give a damn what our ancestors ate back in the day from the standpoint of how it should impact our current eating patterns. It’s apples to oranges, y’all.  Side note: the anthropologist wannabe in me does find ancestral eating patterns super interesting!)

I would like to dissect the assertions in this article, starting with:

Vegan diets, in particular, are almost completely devoid of certain nutrients that are crucial for physiological function. Several studies have shown that both vegetarians and vegans are prone to deficiencies in B12, calcium, iron, zinc, the long-chain fatty acids EPA & DHA, and fat-soluble vitamins like A & D.

First off, being “prone to” a deficiency is not equal to actually having one. And most studies looking at vegan & vegetarian nutrition intakes also note that there are increased intakes of fiber, vitamins C & E, potassium, magnesium, folate, and phytochemicals versus omnivores. Ergo, with such eating patterns, there are decreased risks of cardiovascular disease, some forms of cancer, Type 2 diabetes, and obesity. And the essential premise that vegan & vegetarian diets are inadequate completely forgoes the official position paper by the Academy of Nutrition & Dietetics (the professional organization of registered dietitians) which states, “Appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases.”

B12 deficiency is especially common in vegetarians and vegans…The takeaway is that the most recent studies using more sensitive techniques for detecting B12 deficiency have found that 68% of vegetarians and 83% of vegans are B12 deficient, compared to just 5% of omnivores.

Let the cherry picking of studies begin! This particular study looked at subjects who were not supplementing with vitamin B12, so it is really no surprise that vegans would have low levels.  I don’t know any respectable vegan health professional who isn’t screaming from the rooftop about the importance of vitamin B12 supplementation, myself included. The author goes on to discuss a study looking at cognitive performance in former “vegan” kids and how it was lower than omni children. This study was done on macrobiotic children and mentions no indication as to whether the children were given vitamin B12 supplements at any point in time. Typically, macrobiotics discourages the use of supplementation. So again, not a fair comparison.  And if we are going to mention vitamin B12 deficiency, we must mention that it is recommended everyone over the age of 50 consume vitamin B12 supplements because our physiological ability to absorb it when bound to animal foods decreases as we age. Vitamin B12 deficiency doesn’t discriminate.

…trying to meet your daily calcium needs from plant foods alone (rather than dairy products or bone-in fish) might not be a great strategy.

Again, the same research review cited in the author’s case against vegan diets being low in calcium goes on to discuss the fact that vegetarians “typically have lower BMI, serum total & LDL cholesterol & blood pressure; decreased rates of death from ischemic heart disease, decreased rates of hypertension, stroke, Type 2 diabetes, & certain cancers than non-vegetarians.” Why aren’t these findings being discussed? Admittedly, vegans tend to consume calcium in amounts below the recommended level, but when we look at bone health specifically, there are so many influential factors beyond calcium. Sodium, vitamin D, & protein intakes also matter, along with engaging in weight-bearing exercise.

And let’s reflect on the fact that milk consumption as a “main source” of calcium is a newer habit in the course of human history. Wild greens had been providing our ancestors with calcium until we started suckling the teat of animals. The author goes on to state how much spinach one has to eat to equal the amount of calcium in a cup of dairy milk. This is an absurd comparison given that spinach is one of the high oxalate foods that does interfere with calcium absorption. On the other hand, kale, greens and bok choy are all examples of vegetables that provide highly bioavailable calcium to the body (and it’s more bioavailable than cow’s milk). And is it really a burden to have to consume more than a 1/2 cup serving of these veggies as the author alludes? Calcium-fortified non-dairy beverages, calcium-set tofu, and other calcium-rich sources (like blackstrap molasses & beans) are possibilities to meet your daily requirement – and therefore you aren’t left to have to eat cups & cups of greens should you not choose. I know folks in the Paleo crowd tend to frown upon fortified foods (& supplements), but more on that in a bit.

Vegetarians eat a similar amount of iron to omnivores, but as with calcium, the bioavailability of the iron in plant foods is much lower than in animal foods…

It is true that animal sourced iron (heme) is more easily absorbed by the body, but that does not mean someone eating solely plants cannot obtain enough iron to meet his/her needs. And yes, there are compounds in plants which affect the bioavailability of iron; however, there are also ways to enhance iron absorption (like adding vitamin C rich foods to the meal). Iron deficiency affects omnivores as well – it is the most common worldwide nutrient deficiency. It was such an issue in our population that iron began to be added to flour in the 1940s, and today, grains are the main source of iron in the diets of American adults. And lower iron levels do not equate to an iron deficiency. In fact the same study that the author cites in his post also states, “Although it is clear that vegetarians have lower iron stores, adverse health effects from lower iron and zinc absorption have not been demonstrated with varied vegetarian diets in developed countries, and moderately lower iron stores have even been hypothesized to reduce the risk of chronic diseases.” Um, yeah…so there is that. And there is also the issue of adaptation, in which the body learns to reduce iron losses and increase absorption of the mineral in response to a diet high in nonheme iron.

Before I end this, I would like to briefly touch upon the issue of supplements. Many within the Paleo community essentially believe supplements shouldn’t be needed if you are eating properly (Paleo). As you have seen from the author thus far, it would appear he isn’t fond of supplementation (and perhaps fortification) based on his views that vegan diets are “devoid of certain nutrients” including vitamin B12. Obviously vitamin B12 is easily obtained via fortified foods & supplementation. It is a non-issue.

The author addresses the issue of supplements on his webpage stating, “However, I have also stated from the beginning that certain nutrients are difficult to obtain even in the context of a healthy diet (such as vitamin D and magnesium), and supplementing with them indefinitely may be necessary. I call this ‘maintenance supplementation’. Other nutrients that may fall into this category, depending on your diet and health needs, include vitamin A, vitamin K2, selenium, iodine and vitamin C.”

Now I am really confused. So, if you are eating Paleo, you may still run the risk of having multiple nutrient deficiencies? Additionally, you may need some other supplements to get you through the Paleo transition phase – and luckily, the author has his own line of supplements for sale. I am sorry – you cannot have it both ways. Chastise one method of eating for potentially lacking in nutrients and having to resort to supplementation while saying your method is The. Way. to eat – but oh yeah, you will probably need to  supplement at the same time. It just makes you look silly. If you don’t like veganism, that is your right. Just be damn honest about it because your dietary advice clearly isn’t coming from a place of science.

Photo credit: KD Traegner