Vegan Equals Deficient?

Vegan diets and lifestyle have been increasingly gaining popularity in the Western world. Many believe that it has not been put to the test of time or think that relying solely on plant sources of nutrients is not compatible with human health. However, for millennia, large groups of people worldwide have thrived on plant-based diets. The longest living people today, to name a few, the Okinawans, the Ikarians and the Seventh-day Adventists, turn out to be the ones that eat mainly vegan or vegetarian. Additionally, nearly a century-long, cumulative body of scientific research confirms and explains the reason why whole-food plant-based diets are strongly associated with good health outcomes.

Some of the largest studies done on the effect of different diets, have clearly demonstrated that vegan diets decrease all-cause mortality; significantly lower the chances of developing diabetes type 2, hypertension, atherosclerosis and heart disease, and even cancer. Furthermore, whole-food plant-based diets are associated with a greater health span and lower incidence of age-related cognitive decline and other comorbidities. An even more exciting implication of plant-based diets is their therapeutic potential in different states of disease. Complete clinical reversal of heart disease has only been documented using a whole-food plant-based diet, where the dietary intervention group showed clearing of atherosclerotic plaque and, in essence, no cardiovascular event throughout the study, while the control group followed the typical bleak course of the disease (Esselstyn CB Jr. et al, 2014).

Lately, however, new diets have emerged that completely contradict all current research and make bold claims. Few among them have become popular as the Paleo, the Ketogenic and the Carnivore diet. They are, essentially, based on consuming animal products with varying ratios of fat to protein and partly or completely excluding plants. It is worth mentioning, that no one of the three diets has enough scientific data to back them up nor have they been tested over centuries by indigenous people and proven healthy and promoting longevity. Moreover, a well-known group of indigenous people, the Inuits, that eat large amounts of fish and aquatic or semi-aquatic mammals have a relatively short life expectancy. Heart disease and atherosclerosis prevalence among these arctic inhabitants is equal to or greater than that seen in the US, which does not even necessitate further investigation of their dietary habits as they are, obviously, futile.

While there is compelling data to support all aspects of a vegan diet and conclude that plant based eating is ‘appropriate for all stages of the life cycle’ (Academy of Nutrition and Dietetics (AND)), opponents have come up with strong criticism and, largely, unscientific claims against veganism. Among other things, some of the claims can be quite worrisome and confusing for the vegan individual. Often they argue that plants cannot provide sufficient amount of protein, lack essential nutrients, are high in carbohydrates, can rob the body of essential minerals. Others can go further and say that plants are toxic, and their toxins are natural pesticides like lectins, oxalates and phytates. Once again, no one of those claims is substantiated by real science. In fact, some of those ‘toxins’ could be adding to the therapeutic power of plants as lectins are proteins that the humans’ immune system also produces and they can directly kill or inhibit pathogenic bacteria and viruses, along with cancerous cells. Phytates, in turn, can inhibit cancer growth and chelate heavy metals that accumulate in the body leading to all kinds of disease.

In realistic settings, only a few of those ‘plant toxins’ can cause discomfort and threaten someone’s health. Peanut lectins are very immunogenic, which means, they can overstimulate the immune system and cause various inflammatory states, mainly allergic reactions. Gluten found in grains can exacerbate leaky gut and cause intolerance or the inflammatory state of the gut known as Celiac disease. On the other hand, gluten has not been proven to cause any issues in healthy individuals. However, there is a big catch; traditionally gluten-containing foods have never been eaten the way they are consumed today. The traditional ways of preparing food, very often, include deep cooking and/or fermenting. Grains, in particular, have always been deep-fermented, be it in bread or in beer, which can dramatically lower their gluten content and increase their nutrient availability.

Food preparation and nutrient availability are interconnected and are of great importance for a healthy vegan diet. Pressure-cooking, soaking and fermentation are all crucial for a vegan-eater. These methods allow the plants to release some of their anti-nutrients, be less harsh on the gastrointestinal tract, and improve nutrient absorption greatly.

There are certain nutrients that long-term vegans may be deficient in – zinc, omega-3 fatty acids, and vitamin B12. Other nutrients that vegans are claimed to be deficient in – choline, vitamin K2, vitamin A and protein. The latter four are only made-up claims, plants can meet the choline requirement of a person, and some common choline-rich plants are; green peas, brussel sprouts, and tomatoes. Regarding vitamin K2, it turns out that all westerners are, to some extent, deficient, and it might be good to supplement MK-7 particularly, but not obligatory. Vegans might even have higher levels of K2 as it can be synthesized from vitamin K1, which is abundant in plants, while being scarce in animal products. When it comes to vitamin A, it is rather ridiculous to claim that vegans cannot get enough, as a regular plant-based diet provides up to 15 times the requirement in the form of carotenoids. The classic evergreen argument that vegans are protein-deficient could not be further from the truth. In addition, high-protein intake is linked to many diseases as kidney disease and cancer. Furthermore, legumes, grains and pseudo-grains like quinoa can meet and even exceed the daily protein requirement.

On the other hand, vegans can become deficient in vitamin B12, omega-3s and zinc over time. Most of the plants contain plenty of copper, which can easily exceed the daily allowance. In the intestines, copper and zinc have an antagonistic relationship, if the diet contains more copper, it will inhibit the absorption of zinc and vice versa. As plants provide little zinc and a lot of copper, vegans can become zinc-deficient over time, which may cause depressive symptoms, anxiety, slow wound healing, hair-loss, brittle nails and bones among others. Adding a low-dose of 10 to 15mg daily zinc supplement can help avoid any risks related to deficiency or simply consume nuts like pumpkin or sunflower seeds.

The body cannot synthesize vitamin B12 nor can terrestrial plants, the only producers of the vitamin are certain soil bacteria. B12 is essential for cellular division, DNA repair and the nervous system. While the body has its own reserves that can last for years, supplementing either daily or weekly will keep things safe.

Omega-3 fatty acids can be obtained from flaxseed or quinoa in the form of alpha-linolenic acid, which is beneficial per se, but can also be converted to EPA and DHA by the liver. The conversion rate is usually very low, but in vegans, it rises, as the body does not receive exogenous omega-3s, thus helping avoid deficiency. However, as they are critical for optimal health, no risk should be taken and supplementing algae-based omega-3s on a weekly or daily basis is warranted.

In a nutshell, vegan diets can come in great variation though, for instance, white bread and refined sugar are technically vegan foods, yet detrimental to health. A better name for the diet described in this article would only be a ‘whole-food plant-based’ diet, where anything processed is avoided. While there is, and will be massive criticism against veganism, it is unquestionable that it is suitable for all stages of life, promotes longevity and better athletic performance, healthy ageing and last but not least, sustainability.

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