Potentially Missing Vitamins in the Vegan and Vegetarian Diet
The decision to become vegan or vegetarian is easier said than done. Agreeing to make the switch from eating to abstaining from meat or dairy requires many sacrifices. Being vegan or vegetarian limits the variety of foods available and involves researching extensively on whether certain foods are vegetarian or not. While the reasons for making the switch vary (to detoxify, lose weight, save animals, etc.), new vegans and vegetarians often neglect to fully consider everything their bodies need. To stay healthy, the human body needs a spectrum of vitamins to carry out the essential chemical processes for life. However, to a layperson, what each vitamin does in the body can be a mystery.
One of the main concerns that arise when switching from an all-inclusive diet to a meat-free one is the increased chance for vitamin deficiency. As serious health complications can arise from long-term deficiency in any of the main essential vitamin, it is therefore absolutely necessary to have a clear sense of what each vitamin does and how it can be obtained as the all-inclusive diet changes to a strict primarily plant-based one.
Vitamins are nutrients that cannot be synthesized in living organisms in sufficient amounts and hence need to be obtained through diet. Thirteen vitamins are considered to be essential for carrying out normal cellular functions for life. These vitamins go into the formation and maintenance of the entire body. They are classified by their biological and chemical activity as opposed to structure. Each category named, for example, like “Vitamin B,” actually consists of subsets and alternate forms depending on how they are absorbed by the body. The thirteen categories are A, B1, B2, B3, B5, B6, B7, B9, B12, C, D, E, and K. Vitamins are either fat-soluble or water-soluble, depending on how the body absorbs them. Vitamins A, D, E, and K are fat-soluble since that they go down the digestive tract to be absorbed in the small intestine. The other nine vitamins are water-soluble, where they are absorbed into the lymph system and subsequently to the blood.
Though many vitamins are found in both plants and animals, a few, like Vitamins A and D, are meat-exclusive. Many vegans and vegetarians take daily supplements to compensate for these meat-only vitamins. However, many are not fully informed as to what these vitamins specifically do for the body.
Animal products such as meat, egg yolks, dairy, and fish are all good sources of vitamin A. Non-vegans can easily obtain this nutrient by consuming meat products, where vitamin A is already in a form easily utilized by the body. The vitamin A that is found in the orange and green vegetables that vegans normally eat is beta-carotene, which is one member of a group of red, orange, and yellow pigments called carotenoids. The body must convert beta-carotene into Vitamin A, which is used to maintain eyesight, cell development and growth, and immune system functions. Vitamin A functions by binding to rhodopsin, a pigment in the retinas, to help sense UV light (Miyazono, et al. 2011). Besides that, the vitamin also helps to decrease the risk of contracting diseases and dying from severe infections (Nutri-Facts.org 2015). In pregnant women, the vitamin decreases the risk of maternal mortality by enhancing the immune system to fend off infection (Faisel, et al. 2000).
These plant-based carotenoids, however, can only supply 50% of the total Vitamin A needed in the diet. Deficiency of vitamin A can cause night blindness and corneal lesions (WHO 2002). However, because the vitamin can be stored in the liver, excess amounts of it taken over a long period of time can damage the liver, lead to increased risk of osteoporosis, and contribute to lung cancer (Beta-Carotene;Web-MD). In many parts of the developing world, vitamin A deficiency affects one third of all children worldwide who are under five years of age. It is also suggested that vitamin A deficiency may even be linked to causing about 16% of the total malaria cases: this lack of vitamin A is associated with the retinal whitening, discoloration, and hemorrhagic (bleeding) symptoms seen in severe malaria cases (Sithole 2011). For vegans and vegetarians, vitamin A deficiency can be solved through consumption of carotenoids in plants like carrots and broccoli.
Biotin (B7), folate/folic acid (B9), niacin (B3), pantothenic acid (B5), riboflavin (B2), thiamin (B1), B6, and B12 are the eight subsets of vitamin B. Biotin, pantothenic acid, folate, riboflavin, thiamin, and niacin are found in non-meat and milk-free products. These are all water-soluble, meaning that they must be constantly replenished because they are excreted with urine. Biotin and pantothenic acid help break down food while riboflavin, niacin, and thiamin help the body utilize fat, protein, and carbohydrates to produce energy (NatureMade.com 2015). Folate is used to create DNA (Group 2015). Because of their plentiful plant sources, these subsets are often not deficient in vegans.
Instead, vegans and vegetarians are more likely to suffer from B6 and B12 deficiencies. B6 creates antibodies to fight disease; maintains normal nerve function; regulates blood sugar levels; breaks down proteins in the diet; and makes hemoglobin, which carries oxygen in the red blood cells. Deficiency results in symptoms like seizures and anemia (New York Times Health-Guide). There are three forms of B6: pyridoxine, pyridoxamine, and pyridoxal (Masterjohn 2009). Plants, like avocado and bananas, supply pyridoxine, while meat and dairy provide pyridoxal and pyridoxamine. However, the pyridoxine in plants is fairly useless in the body: it must be converted into these other two forms found in meat by using vitamin B2, or riboflavin. Coupled with the fact that most plants have a majority of their B6 bound so tightly with sugars that it is hard to absorb any of it, deficiency of B6 can be a very big problem for vegans. However, it can be resolved by eating avocados, bananas, legumes, and whole grains.
Deficiency in vitamin B12 is perhaps one of the biggest problems for vegans. B12 creates blood cells and repairs myelin, which helps maintain the nervous system. However, B12 is found only in meat and animal products (Chandra 2015). The liver can store B12 for three to five years if B12 consumption stops, such as is the case when people first become vegan. Without enough B12, however, over a long period of time, the body can experience multiple symptoms like anemia, loss of balance, weakness, and numbness in the arms and legs (Medline Plus) Chronic B12 deficiency is irreversible, as it can lead to degeneration of the spinal cord. Luckily for vegans and vegetarians, there are B12 supplements and B12-fortified foods that can remedy these symptoms. As B12 is water-soluble, any excess vitamin will simply be excreted through the urine (Masterjohn 2009).
Lastly, another essential nutrient that vegans and vegetarians often lack is vitamin D. Like vitamin B12, vitamin D is also found only in animal products such as cod liver oil, shrimp, dairy products, and egg yolks. However, it can also be created in the skin when exposed to direct sunlight (i.e. not through a window!). For those who live in the Northern Hemisphere where sun is often low in the sky during the winter months, getting vitamin D by sunlight is not feasible (Harvard T.H. Chan). Among its many uses, vitamin D primarily functions to increase calcium and phosphate absorption and promote bone formation. Deficiency can lead to a slew of conditions, such as high blood pressure, diabetes, and constipation (NatureMade.com 2015). For many vegans, their vitamin D comes from the sun, vitamin D- fortified foods, supplements, and mushrooms (Medline Plus 2016).
The switch to a vegan or vegetarian diet is a very serious one, as the lack of any of the essential vitamins can cause severe diseases and health complications. It is important to talk to a doctor or consult a dietician to ensure that there is a smooth transition from an all-inclusive diet to a vegan or vegetarian one. Certain vitamins, like B12 and vitamin D, are only naturally found in meat and dairy products. The nature of vitamins is also worth noting, as water-soluble vitamins such as vitamin B12 need constant replenishment. Others, like Vitamin D, which can be stored for a long time, do still warrant monitoring. In the first few weeks after making the switch, vegans and vegetarians often keep lists of the foods they have consumed. As with any dietary change, small adjustments such as mood swings can develop. Overall, going vegan or vegetarian is an important lifestyle choice that, if made with a determined heart, has the potential to lead to a happy and healthy lifestyle.