Vitamin B12. My Vegan Experience

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Vitamin B complex plays an important role in the process of nutrient conversion from the food we eat into energy. Most of the vitamins of this group are found in sufficient quantities in various plants. The only exception is vitamin B12. This vitamin is not synthesized by plants; it is produced by bacteria and microorganisms. In this article we will discuss this unic vitamin. 

12 years without supplements (my personal experience)

Throughout my vegetarian period of life (since 2008) I didn’t care about vitamin supplements. During all this time (12 years) I could take only multivitamins, rarely and inconsistently. And I had only one 10 day-course of vitamin B12 injections during this time. While I was transitioning to veganism I began to dive deeper into understanding nutritional needs for healthy living. Still I could not convince myself to take vitamin supplementation seriously.

Although vitamins are not medicine, for some reason I had a strong resistance to taking pills (or whatever comes from a pharmacy).  Until I was finally ready to take better care of myself, admit my pain and consider information, where B12 supplementation was discussed as a canker sores treatment.

Canker sores and B12

I suffered with canker sores (stomatitis) since my teens… it was a terrible pain, and each time I had to find new ways to cope. The canker sores in my mouth seemed to adapt to the medicine I used: what helped ones, the other time no longer had any effect. I tried Kamistad Gel, Metrogyl Denta, Urgo Filmogel and other ointments. Also, I tried to rinse my mouth with sesame oil, with soda and salt dissolved in water, I tried to chew cloves, drink mint tea… I even tried to cauterize it with brilliant green and vodka!

Over time, things only got worse. First stomatitis appeared every time I bit my lip or tongue, then later it could appear from nothing, even if I was extremely careful. In the end, it got to the point when canker sores appeared regularly, every month, despite any precautions. I noticed clear correlation – it appeared right before menstruations. Menstruations were painful on their own, with vivid PMS symptoms, skin problems and hair loss. So this period was a period of my suffering indeed.

Last summer, I finally decided to visit all necessary doctors with the firm intention to find the cause that unites these problems and to help myself with it. Honestly speaking it was difficult to take this step, since problem wasn’t so bad, compared to diabetes, insomnia, irregular menstruations, broken leg or what so ever … It was shameful to complain, but now I’m so happy that I managed to overcome this distructive feeling. First, I went to the dentist to ask about canker sores. The dentist said that it is an autoimmune issue – there can be a lot of reasons, and there is practically nothing to help. So I went to check vitamins and hormones …

Vegans and vegetarians in Cyprus can take the B12 test for free!

Luckily, the GeSY was introduced in Cyprus by this time (General Healthcare System) and it became easier and cheaper to get tested. Surprisingly vegans and vegetarians registered in GeSY (General Healthcare System) have privilege in terms of Vitamin B12 test.

So my blood was examined for thyroid hormones, iron, hemoglobin, vitamins. All indicators were normal, except for B12. Although 266 pg/ml is still considered to be normal in Cyprus, in Germany that would be considered as a deficiency. Luckily, I have a vegan friend in Germany, who told me about this, otherwise I could ignore it – since it is still a norm – why bother?

I decided to set a goal and raise the B12 level to 400 pg/ml, hoping that this might be a solution to at least some of the problems. My husband and I shoveled all over the Internet to understand this vitamin. We found that the liquid form of the vitamin is best absorbed. Also we found that this vitamin is better to drink on an empty stomach and that it is desirable that it has time to mix with saliva, since saliva contains proteins, binding with which the vitamin will be protected from acid when it passes through the stomach. In addition, we learned that even with normal B12 levels, its intake helps people to heal canker sores! In general, we learned a lot of interesting details, and I decided that this should definitely be shared.

Forms of Vitamin B12

Vitamin B12 is a group of bioactive cobalt-containing substances. This group includes methylcobalamin, cyanocobalamin, adenosylcobalamin, hydroxocobalamin, but there are also other forms. Vitamin supplements typically use either methylcobalamin or cyanocobalamin. Methylcobalamin is an active form of the vitamin that our body can immediately use for its intended purpose. Cyanocobalamin is a synthetic, more stable form of B12. It is more resistant to light and to the environment (vitamin B12 is destroyed by light, and by an alkaline environment), therefore, it is more common to use cyanocobalamin to enrich milks, sweets, muesli, and so on. However cyanocobalamin is not the active form of the vitamin; the body converts it to methylcobalamin and / or adenosylcobalamin first. During this process, a small amount of cyanide is released, so theoretically, this form of B12 in large quantities can be toxic.

The effect of taking the vitamin (my case)

In order to urgently raise my B12 level, I decided to have a 10-day course of methylcobalamin injections, and then switch to B12 supplements in the form of drops (on a daily basis). My husband and I were looking for drops that contain both forms of the vitamin B12 – methylcobalamin and adenosylcobalamin. I drank 4 drops on an empty stomach every day. The result is impressing. In 7 months my B12 level reached 710 pg/ml and finally situation with canker sores got better!


Injections of vitamin B12 may cause acne

However, effect was not instantaneous. When I started supplementing vitamin B12 in the summer, I noticed that after a month the canker sores stopped appearing and the condition of my skin turned better. I was cautiously happy and optimistic. I started my 10-days course of injections and I thought this will do me even better, but I had an adverse effect! Canker sores began to appear again and rashes on the face seemed to be even worse than before. Can’t convey my disappointment. My last hope to get rid of these problems was dying. But! just released a video, describing this phenomenon. Turns out that big amounts of B12 (more than 5000 mcg a week) may cause acne. This can only happen if you treat vitamin B12 deficiency with injections. So that’s what had happened!

And in the same video doctor Greder reminded, that any change takes time. This encouraged me to continue taking the vitamin regularly, and as a result, over the past 4 months, I had not a single canker sore in my mouth.  Condition of my skin has improved. Significantly fewer acne appears during luteal phase. My hair also got stronger. I used to collect tangles of my lost hair from the floor every week, now this is not the case. I didn’t even think it was possible.

Why you may consider supplementing Vitamin B12?

We require B12 for the adequate functioning of blood cells and the nervous system. Lack of this vitamin can lead to serious consequences (such as anemia, bone marrow diseases) and less serious, but very nasty problems (migraine, canker sores, depression, painful periods, skin and hair problems).

Vitamin B12 is involved in the process of red blood cells production, a lack of this vitamin in the blood can lead to B12 deficiency anemia (Addison-Birmer disease / Pernicious anemia). Anemia is a condition, in which the content of functionally complete red cells (erythrocytes) is reduced in the blood. Unlike iron deficiency anemia (which is characterized by production of red blood cells with a low hemoglobin content), Addison’s disease means that megaloblasts are produced in the bone marrow (abnormally large cells with an undeveloped nucleus and a high content of cytoplasm) . Megaloblasts cannot turn into red blood cells and die in the bone marrow. This leads to concomitant problems in all body systems.

Original sources of B12 Vitamin

The primary sources of the vitamin are bacteria and archaea (microorganisms) that live in water and (therefore) in the soil. Bacteria synthesize B12, which is then absorbed by phytoplankton, then eaten by zooplankton, which is then eaten by fish and animals that drink water and eat grass. Thus, B12 enters the body of animals, absorbed in the small intestine and accumulates in the liver and other tissues of animal bodies. So, people state that the main source of B12 are the liver and kidneys of large fish such as tuna, cow’s liver, kidneys and meat. Vitamin B12 is also found in mushrooms, spinach, asparagus (which is expectable, since these plants grow very close to the ground).

Animals drink unfiltered water and eat unwashed plants, so they get enough vitamin B12 from their food. We cannot rely on B12 directly from primary sources, because we filter the water and wash the vegetables. Therefore, it is highly advisable to monitor your B12 levels and take vitamin supplements. And I will note – it is desirable to do so not only for vegans, but also for any person. I even have a suspicion that a B12 deficiency may threaten vegans to a lesser extent! Vegans are still under the scrutiny of society, and are more likely to go and check their level of vitamin B12 than an average person relying on the effectiveness of a “proven” lifestyle.

Does our body produce B12?

Just like in the case of animals, vitamin B12 can be produced by bacteria in our intestines. The only problem is that these bacteria live in the large intestine, and the absorption of the vitamin occurs in the small intestine (first, food enters the small intestine, then the large intestine). Ruminants have an advantage. Unlike us, they have an additional section in the stomach (rumen) where B12-producing bacteria live. Those animals that are deprived of a rumen do not hesitate to eat their excrement, which contains the very same vitamin B12 produced by bacteria in the large intestine, but not absorbed.

It’s good that we are sophisticated species and vitamin B12 is available to us in the form of a supplement!

What is daily requirement of vitamin B12?

You may be confused by the fact that the daily intake of the vitamin is only 2.4-7 mcg (that is, as much as found in 100 g of dried shiitake mushrooms), but tablets are sold in huge dosages of 1000 mcg. That is because our body can absorb only 1% of the incoming vitamin at a time. 1% is passively absorbed and only 1.5 mcg can be captured by receptors in the small intestine every 1-2 hours.

Therefore, two logical approaches are to drink the vitamin twice a day in small doses of 250 mcg, or drink 500 mcg of the vitamin once a day. Preferably on an empty stomach. There were no cases of overdose or negative effects from the regular use of high doses of the vitamin taken orally (injections may cause acne in dosade over 5000 mcg a week).

Pay close attention to this indicator, and if possible, do blood testing. An indicator of 190 – 950 pg/mL is considered to be normal, but in Germany, at a level below 400 pg/mL, a course of treatment is prescribed. There are also recommendations to drink higher dosages of the vitamin for pregnant women and elderly people. It doesn’t matter if you are vegan or not! In this video, Dr. Greger explains why.

Sources of B12 in Plant-Based Foods

Nowadays, many products are enriched with cyanocobalamin. This form of B12 is resistant to conditions (as I mentioned before), so foods such as vitamin B12-fortified plant-based milk, cereal, nutritional yeast, tofu, tempeh (and other) I would consider the most reliable and understandable nutritional source of vitamin B12.

However, there is one disadvantage. Often brends enrich their products with B12 AND B9 at the same time. B9 is also known as a folic acid. The synthetic form of this vitamin is very toxic, and there is more than enough of natural vitamin B9 in raw vegetables. So I prefer to avoid this vitamin as a supplement.

Wikipedia also mentions that a small amount of B12 is found in mushrooms, especially in dried shiitake (5.6 μg per 100 g). But it all depends on where and how these mushrooms grow. Some mention nori and other algae as a B12 sorce- however, the quantities are likely to be negligible.

Why animal-derived foods are not a good source of vitamin B12?

As a nutritionist, I believe that animal products cannot be a reliable source of vitamin B12. Despite the fact that the main source of B12 in the dominant diet is considered to be animal products, even in the meat of cows it is contained in relatively small quantities (0.7-1.5 μg per 100 g, depending on the body part) and when cooked a significant part of vitamin B12 collapses (source). Another example – eggs. Less than 9% of the vitamin is absorbed from eggs, i.e. only 0.08 μg (source).

Even when it comes to cow liver, which is considered as one of the richest sources of B12 we have a problem. People rarely eat this product daily, especially in its raw form. For clarity: according to various sources, 100 g of raw beef liver contains 60-80 μg of vitamin, but 100 g of cooked liver contains only 24 μg (source). That is, 40-60% of the vitamin is destroyed during cooking. If the liver was boiled in water some of B12 will be dissolved in the water along with toxins (since the vitamin is soluble in water). And I will remind you once again – our body can passively assimilate only 1% of the consumed vitamin (this will already be 0.24 μg from 100 g) and only 1.5 μg can be grasped by the receptors (from 100 g of liver it comes out less than the daily norm).

I see it complicated

And still we are not taking into account many indirect factors. There is no guarantee that slaughtered animals themselves are not deficient in B12. No guarantee that cobalamin in its tissues will not collapse from exposure to light while being on the counter in the store. And bioavailability of vitamin B12 will be different depending on the type of animal. I am not even talking about all unwanted components, that come hand in hand together with animal-derived B12, such as colesterol, estrogens, carcinogens etc.

Here I am providing a short list of products which are considered to be vitamin B12 sources in public. I decided to make it complicated: I searched for the most plausible information, because sometimes they give us confusing data. For example: they say in boiled clams the content of B12 is as much as 98 μg per 100 g, while in raw clams there is only 11 μg per 100 g. Where these numbers come from, I could not understand.

The data in the table below is mainly taken from the USDA database ( U.S. department of agriculture). The database is huge and respected, but it is not always clear how exactly the product was studied. For example, that clams. Whether they were weighed together with the shells, or without? Whether the same clams were cooked or from another batch?  And often the indicated data is very old. Over 30 years the habitat has changed a lot. I managed to find more recent and (in my opinion) unambiguous studies for some products. Those I marked with a single star. Links to sources of information should be active.

B12 content in plant-based foods and animal-derived products

(after cooking)
Nutritional Yeast, enriched

25-150 mcg**~25-150 mcg**
Cereals, enriched 0.6-6 mcg**~0.6-6 mcg**
Dried shiitake up to 5.6 mcg*no studies yet
Soy milk, enriched 0,4-3 mcg**~0,4-3 mcg**
Tempeh, enriched0.18 - 4.8 mcg**~0.18 - 4.8 mcg**
Cow liver 60-80 mcg* 23.83 mcg* (fried)
clam11.28 mcg12.77 mcg

Tuna 2.08 mcg1.61 mcg (slow cooked)
Cheese (Gouda) 1.54 mcg
Beef 0,7-1,5 mcg*0,2-0,5 mcg (~ -32% )* (fried)
Cow's milk 0.54 mcg
Chicken0.38 mcg0.34 mcg (fried)
Egg0,89 mcg 0.08 mcg*

*Non-USDA source

**The B12 content of fortified foods is always different depending on the brand and country. So in the table I have indicated the average values.

My choice

Vitamin B12 (Vegan)

B12 in the form of dietary supplements is now my conscious choice. In general, I tend to use whole foods in my diet and rarely buy processed foods, which are usually fortified with vitamins. We also make plant-based milk at home by ourselves (more for environmental reasons). So it feels safe and reasonable to take supplements. Once you get used to it, drinking vitamins in the morning becomes commonplace.

We drink this B12 every morning on an empty stomach, 2-3 drops. Taking into account the blood test results and how I feel, it works effectively. Also good thing that there are both methylcobalamin and adenosylcobalamin of high bioavailability in these drops. And it's vegan 🙂


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Anastassiya Vizzini

I am Anastassiya - Vegan Nutritionist, author and administrator of the Vizzini Journal. I have been vegan since 2017 and I feel the urge to contribute into development of this movement. It is my sincere belief that maintaining vegan lifestyle is something truly self-loving. And I think that self-love is the strongest tool you can use to change the world around you for the better.

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