Vitamin B12 is probably the most debated topic in the plant-based community. It is vital for our health but there is still incomplete research regarding the optimal source, dosage, and frequency of obtaining B12. Even Dr. McDougall admits it is tough to give advice on Vitamin B12 so you are definitely not alone! Follow this link to see what top vegan doctors are saying about B12 in a short panel discussion https://www.youtube.com/watch?v=wwjoYq6fTdA.
Vitamin B12 is one of the most important molecules for our body. This holds true for everyone but especially vegans. Doctor Michael Klaper has a comprehensive explanation on the topic of B12 (https://doctorklaper.com/answers/answers27) and on NutritionFacts.org, Dr. Gregor also has a series of educational videos on this topic. We highly recommend you make use of these great resources. Alternatively, keep reading this article as we will summarise the current research and guidelines on B12 for you!
Function and importance
Vitamin B12, also known as cobalamin, plays a vital role in the synthesis of DNA and, essential for the health of your blood, bone marrow, and nervous system (which includes the brain, spinal cord, and peripheral nerves). Deficiency of vitamin B12 can lead to fatigue, anemia, dementia, paralysis, and other detrimental health complications.
Source of B12
It is commonly mistaken that B12 is only available through consumption of animal products and is produced by animals. However, B12 is exclusively made by microorganisms living in soil and water. It is found in the muscles of animals and therefore consumed in meat. In earlier times, humans acquired vitamin B12 in the same way as grazing animals – ingesting bacterial B12 from the surface of root vegetables and stream water. Nowadays, traditional sources of B12 have been virtually obliterated by our modern lifestyle in the process of sanitation. As a consequence of the absence of traditional sources of B12, modern day vegans must rely on vitamin B12 supplements to meet their B12 needs. It is important to understand that this requirement is an artifact of modern sanitation and NOT proof that humans need to eat animal flesh.
Know your B12 level
When your blood is tested, you want to test for: (1) Vitamin B12, (2) Homocysteine, and (3) Serum Folate. Although the lower limit of “normal” Vitamin B12 value is set at 200 ng./L, people may suffer from fatigue, anemia, sore tongues, and nerve damage at that low level. Dr. Klaper advises his patients to keep their B12 level well over 600 ng/L.
If there is not enough active vitamin B12 in your tissues – or not enough folate from eating dark green vegetables, homocysteine can build up in your bloodstream and leads to damage of artery walls. As a result, if you have a blood test, always ask for all three measurements!
Supplement: type, dose, frequency
This is where it gets tricky as you will find different doctors recommending different things. The reason is that some research still needs to be done and to date, there is no definitive answer as to which supplement regime is the best. However, we do know that the recommended dietary allowance on public guidelines is inadequate because our body absorbs only a small portion of the B12 we take in(Bor et al., 2010).
Dr. Gregor recommends that for adults under age 65, take at least one 2,500 mcg cyanocobalamin each week or a daily dose of 250 mcg. He also notes that cyanocobalamin is the preferred supplemental form of vitamin B12, as there is insufficient evidence to support the efficacy of the other forms. For those over 65 who eat plant-based diets, the supplementation should probably be increased up to 1,000 mcg of cyanocobalamin each day. Pregnant women should also increase their dosage.
Dr. Klaper, however, prefers the methylcobalamin form of vitamin B12 and recommends 1000 mcg – 2,500 mcg., twice weekly. He also favours B12 supplements in the form of liquid drops or sublingual “microdots” that melt under your tongue because they allow contact of the B12 with a protein in saliva that promote better absorption into your bloodstream.
It is okay to be confused about different information, we have to accept the fact that research is a time-consuming process and a definitive answer is not always available. Our recommendation to you is to be safe than sorry, take one 500/1000mcg B12 tablet every day as this is the most common and cheapest option on the market. Double the dosage if you are pregnant or over 65. Take a blood test after 3 months and bring the results to a trusted doctor or us so that we can help you make educated decisions on whether your body is absorbing enough B12 and adjustments are needed.
It is possible but challenging to get sufficient amounts of B12 from B12-fortified foods. Research has shown that under-the-tongue cyanocobalamin and nutritional yeast, but not probiotic supplements are effective in preventing B12 deficiency (Donaldson, 2000). In addition, some seaweeds consumed in large amounts can supply adequate amounts of bioavailable vitamin B12. However, the average use of seaweeds and fermented foods do not supply enough vitamin B12 (Rauma et al., 1995). In summary, to get sufficient B12 from food sources only is challenging. It is cheaper and more convenient to just take a supplement.
Is your body absorbing B12?
To see if your body is actually absorbing the supplemental B12, Dr. Klaper suggests that “It is wise to have your B12, folate, and homocysteine levels measured 90 days after beginning a supplement program to see if you need to take more or less”. It is also a good practice to do a complete blood check every year to verify that your nutritional needs are met.
We hope that this article is useful in explaining why you need B12 and how to get enough of it to stay healthy on a plant-powered journey. It is not difficult and we will always be here for further support if you need it. Just like other doctors, we frankly do not know the best recipe for obtaining B12 yet due to incomplete research. Therefore, advices may change in the future as new research results come out. So in the meantime, take supplements and stay tuned!
Information for readers
This article is written by our science communicator from Vegan Palette (Bachelor of Biomedical Science, University of Queensland). Linkedin profile: https://www.linkedin.com/in/yunan-ye-science/. While author aimed to be unbiased during production of this article, readers are encouraged to validate the content by reading the original articles provided. Note that not all research articles are open-access. If you encounter difficulty accessing a particular study or have questions during your own research endeavours, please contact Vegan Palette for assistance or seek professional advices from our accredited practising dietitian. The article remains intellectual property of the author.
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About the author
Raymond Setiadi is an Australian Accredited Practising Dietitian and is the founder of Vegan Palette, a Brisbane-based dietitian practice.
As an expert in whole food plant-based nutrition and fat loss strategies, Raymond has a comprehensive understanding of the interplay between food, human physiology, goal-directed psychology, and how they all play a pivotal role in one’s pursuit of optimal health.