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Vegans and Vitamin B12

The human body is made up of many complex compounds. We know them by the terms of vitamins, minerals, proteins, carbohydrates etc. Each of these compounds has their individual roles in helping our body function as it should and help us remain healthy. One such crucial compound that our body needs is Vitamin B12.

Vitamin B12 is the nutrient many medical doctors claim to be most difficult for vegetarians to obtain. It is produced only by microorganisms and thus found more often in animal-based products.

Vitamin B12 is required for red blood cell formation and normal growth, it is important for fertility and during pregnancy, builds immunity and treats some degenerative diseases, and it is used therapeutically in many mental and nervous disorders. More recently it has been used to energize the body and counteract allergens.

Despite Vitamin B12 being a core building compound in the human body, there has been an increase in Vitamin B12 deficiency in the past decade. Fall insufficient intake of B12 food has been pointed to be the reason for this. Unlike most compounds, the human body does not produce any B12 naturally. This makes intake of sufficient B12 in our food imperative.

So, what is B12? Why is it so important?


  1. Understanding Vitamin B12
  2. The benefits of Vitamin B12
  3. How much B12 is needed?
  4. Signs of Vitamin B12 Deficiency
  5. Effects of vitamin B12 deficiency
  6. Veganism and B12
  7. Vegan Sources of Vitamin B12
  8. Supplements for B12

understanding vitamin b12

Understanding Vitamin B12

Vitamin B12 is the largest and most complicated vitamin that our body needs. It is also known as cobalamin, which is soluble. Like all the other B vitamins, B12 is a water-soluble compound. It dissolves when in our body and travels through our bloodstream.

B12 plays the important role in producing red blood cells and DNA in our body. Without sufficient B12, the human body will not be able to produce the required amount of red blood cells. Other than this, B12 is also important for the proper functioning of the nervous system. Deficiency in B12 could lead to disorder related to the nervous system.

But as mentioned, B12 is not naturally produced and stored in the human body. It has to be consumed via food. It is important to consume the suggested vitamin B12 dosage every day. A deficiency in B12 leads to a whole range of health issues. Not only can this, diagnosing the B12 deficiency be complicated. Early diagnosis almost never happens. During diagnosis, a vitamin B12 deficiency could be mistaken for a folate deficiency. Folate is one of the B-vitamins that is needed to red and white blood cells in the bone marrow. Folate also helps convert carbohydrates into energy and produces DNA. Because folate is an important part of vitamin B12, fall in B12 leads to decrease in the folate level. However, adjusting the folate level via medications will only mask the deficiency completely ignoring the real problem.

The benefits of Vitamin B12

Adequate intake of B12 is important in all stages of life. It is especially important for pregnant women, infants and the elderly. It helps in growth and is needed for nerve tissue health and brain function. Not only does the vitamin help in producing red blood cells, but it also helps in regulating DNA and RNA.

It is the Vitamin B12 that helps the body to produce the energy it needs to function. B12 does this by regulating the metabolic process in the human cells that synthesize fatty acids and absorb folic acid to produce energy. Therefore, B12 is the center of one the most important processes our body does to keep us healthy and alive.

How much B12 is needed?

The National Institutes of Health (NIH) recommends that everyone above the age of 14 should consume 2.4 micrograms of vitamin B-12 per day. This is the average recommendation. Here are the different recommendations:

0 – 6 months 0.4 micrograms (mcg)
7 – 12 months 0.5 mcg
1 – 3 years 0/9 mcg
9 – 13 years 1.8 mcg
14 – 18 years 2.4 mcg
Adults 2.4 mcg
Pregnant women 2.6 mcg
Women who are breastfeeding 2.8 mcg

As it can be seen in the table above, depending on the age of the person, the recommended intake of B-12 varies. B-12 is key for the healthy development of an infant. This is why women who are pregnant and breastfeeding are required to consumer more B-12 than everyone else.

elders and vitamin b12 deficiency

Signs of Vitamin B12 Deficiency

Vitamin B-12 is absorbed from the food we eat. As a person grows older, it might be difficult to absorb and retain this vitamin. Absorption is also a problem for those who have had weight loss surgeries or any surgery that has removed a part of their stomach. Similarly, it can also be difficult for those who consume a lot of alcohol to absorb vitamin B12. It is when the body is not able to successfully absorb and retain b12 from the food we consume, we get diagnosed with a B12 deficiency.

Some people are more at risk of having a vitamin B12 deficiency. This is because their body lacks some compounds that absorb B12 and retains in for our body to use. And this eventually leads to levels of vitamin B12 being too low. In the United States, nearly 15% of the population was diagnosed with a vitamin B12 deficiency in the year 2017.

People who are more prone to be deficient of vitamin B12 are:

  • Vegans
  • Elderly people, especially those who have had surgeries where parts of their stomach were removed
  • People with diabetes. More specifically if they are on the drug metformin
  • People taking long-term antacid drugs for heartburn
  • People who have
    • atrophic gastritis
    • Pernicious anemia
    • Crohn’s disease and/or Celiac disease
    • Immune system disorders or Lupus

 With this steady increase in vitamin B12 deficiency, it is important for people to check for b12 deficiency often. Negligence in checking and maintaining B12 could have dire consequences.

Symptoms of vitamin B12 deficiency

Symptoms of vitamin B12 deficiency

  • Pale and yellow skin: People who have a b12 deficiency tend to look paler and have a yellow tone on their skin. It is not only the skin, the whites of the eyes also have a yellow tinge to them. This is because the body is unable to produce enough red blood cells. Without sufficient b12, the cells are unable to divide to create new red blood cells. This could lead to megaloblastic anemia in which the cells produced in the bone marrow are weak. When our body does not have enough red blood cells or the cells produced are weak, our skin will look pale.
  • Weakness and fatigue: The second symptom to look out for is fatigue. When the body does not produce sufficient red blood cells, it becomes difficult for the blood to transport oxygen through the body.
  • Pins and needles: Another symptom that indicates a deficiency in b12 is a constant or regular sensation of pins and needles. This sensation indicates some kind of nerve damage. The effect of this may not be immediate. Over time, lack of b12 can lead to reduced production of the fatty substance in our body called myelin. This substance plays an important role in protecting our nerves. Without b12, we lose the compound that protects our nerves from damage and enables proper functioning of the nervous system.
  • Issues with mobility: Insufficient b12 will have an effect on our balance and coordination while walking. This is a symptom that is seen more among the elderly. Medicines can be taken to improve and help issues with mobility. Young people with severe deficiency could also show this symptom.
  • Glossitis and mouth ulcers: B12 deficiency can lead to change in color and shape of the tongue. The bumps in our tongue that functions as taste buds stretch and disappear. It could be painful to speak and eat.
  • Breathlessness and dizziness: This comes from having anemia. When enough red blood cells, there is not enough oxygen in the body. This can lead to dizziness and breathlessness.
  • Disturbed Vision: Another symptom of 12 deficiency is an issue with vision. When b12 deficiency attacks our nervous system, it could lead to vision impairment. This is known as optic neuropathy. This condition is reversible by taking b12 supplements.
  • Mood changes: A theory suggests that low levels of b12 that lead to increased homocysteine could be the reason for constant mood changes during the deficiency. This can also be reversed by taking b12 supplements.

It should be remembered that all the symptoms given above could be the result of some other health issue and not b12 alone. It is best to consult with a doctor before arriving at any conclusions.

The earliest signs of B12 deficiency are weakness, listlessness, fatigue, diarrhea, depression, and indigestion. Other signs are paleness, numbness in the fingers and toes, heart palpitations, anorexia, shortness of breath, infertility, and mental imbalances including faltering memory, moodiness, apathy, paranoia, hallucinations, violent behavior, personality changes, and other derangements.

The tongue is an indicator of serious B12 deficiency. It becomes red, shiny and smooth, and is sometimes ulcerated. In the final stage before death, irreversible paralysis and brain damage occur.

Symptoms of vitamin B12 deficiency do not always show—they can be masked by the B-complex vitamin folic acid. Folic acid and B12 have certain similar functions, and each requires the presence of the other in many of their activities.

Anyone, vegetarian or omnivore, with weak digestion, can become deficient in vitamin B12. In addition to poor digestive absorption, there are other specific factors that deplete the body of vitamin B12:

  • Birth control pills and antibiotics
  • Intoxicants (alcohol, cigarettes, coffee, and all others)
  • Stress from any source, especially from injury, surgery, or trauma
  • Liver diseases and chronic illnesses.

Effects of vitamin B12 deficiency

Effects of vitamin B12 deficiency

Deficiency of vitamin b12 has a huge impact on our body. Because b12 is the nucleus of the effective functioning of the brain and the nervous system, a deficiency could cause permanent health issues and/or disorders.

The first thing that b12 deficiency causes are fatigue. An individual who does not have sufficient b12 will not have enough energy to get through the day. They will be constantly tired. Other than this, people can also have depression, confusion and memory problems. These are triggered when there is a slight fall in b12. However, it should be noted that b12 deficiency may not be the only issue causing these issues. Other health issues that people with the b12 deficiency will have is constipation, loss of appetite and weight loss. If the deficiency is not kept in check, it could escalate to neurological issues and disorders. It could lead to serious brain and nerve damage. People who do not have sufficient b12 are at increased risk of developing psychoses, dementia, and mania.

Infants will have impaired growth and may also have face tremors, reflex problems, feeding difficulties, and irritation if vitamin b12 is not checked and kept in control. Similarly, insufficient b12 in adults could lead to anemia. Individuals with anemia will experience sore tongue and mouth, weight loss, pale skin, diarrhea, and menstrual problems.

Above all, vitamin b12 deficiency makes people more susceptible to the effects of all allergies and infections. Fortunately, there are some signs and symptoms that we can keep an eye out for that could indicate a possible deficiency in vitamin b12.

Veganism and B12

The best sources of b12 lie in animal-based foods such as meat (pork, beef, poultry, fish etc.), dairy products, eggs, and nutritional yeast. Because of this, individuals who follow veganism tend to be more prone to be deficient of vitamin b12. However, this can easily be adjusted by taking b12 supplements and b12 fortified food. Many products today such as soy milk, cereals and yogurt are fortified with b12. This will help vegans meet their required b12 needs. To meet b12 needs while adapting veganism it is suggested that –

  • Eat fortified foods twice or thrice a day
  • Take a weekly supplement of b12

It is recommended that individuals who are relying on fortified foods for vitamin b12, check the labels and packaging to ensure they are getting sufficient b12.

Pregnant women and mothers who are breastfeeding should consult with doctors if they are adopting a vegan diet during pregnancy and breastfeeding. This is because b12 is crucial for an infant to develop healthily.

Vegan Sources of Vitamin B12

Vegan Sources of Vitamin B12

Fermented Foods

These include miso, soy sauce, tempeh, pickles, amasake, nut and seed yogurts, and sourdough (naturally leavened) bread.


Tempeh, a currently popular cultured soy product with origins in Indonesia, has some of the highest B12 content of any food (up to 15 micrograms of the vitamin in a 100-gram serving).


Scientific tests have shown a number of algae to be excellent sources of B12. In fact, microalgae such as spirulina and chlorella are considered some of the highest food sources of vitamin B12.

Certain macroalgae—nori, wakame, and kombu seaweeds—are sometimes touted as having significant B12 content.

Nutritional Yeast

Nutritional yeast has been used as a B12 source for vegetarians for more than thirty years. A problem with yeast is its very nature: microorganisms of this sort tend to induce unhealthy amounts of candida-type yeasts in the body, especially in individuals who are susceptible to Candida overgrowth. Find out more about it, here.

Protein and Vitamin B12 Sources

The B12 requirement is one to three micrograms per day for adults, if taken from natural sources, and it can triple if taken from supplements. Here is a table with the best vitamin B12 and protein sources for vegans and their concentration.

Vegan foods with vitamin b12 – Table was taken from the book Healing with Whole Foods: Asian Traditions and Modern Nutrition by Paul Pitchford

Vegans and Vitamin B12 | Protein and Vitamin B12 Sources for Vegans and Vegetarians

vitamin b12 supplements

Supplements for B12

When people do not get enough b12, supplements are suggested to ensure their body gets sufficient b12 for healthy functioning. For those who are consuming Vitamin B-12 via supplements, it should be noted that Vitamin B-12 reacts with different medications differently. The most commonly known medications that react negatively with the vitamin are metformin, proton pump inhibitors, h2 receptor agonists that are used for peptic ulcer disease. Another medicine that can react negatively with B-12 and interfere with red blood cell production is the antibiotic chloramphenicol.

B12 supplements can be taken orally or in a nasal spray. For those with a high level of deficiency, b12 can be injected directly into the body. B12 supplements are available for purchase in all health food stores. There is almost nil or negligible side effects to taking b12 supplements. It is still highly advised that individuals consult with their doctors before taking b12 supplements.

Bottom line

B12 is significant for the human body to function properly. Although, it is mostly available in animal-based products, there are many alternatives that can be adopted. Those with B12 deficiency can take B12 or multivitamin supplements. People who do not eat animal-based foods can switch their diet to include B12 fortified grains, supplements, injections or oral vitamins.


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Wednesday 6th of September 2017

The EASIEST and BEST thing you can do is to get 'Metabolics B complex' in liquid and take it daily in a glass of for example orange juice.


Thursday 7th of September 2017

Thanks for the tips!


Friday 2nd of October 2015

The sources for b12 that are mentioned are either b12 analogues (means they can't be absorbed and used by the body) or not reliable sources of b12 (like tempeh or regular nutritional yeast)


Tuesday 19th of May 2015

I'm glad I found your article. I've recently transitioned into a vegan diet and b12 is the only thing I have yet to master so I'm thinking about supplementation and proper fortified foods.


Thursday 28th of May 2015

Glad it helped! :D

Nutritional Supplement

Friday 28th of June 2013

I think that vegans and vitamin b12 are interrelated with each other. I think that vegans should always consider the importance of vitamin b12 in their diet. I know that there would be new ways on how vegans can obtain such vitamins.