Do I Need A B12 Supplement?

Do I need a B12 Supplement?

Common scenario…

Client… “I take a B12 supplement every day”

Me… “Why?”

Client… “Because I’ve just cut out animal products, so want to make sure I don’t get a deficiency.”

Me… Ok, this is not a 1-min quick answer, grab a cuppa, put your feet up and listen…

Firstly, it’s important to know the role of Vitamin B12  in the body, what foods it is found in, how the body stores it, how much we need for optimal health and factors that increase or reduce its absorption…

The Role It Plays…

B12 is a vital component of the Myelin Sheath which surrounds some nerve cells. It is essential for the proper functioning of the nervous system, normal blood function, metabolism of protein, energy production, plays a role in DNA synthesis and the production of neurotransmitters. A lack of B12 can result in brain fog, memory loss, lethargy, light-headedness, shortness of breath, flatulence, constipation and/or diarrhea, muscle weakness, numbness, tingling and mental issues such as depression. (Note: These are also symptoms of other conditions so don’t race off and get B12, keep reading first).


b12 vegan healthy
Where it can be found…

B12 is synthesized from bacteria found in the soil and naturally occurs in microorganisms that live in our intestines. It is found almost exclusively in Animal products (more about this later). You can find trace amounts in some plant-based sources such as certain algae and plants exposed to bacterial action but they are not always easily absorbable. You can also find it in fortified plant-based foods.

Where it’s stored in the body…

B12 is stored in the liver for 3–5 years, other storage sites are the kidneys and the adrenal glands. So, it is highly unusual for a healthy individual, with no medical conditions, to become deficient in just a year, or even two, on a vegetarian or vegan diet.

How Much You Need…

For optimal health, depending on your age, gender or whether you have a medical condition… you’ll require anywhere from 0.4mcg to 2.8 mcg a day. However, only a maximum of 1.5 mcg is absorbed in a meal. A little more (a minuscule amount) is absorbed in the large intestines through passive diffusion. So taking too much just gets excreted.

What decreases its absorption…

A Vitamin B12 deficiency is more about malabsorption, than not getting enough. Ironically, those that pop a pill, eat animal products or spray B12 under the tongue, can still be deficient in this vitamin. And that goes for all other supplements you may be taking. If you don’t address the ‘why’ is there a deficiency you are essentially ‘band-aiding’ the problem and perhaps making it worse. That’s because vitamins and minerals work synergistically and antagonistically with each other e.g. taking too much of one vitamin/mineral can cause a deficiency in antoher.

Here are some possible reasons for Vitamin B12 deficiency…

  • Poor stomach acid. There are a number of reasons why low stomach acid occurs, however, one very common reason is the fact that many of us do NOT take the time to sit and eat slowly. This is a vital action in the role of stomach acid production. We eat on the run, work while eating, scroll social media and gulp our food down.
  • Gastrointesintal Mucosal Hyperpermeability is when there is damage to the cells’ tight junctions makes the lining of the Gastrointestinal tract permeable. This can be brought on by small intestinal bacterial overgrowth, low stomach acid, yeast overgrowth, previous infections, antibiotic and medication use, parasites and stress. This can damage the parietal cells where Instrinsic Factor, a transport protein, helps to transport B12 into the blood.
  • Medications taken for indigestion and acid reflux reduce stomach acid and can reduce the release of gastric acids which reduce the absorption of B12 E.g Proton Pump Inhibitors (PPI) and Gastric Acid Inhibitors such as Mylanta and QuickEze
  • Inflammatory Bowel Diseases (IBD) such as Ulcerative Colitis and Crohnsoften have impaired release and production of  Intrinsic Factor.
  • Increasing age 10 to 30% of people 60yrs + malabsorb B12. This is largely due to low stomach acid production.
  • Excess Alcohol consumption decreases absorption. Yeh I know, a bugger hey!
  • The oral contraceptive pill decreases absorption.
  • Large doses of Vitamin C may decrease absorption.
  • High heat when cooking may decrease absorption of B12 as it is sensitive to heat.
  • Pernicious anemia a medical condition where there is damage and a loss of the parietal cells in the stomach.
  • Autoimmune Conditions whereby the body’s immune system mistakenly attacks the parietal cells that produce Instrinsic Factor.
  • Worms and parasites can damage the intestinal wall and reduce Intrinsic factor.
How to increase B12 absorption…

Work on taking care of your gastrointestinal (gut) health. Stop eating crap – sorry if that sounds harsh 😐 but it is true. Eat whole plant-based foods. Cut out the sugars, salts, preservatives, emulsifiers, additives etc. These kill off your good gut bacteria — the ones that fix your stomach lining (parietal cells) on a daily basis keeping them in tip top condition so you can absorb  B12 ,and other vitamins and minerals for that matter!

And very important… Take the time to eat SLOWLY  so the process of digestion can function correctly. Probably not the scientific answer you were looking for right? But you have to get your digestion right as it is a huge part of the issue of ‘absorption’ of  B12 and ALL vitamins and minerals.

So should you take a B12 supplement just in case…

NO. NO and NO. A blood test and investigations need to be done  before taking any vitamin supplements. The ‘More is Better’ or ‘Just in Case’ attitude to popping supplements can be detrimental to long-term health and can cause more harm than good. The body is complex and, as individuals, we all have different requirements. Get tested before self-medicating.

If you are TOTALLY plant-based then you should be tested regularly (and not just B12, iron too). You may need to take a supplement if really really low however for most people the ‘food method’ is always preferable due to the other synergistic vitamins and minerals that are present in the food.  I like Spirulina powder, pop in your smoothies (1.8mcg per 1/2 tsp) or choose fortified in B12. And if blood test results are REALLY low, I always recommend a sublingual spray over a tablet, and not a cheap over the counter one!

And please… don’t forget about all the other factors I mentioned.

Now having said ALL of that… one more thing I point out to my clients. A lack of Vitamin B12, or a deficiency, is not exclusively the realm of a plant-based eater. In recent years due to large-scale animal production more animals are being fed grains rather than grazing on grass and studies show that animal products are now low in B12.  Even chickens often don’t have the opportunity to peck in the dirt as they used to result in some eggs shown to have NO B12 component.

And even when animals do eat grass unfortunately heavy antibiotic use in the farming industry kills B12 producing bacteria in the guts of these animals. Many meat eaters have marginal vitamin B12 status.

There’s so much more to talk about with B12 but I think you may have finished that cuppa and have things to do 😉

So if you have any questions, comment below.

Yours in Health, Natalie xx

Medical Disclaimer: Information provided in this article is for information purposes only, it is NOT intended to diagnose, treat, cure, or prevent any disease. Neither is it intended as a substitute for the advice provided by your physician or other healthcare professional. Do not use the information provided in this article for diagnosing or treating a health problem or disease, or prescribing medication or other treatment. Always speak with your physician/healthcare professional before taking any medication or nutritional, herbal or homeopathic supplement, or using any treatment for a health problem. If you have or suspect that you have a medical problem, or need urgent care, contact emergency services promptly. Do not disregard professional medical advice or delay in seeking professional advice because of something you have read in this email.




Natalie Woodman
Natalie Woodman

NATALIE WOODMAN is a Holistic Nutritionist and Naturopath, affectionately known as the ‘Gut Engineer’ owing to her intimate knowledge of the Digestive System and its workings. Her focus is on Gut (Digestive) Health and the restoration of the Gut Microbiome in the prevention and treatment of numerous health conditions.

  1. This is really dangerous advice. While a lot of this article is scientifically sound and informative there are some issues. Vegans and those on a whole food plant based diet should take a daily supplement – a cheap and reliable way to prevent b12 deficiency- it is water soluble so no risk of toxicity. As you noted the symptoms of deficiency are nothing to sneeze at and these symptoms are often irreversible. Advising only to take a supplement if very low is a bad idea as many may show symptoms before they appear clinically low. Foods such as yeast and spirulina are NOT active or reliable forms of b12 (unless that yeast is fortified). Please revise your advice. Kind Regards, Rhianna (accredited dietitian)

    1. Hello Rhianna, Thank you for reading my article. As I said…”If you are TOTALLY plant-based (i.e vegan) then you should be tested regularly (and not just B12, iron too)”

      I am telling people to see a Doctor and have blood tests, so that the Doctor – taking into account a patient’s full history (e.g. other conditions (MTHFR gene, Pernicious anemia, dietary requirements etc) – can deem was it a ‘low’ levels for them. In some cases, doctors will prescribe in a medium-low range. A doctor, not me nor you, should advise … “you’re vegan so take a B12 supplement” in the face of no data. There are always so many other factors to consider when a patient presents with a list of symptoms. And as you know, the symptoms of B12 deficiency can be attributed to many other conditions.

      The article clearly states.. “Get tested” – WHY? To rule out other conditions. And also, recent research shows some evidence that B12 supplementation may be associated with an increase in cancer risk in some groups – e.g. a 30% to 40% increase in lung cancer risk among men. So why wouldn’t you get checked regularly?

      Also if you read the article you will I say “Choose Fortified in B12” – And, for the record, Spirulina does contain a small amount of vitamin B12 active in the binding of the intrinsic factor. And research has shown that raw seaweed nori sheets (purple laver) has biologically-active B12 and is considered to meet the 2.4 μg daily requirements.

      And in closing…. while anecdotal evidence, I know, I have worked with over 100 vegan clients and a vast majority (while not all) have been able to improve B12 status with foods – paying careful attention to their dietary intake. I know this ‘dedication’ is not always the ‘norm’ which is why I say GET TESTED and also the recommendation of a sublingual spray if required.

      But again, thank you. It is great to see your passion for your clients. Natalie x (and I will certainly clarify in the article ‘again’ to GET TESTED REGULARLY so that it clear)

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