Vitamin B12 2024 – Why You Need It & Sources

Between 1-6% of people in the UK are deficient in B12. According to NHS GP Dr Ayan Panja, who explains that Vitamin B12 deficiency can occur even when someone’s blood results come back in “normal” range. The problem is that the tests do not look at the functioning level of B12 in the cells, only in the blood serum.  Also, what may be “normal” for one person may be low for another.  There are other tests that can indicate someone’s levels of B12, such as the Organic Acids Test that I use for my clients. Or, by measuring homocysteine levels which are inextricably linked, high levels of homocysteine raising concerns around both B12 and folate.  But why is B12 so important?

What do we need B12 for?

B12 is an important nutrient for making our DNA, regulating the building blocks that make us and is crucial for the functioning of the cells of the central nervous system.  Deficiency can lead to significantly reduced energy levels, difficulty with detoxification and neurological symptoms.

Source of B12

So where does B12 come from?  Well, B12 is made via bacterial fermentation.  The bacteria that B12 is produced from exist in abundance in the gastrointestinal tracts of animals, which originates from the soil they ingest.  This is why animal sources of B12 are the most bioavailable form, particularly meat, poultry, eggs and fish.  But even animals nowadays are supplemented with B12.  Dairy produce is much lower in B12.

picture of sauerkraut in a mason jarVegan and vegetarian diets

So, where can vegetarians and vegans get reliable sources of B12 from?  Well, fermented foods such as sauerkraut, kimchi, vegan kefir, miso and tempeh are also good sources. Also, sea vegetables (from a clean source) are a great source.  But essentially, in order to ensure you are taking in enough B12 as a vegan or vegetarian, you should be supplementing.  B12 can be stored in the body for long periods, so deficiency symptoms may not become apparent for at least 3 years after someone becomes vegetarian or vegan.

For those of you who aren’t vegan or vegetarian, particularly if you are suffering from fatigue, cognitive problems, diabetic neuropathy, viral hepatitis, anaemia or a neurological disorder, B12 is a must to get tested for. Because, whilst you may be getting sufficient amounts in your diet, you might not be able to absorb it. Particularly if you have low stomach acid (one sign of which can actually be heartburn) or pancreatic insufficiency (signs of which may be difficulty digesting fats).  In fact, so many people nowadays are placed on Proton Pump Inhibitors such as Omeprazole (almost all of my clients who come to see me with health conditions are on Omeprazole!) that this is certainly a consideration, as these drugs reduce the amount of stomach acid.

Picture of digestive systemMedication and B12

Those on metformin or potassium supplements are also a risk group and those of us over 60 are at even greater risk.  Anyone with a history of alcohol abuse, gastric or bowel surgery or Coeliac disease should also ensure they get their levels checked.  Also, doses of 500mg or more of Vitamin C taken with meals can limit our uptake of Vitamin B12, so if you are on high dose Vitamin C supplements, take them at least 2 hours away from your B12 supplement.

B12 supplementation

But how reliable is supplementation?  Well most problems with B12 arise from an impaired ability to absorb nutrients from food, such as with pancreatic insufficiency, low stomach acid or conditions such as Coeliac and Crohns Disease.  So supplementation is not always very effective.  But taking a sublingual form (ie it is absorbed under the tongue) can be much more efficient, and a good daily supplemental dose would be 1000µg.  It certainly isn’t sufficient to rely on the amounts in multivitamins, so I suggest all my vegan and vegetarian clients take a supplemental dose as multivitamin tablets do not provide B12 in sufficient amounts.

The most readily utilised forms of B12 are methylcobalamin and hydroxycobalamin and sublingual supplements that contain both are a good choice.  However, some people may be more suited to methylcobalamin and others more to hydroxycobalamin. It depends on their own individual biochemistry. So, it’s always worth working with a practitioner who can look at the whole picture. This is where lab testing and genetic testing can be particularly useful to tailor someone’s health and wellbeing programme.


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