Vitamins and minerals must all be broken down in our digestive tract in order to be usable, or bioavailable, to our bodies. This usually entails simply being chewed in our mouth, churned in our stomach (think cement mixer!) and meeting the right enzyme (think Tinder!!). However, Vitamin B12 must go through a more complicated metabolic process in order to become bioavailable. So, if our digestive system is compromised for any reason, or if we have conditions such as Pernicious Anaemia, Crohns’ Disease, Coeliac Disease or Helicobacter Pylori, then this vital vitamin will be more difficult to make use of, than other simpler ones. This is why the importance of vitamin B12 and the potential for misdiagnosis needs to be highlighted.  Vitamin B12 deficiency is something that we should all be aware of, because it can have such serious consequences. It is particularly important to monitor, if we have digestive issues, are vegan or are ageing.

The alternative is potentially experiencing a wide range of symptoms from mental health, neurological, vascular and other issues (symptoms table attached). Among its other functions, Vitamin B12 is involved at a cellular level in energy production. In order for our cells, (which make up our tissue, which makes up our organs) to function properly, they naturally need energy.

Consequences, Signs and Symptoms
When B12 deficiency attacks the body, it can take the form of any combination of symptoms in the table. However, these symptoms can also relate to other conditions, such as Multiple Sclerosis, Parkinson’s Disease, Dementia and other Neurological Disorders. If you are experiencing any of these symptoms, when you have your blood test, you should ask your doctor to rule out B12 deficiency, which is very easy to treat with regular injections or supplementation.

Potential Complications of Diagnosing B12 Deficiency
A blood serum test measures the level of B12 in your blood serum. According to research and studies compiled in the book “Could It Be B12?: An Epidemic of Diagnosis” by Sally Pacholok R.N. B.S.N and Jeffrey J Stewart D.O., the current B12 serum blood tests’ acceptable lower levels are too low. Click here for link to my interview with Sally. Due to the fact that deficiencies begin to appear in the Cerebral Spinal Fluid below 550pg/ml, Pacholok and Stewart believe that it actually should be at least 550pg/ml. For brain and nervous system health and prevention of disease in older adults, their research indicates that serum B12 levels should be maintained at a higher level.

These valid questions over what constitutes a normal range should be addressed because the risk of people remaining undiagnosed and symptoms progressing until they are have caused irreversible neurological damage, due to a Vitamin Deficiency, is unthinkable, and yet it is happening. There is a movement in the USA and the UK which is lobbying for the lower level to be increased to 550pg/L. In fact, in Japan it has already been increased to 500pg/L, which is quite a bit higher than the lower range of 150ng/L range. (Note 1pg/L = 1ng/L)
Note that currently according to the Mayo Clinic Medical Laboratories, the ranges are as follows:
Serum Vitamin B12 level <150ng/l = Deficiency
Serum Vitamin B12 level 150-400 ng/l = Borderline and requires further functional tests

However, Doctors must of course diagnose in accordance with the current guidelines. So, with this blog, I would just like to create awareness that the lower levels may need to be reconsidered. Please don’t diagnose yourself, in case there are other root causes, but if you are experiencing symptoms, consider your gut health, perhaps see a Health Practitioner, get your bloods checked by your GP, tell them about this research and talk to them about supplementation and increasing your serum levels above 550ng/L (or 550pg/L) if they are lower. There are further tests such as Methylmalonic Acid (MMA) Test, which can be used in conjunction with your blood test if needed.

Food Sources of Vitamin B12
As this is a water-soluble vitamin, we need to ingest a food source every day and ensure that our digestive system is functioning properly, in order to maintain our levels of this crucial nutrient. We can only absorb the form of B12 found in animal protein and so meat, poultry, fish, eggs and dairy products are good sources. This is why it is really important for Vegans especially, to supplement every day. It can take many months after changing to a Vegan diet for the symptoms of deficiency to manifest and so, people may not correlate how they are feeling with the absence of animal protein.
(Note – if supplementation is required due to malabsorption, ensure that you use a sub-lingual spray with an unbound form of B12 – hydroxycobalamin or methylcobalamin).

When it comes to producing energy, B12 does not work alone! It works along with B6 (Potatoes, Purple fruits, green vegetables, brown rice, avocado, soybeans, banana, prunes) and B9 (Legumes, vegetables especially leafy greens, citrus fruit).

Our Health is Our Responsibility
Modern medicine is amazing! However, we need to educate ourselves and take as much responsibility for the maintenance of this wonderful machine that carries us through our lives, as we would for our cars for example. In other words, mind yourselves!  Click here for a link to my web page with much more detailed information and resources for your information and please share it!

Sources: Gould & Dyer 2011, Pathophysiology for the Health Professionals, Pacholok & Stewart, Could It Be B12? and

For more information about this and the various studies supporting this view, visit this link please.

Lyn Sharkey Nutrition
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