B12: Everything You Should Know…But Don’t

By: Claire Georgiou, Reboot Naturopath, B.HSc ND

I often get asked by Rebooters, “Am I getting enough B12?” Well, let me break it down for you so you know everything there is to know about B12.

What is it?
Vitamin B12 (cobalamin), is a water-soluble vitamin that is made by bacteria with a key role in the normal functioning of the brain and nervous system, and for the formation of blood involved in the metabolism of every cell of the human body, especially affecting DNA synthesis and regulation, fatty acid synthesis, energy production and myelin formation. Myelin is insulation that protects your nerve endings and allows them to communicate with one another.

Vitamin B12 has been nicknamed the energiser, particularly in cases of stress, B12 deficiency, fatigue or recovering from an illness.

What are the top foods that have B12?
Non-Vegan: Meats, liver, kidney, egg yolks, dairy products and seafood
Vegan: Tempeh, kombu, nori, miso, spirulina, fortified foods and supplements.

NOTE: Plant based sources of B12 are generally not reliable and it is often recommended that vegans and certain vegetarians supplement to ensure adequate B12 levels. Many vegan health websites encourage people to take their B12 supplements as insurance.

What causes an increased risk of B12 deficiency?
Vegans and some vegetarians
Pregnancy and hyperthyroidism–
increased requirement
Elderly –
poor absorption
Pernicious anemia
– due to the destruction of the cells that produce intrinsic factor (autoimmune disease) which support assilimation of b12 in the stomach.
Gastritis, IBD, celiac and IBS
- impaired ability to absorb Vitamin B12
High Alcohol intake
– alcohol reduces absorption.
Some Medications
– used on a long-term basis can reduce the absorption of B12 such as – anti-acids, oral contraceptive pill (OCP), metformin, prednisone, antibiotics, large doses of supplemental folic acid and Vitamin C.
Helicobacter pylori
– some GIT infections can disrupt absorption.
High level of unhealthy bacteria in the intestine
– also known as dysbosis – this can reduce the absorption of B12.
Gastrointestinal surgery –
Gastric Bypass surgery or surgery that removes all of part of the stomach or ileum.

What are signs and symptoms of B12 deficiency?
It can take 1-5 years for a B12 deficiency to appear after the body’s supply from natural sources has been restricted.  If it is not detected in the early stages (<2 years), it may result in permanent neurological disturbances at levels only slightly lower than normal.

Signs & Symptoms : soreness and weakness in the legs and arms, reduce reflex and sensory response, tingling, numbness, difficulty walking or speaking, memory loss, weakness, fatigue, anaemia, hair loss, impaired touch or pain perception and burning in the mouth.

These symptoms will occur at varying degrees and combinations. Vitamin B12 deficiency can also lead to demyelinisation of peripheral nerves, the spinal cord, cranial nerves and the brain, resulting in nerve damage and neuropsychiatric abnormalities.

It can mimic Alzheimer’s disease, multiple sclerosis, early Parkinson’s disease, diabetic neuropathy, or chronic fatigue syndrome. It can make men or women infertile or cause development disabilities in their children.

It was found from the ongoing Framingham Offspring Study that an estimated 39% of the U.S. population may be marginally vitamin B12 deficient with plasma B12 levels in the “low normal” range–below 258 pmol/L. While this is well above the currently accepted deficiency level of 148 pmol/L, some people exhibit neurological symptoms in the higher range, said study leader Katherine Tucker.

How do I test for vitamin B12 deficiency?
A B12 blood test can’t always be a true indication as some inactive forms of B12 can still increase the blood result. Some reports suggest that homocysteine levels are a better indicator to the true level of active B12 (desirable levels are <10), although this indicator has poor specificity because it is influenced by other factors, such as low vitamin B6 or folate levels. Another test is elevated levels of serum MMA (Methylmalonic Acid)- (>0.4 micromol/L) an indicator for vitamin B12 deficiency.

Vitamin B12 reference range is around 130-850 pmol/L. This is an unsafe range as many in the population exhibit neurological symptoms of deficiency at much higher concentrations. The lowest concentration to be considered normal is 221 pmol/L. Even further studies indicate that it ideally should be above 350pmol/L. This can be evaluated along with other tests as indicated above.

B12 daily dietary recommendations – 2.4mcg-3mcg

Do I need to take a B12 supplement during a Reboot?
While completing a Reboot, it is not necessary to take a B12 supplement unless:
– You have been prescribed this by a healthcare professional
– You are vegan or vegetarian
– You don’t often eat many B12 rich foods

If you suspect you may have a deficiency or are experiencing any of the above symptoms then talk to your doctor about getting some tests done.

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Claire Georgiou, Reboot Naturopath, B.HSc ND

Claire Georgiou is an Australian Naturopath, Nutritionist and Herbalist who has completed a Bachelor of Health Science (Compl. Medicine) and an Advanced Diploma of Nutrition, Naturopathy and Herbal Medicine. She has more than 14 years of clinical experience specializing in liver disease, autoimmune disease, thyroid conditions, diabetes, insulin resistance, digestive disorders, chronic infections, children’s health, fertility and pregnancy care. Claire consults in private practice in Sydney and also offers consults out of area and is an accredited member of the Australian Traditional Medicine Society. Claire has worked closely for many years with Dr. Sandra Cabot, who is known as the “Liver Cleansing Doctor” and has written more than 25 health related books. Claire writes health related articles, creates healthy recipes and is one of the nutritionists who runs our Guided Reboot programs.

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