B12: your life depends on it

There are very few nutrients as crucial to our well-being as vitamin B12. The reason why this is so is that vitamin B12 is essential for cellular energy metabolism, gene transcription, and nervous system function. This vital role at the cellular level is not restricted to only some tissues and organs: it is vital for every single cell of every tissue and every organ.

For the nervous system, both for the central nervous system—our brain—and the peripheral nervous system—the spine and entire network of nerves connected to the brain and coursing through the whole body—vitamin B12 is essential in building, maintaining and repairing the myelin sheath that covers every nerve to ensure protection and proper nerve signalling. It is, in fact, the consequences of B12 deficiency on the nervous system that most often betray this very serious problem.

Everyone should supplement and maintain blood levels of B12 in the range from 600 to 2000 pg/ml in order to avoid and, if this is the case, help recover from the wide range of problems that result from B12 deficiency or insufficiency. Health care practitioners: this is the first thing you should check for every patient that comes in, independently of their age or condition.

What is vitamin B12 and how is it absorbed?

B12 or cobalamin is a large molecule whose central atom is cobalt, and around which are arranged various other compounds. To be active in the body, the cobalamin molecule must be in one of two enzyme forms: methylcobalamin or adenosylcobalamin, both of which must be in a charge state of +1. Even though cobalamin can exist in two other charge states, +2 and +3, neither of these is bio-active. Its most powerful antagonist is nitrous oxide (N2O; laughing gas), which continues to be commonly used as an anaesthetic agent during surgical operations, because it inactivates the molecule by modifying the cobalt ion from a charge state of +1 to one of either +2 or even +3.

Cobalamin is produced in the gut of animals by specific bacteria that make part of the intestinal flora. Although this can also be true for humans, we have mostly relied on animals both by eating them and products derived from them, like eggs and dairy. In animal foods, cobalamin is always bound to protein from which it needs to be separated in order to be used. This, in turn, can only be done starting in the highly acidic environment of a well functioning stomach that secretes enough hydrochloric acid, but also enough Intrinsic Factor and pepsin.

Cobalamin is carried into the duodenum—the first part of the small intestine—by salivary B12 receptors that are then broken down by pancreatic protease. This allows the free B12 to attach to Intrinsic Factor, and make its way to the ileum—the very last part of the small intestine—where it penetrates the mucosal wall for absorption. Finally, the free cobalamin latches onto the plasma transporter Protein Transcobalamin II whose function it is to carry it to the cells throughout the body. Any excess, unneeded at any given time, is carried to the liver where it is stored.

Where do we get B12?

That herbivores like sheep, goats and cows, which thrive when they eat only grass, do not suffer from B12 deficiency, but that most of us humans tend to (estimates from various large scale studies range between 40 and 80%), points to two key issues at the heart of this problem:

One, we have evolved and survived as a species over several million years by eating animals. It is believed by some that it was, in fact, the very eating of animal foods, maybe specifically bone marrow, which was, on the one hand, the only left overs after carnivore predators like lions, and then all other scavengers but predators for us like wolves and jackals had eaten all they could, and on the other, the only thing that only humans could get to by breaking apart the bones, that allowed the brain to grow in size over a relatively short evolutionary period, seting us apart from our our primate ancestors and cousins. Whatever the case may be, the organism of the human species as a whole grew accustomed and became reliant on an external supply of vitamin B12 from animal sources.

Two, it is most certainly the case that even with the healthiest, let’s even say ideal or perfect intestinal flora, as humans we will definitely have a very different flora than those of the herbivore animals we domesticated, and it will arguably always be much less capable and much less efficient at producing cobalamin from any of the plant foods we do eat. Moreover, if B12 is manufactured by some of the bacteria in our perfectly healthy colon—the large intestine, it will still not easily make it into circulation because, as we saw, absorption of cobalamin takes place in the ileum in the last part of the small intestine, which is upstream from the large intestine. The manufactured B12 would somehow have to migrate backwards from the colon to the ileum, a most likely very difficult thing to do.

The first point is supported by ample archeological, anthropological, as well as evolutionary biological evidence. In fact, it turns out that our hominid ancestors have most certainly lived for the bulk of our evolutionary history during periods of glaciation where the land over most of the Earth’s surface was covered in ice. This implies that there was a marked absence of plant life in most places on Earth, and therefore an absolute reliance on animals for survival, eating virtually only animals, which in turn also ate virtually only other animals and fish, which ate smaller fish, and on down the food chain to those feeding on sea-borne plant foods. The Inuits, who basically live on whale blubber, are the perfect example of such a scenario. But this could well have been the scenario for a lot of the humans that populated the Earth, and for a good portion of our history spanning the last 2.5 million years.

The second is hypothetical, but on firm footing given that it is indisputable that the gut flora of a herbivore will be different—substantially different—from ours, but also that we simply cannot survive for very long on greens alone as do sheep, goats, cows and all other herbivores. Furthermore, in actual fact, most humans have a dysfunctional digestive system, with heavily compromised and impaired intestinal flora. As a consequence, even those who eat adequate or even large amounts of B12-rich animal foods, usually cannot benefit from it because the cobalamin simply doesn’t make it into the bloodstream for any one of several possible impediments along the ingestion-breakdown-absorption chain.

This is not to say that our digestive flora cannot produce some B12 from plant-based foods, but the evidence shows us that it definitely cannot produce enough, whatever the reason: studies have shown that although B12 deficiency is of the order of 40% in the general omnivore population, it is 50% in vegetarians, and up to a staggering 80% in long-term vegans (see Chapter 6 of Could it be B12? and references therein).

Why is B12 deficiency such a big deal?

Well, let’s ask another question instead: What would happen if the myelin sheath that covers the nerves in our body—peripheral, spinal and brain—were to deteriorate?

Neurological symptoms would include: numbness, tingling and burning sensations in the hands, fingers, wrists, legs, feet, or truncal areas; Parkinson-like tremors and trembling; muscles weakness, paraesthesia and paralysis; pain, fatique and debility labelled as chronic fatique syndrome; shaky legs, unsteadiness; dizziness, loss of balance; weakness of extremities, clumsiness, twitching, muscle cramps, lateral and multiple sclerosis-like symptoms; visual disturbances, partial loss of vision or blindness. But the list goes on.

Psychiatric symptoms? Confusion and disorientation, memory loss, depression, suicidal tendencies, dementia, Alzheimer’s, delirium, mania, anxiety, paranoia, irritability, restlessness, manic depression, personality changes, emotional instability, apathy, indifference, inappropriate sexual behaviour, delusions, hallucinations, violent or aggressive behaviour, hysteria, schizophrenia-like symptoms, sleep disturbances, insomnia. And here again, the list goes on.

At the cellular level, every cell would be unable to adequately produce energy, be it from glucose or from fat. We can easily extrapolate and imagine what it would mean for the organism as a whole to have a lack of, or severe debility in the energy available to it at the cellular level, and this, for the trillions of cells throughout. This would have a most profound effect on everything that we do, and everything that the body does throughout the day and night.

Now consider a yet deeper level: in the nucleus of every cell, where genes are protected and cared for, a problem in the very transcription and replication of genes—these delicate operations that are necessary and vital for the continual renewal, repair and reproduction of cells—which must and do take place throughout our life, this long succession of infinitesimal instants the perception of which is almost universally absent from consciousness, but for which the timescale is, in fact, very long at the cellular level, where movements and interactions take place at phenomenal speeds. Vitamin B12 is absolutely essential for this too. And if it’s missing? Unintended, unplanned, and unwanted genetic mutations from errors in transcription. This means problems; very serious problems.

Who should be concerned about all this?

The short answer is: everyone. This means you, but also your kids as well as your parents. It means infants, toddlers, children, teenagers, young adults, mature adults, the middle aged, the elderly, and the oldest among us: absolutely everyone.

For the longer answer, it would appear to be the case that we are, or at least should be, born with a good B12 reserve, and that, as it is used over time, the amount in the body and blood slowly decreases as the reserves get used up and eventually depleted. Some consider this to be the normal state of affairs. This inevitably implies that those at greatest risk of suffering from B12 deficiency are the oldest, and also that the older we get, the greater our chances of becoming victims of the effects of this deficiency. And this is indeed what we find: practically everyone above the age of 60 is B12 deficient, and more often than not, severely deficient (serum B12 < 200 pg/ml).

It is therefore not really surprising that every single behavioural characteristic—intellectual, psychological, emotional, physiological and physical—associated with ageing and its multiple manifestations in the elderly, senior moments in all their different forms: memory problems, disorientation, inability to concentrate or even pay attention, frailty, weakness, unsteadiness, loss of balance, etc, etc, are all typical  symptoms of B12 deficiency.

Could it be that all these characteristics of old age are actually the characteristics of B12 deficiency? Could it be that if we didn’t let B12 levels drop below 600 pg/ml and actively maintained them around 1000 pg/ml throughout life, that seniors would simply not manifest any of these signs of old age? Maybe. Maybe even most probably. What an entirely different world it would be: strong and healthy, energetic and vibrant, sharp and alert old people. Sounds great, doesn’t it? And hard to imagine, isn’t it? But wouldn’t that be wonderful, for everyone, and especially for the elderly themselves?

As alluded to a moment ago, we should be born with a large B12 reserve. It is of particular importance that we need to have a plentiful supply of B12 throughout our development in the womb, during infancy, and up to the 7 years of age. Why is it so important? Because our nervous system develops fastest while we are in our mother’s womb, and then during infancy and as a toddler, until it reaches maturity by the time we are about 7, and because cobalamin is essential for this development.

The complication, however, a point of crucial importance, is that only B12 consumed by the pregnant mother at first, the breast-feeding mother afterwards, and finally by the toddler can be used to ensure an optimal development and building of a healthy brain and nervous system. Even if the mother had good B12 levels before, during and following pregnancy, only fresh B12 can be used in the developing child. So, if she doesn’t consume much or any during this critical period, the unborn child and infant will have only a meagre or non-existent supply of cobalamin, and consequently, impaired—often severely—brain and nervous system development.

This is a very serious matter. In fact, for many infants, it is a matter of life or death. Or just barely less dramatic but maybe even worse in some respects, it can make the difference between a normally healthy brain and nervous system, and permanent developmental disability, both physical and intellectual, right down to a full or partial vegetative state for a whole lifetime.

All of this shows why B12 deficiency tends to be not only transmitted, but to worsen in severity from one generation to the next, with all the negative consequences that come with it, but most notably those that affect the brain and all cognitive functions. Terribly sad and unfortunate as it is, numerous studies and reports on the babies of vegetarian but especially vegan and macrobiotic mothers have shown very serious neurological problems, developmental delays as severe as stunted brain growth and death, but also that even mild deficiencies in infancy are associated with seriously impaired cognitive performance in adolescence and adulthood. I cannot stress this enough: B12 deficiency is really very serious.

Now, between the oldest and the youngest there is everyone else. If we are born with an excellent B12 status, then we are lucky and likely to be able to make it to old age without any apparent problems in this regard. If we are born B12-deficient, then we are most certainly likely to suffer from it greatly, and this, much sooner than later. And if we are born with anything in between, an intermediately good or bad B12 status, then problems will appear later in life, or sooner, depending on many other factors, but most importantly on how much cobalamin we consume, and how well it is absorbed. Consequently, manifestations of cobalamin deficiency can appear at the age of a few months or a few years; as a child or teenager; as a young adult or person in their prime; near retirement or in old age; or it may also never become apparent. Unfortunately, this condition is continuously growing in importance, the people it affects growing in number, and the reported cases growing in severity.

Unfortunately, and extremely sadly for way too many people whose bodies, minds and lives are destroyed by an undiagnosed deficiency, B12 is not something that doctors routinely check or know much about. Most of them believe that it will appear in the total blood count (TBC) panel either as enlarged (megaloblastic anaemia) or fewer red blood cells (pernicious anaemia). But by the time you get there, you have been suffering the ravages of B12 deficiency for a while already, and have thus almost certainly also already suffered permanent neurological damage. So, for your sake, don’t wait for your doctor to notice this. Instead, teach them about it. You will be doing them and their patients an immense favour.

Closing with the good news

It is really easy to prevent and avoid becoming cobalamin deficient, but also to correct a deficiency that exists or even one that has persisted for several years or decades, no matter if you eat animal products or not, want to or not, think that you should or not. We must, very simply, check our B12 status regularly by measuring three markersserum B12, plasma homocysteine (Hcy), and urinary methyl-malonic acid (MMA)—and make sure to supplement in order to raise and maintain B12 levels in the range between 600 and 2000 pg/ml, with concentrations of Hcy and MMA as low as possible. Pregnant and nursing mothers should maintain levels above 1000 pg/ml to ensure healthy nervous system development in their children.

(Both Hcy and MMA are toxic byproducts of protein metabolism that must be converted to benign and/or useable forms, the animo acid methionine, for example, by the action of B6, folic acid (B9) and especially B12. Here is a good information-dense compilation of B12/Hcy/MMA publications, and transcript of an interview with John Dommisse, a psychiatrist and B12 expert, who published the above quoted serum B12 range as optimal in this authoritative paper cited in Could it be B12? where I read about it.)

Supplementation should be with methylcobalamin—not cyanocobalamin—and should be as aggressive as needed depending on the result of the assessment. In cases where B12 levels are below 200 pg/ml, we should request methylcobalamin injections to be administered daily for 5-6 days, and then weekly until B12 reaches 2000 pg/ml. It should be maintained there at least until Hcy and urinary MMA have dropped significantly, and then monitored and maintained around 1000 pg/ml.

For anything else between 200 and 600 pg/ml and/or elevated Hcy or MMA, methylcobalamin patches are an effective way to get B12 levels up. In addition, oral supplementation, although the least effective of the three, still works surprisingly well compared to other supplements, and obviously cannot possibly hurt; it can only help. I recommend doing both patches and oral supplements until levels are around 1000 pg/ml, and then maintaining them with either one.

Finally, and very important to know is that you cannot overdose on methylcobalamin B12: not one negative physiological side effect has been reported or is known from methylcobalamin supplementation. You cannot do yourself or anyone any harm by taking B12 as methylcobalamin in large quantities for a long time; you can only do yourself and others harm by allowing a deficiency, as mild as it may be, to develop or linger. This applies to everyone.

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30 thoughts on “B12: your life depends on it

  1. Dear Guillaume,
    I’m new to your blog, and I congratulate you for a job so outstanding and so well done! I’ve been reading your articles and I’m enormously impressed by your obvious talent to “digest” a complicated subject matter (as everything concerning our physiology is) and come up with a clear and concise summary! It’s a pleasure to read your posts, I find them critically important, as it only recently dawned on me (I’m 57 yrs. old and caring for my mother at home near Toronto) how dangerous it is to be ignorant and to surrender one’s health and well being to doctors and specialists. If I had obeyed my Doctor’s repeated advice, I would have been on a statin for 10 years today. I’m glad I had the sense to flatly refuse. And this is only one of a dozen such examples in my experience.
    Anyway, to keep my post brief: Thanks to your posts on B12 I changed my mother’s supplement. For years she’s been getting monthly injections of Cyanocobalamin, which we now stopped. Instead, she and I are both taking “NAKA Nutri B-50 Complex liqiud” which includes 1000 mcg Methylcobalamin, plus an additional daily 1000 mcg sublingual (both Jamieson and SISU offer that formula). I trust this change to be beneficial for both of us.
    Thank you for your superb blog!
    Toni (Vlado’s sister and Vassko & Lucy’s friend)


    • Thank you. I am very happy that you find it useful and interesting. I’m also glad you refused the statins (did you read my posts on cholesterol?) As for the B12, I would recommend using patches because they are more effective at getting the B12 to the blood without any losses due to digestive processes, and they are easier to “take” because you only need stick them onto your skin somewhere and forget about it. Do you or your mom have any specific issues I can help with?


      • Hi Guillaume,
        Thank you for your reply! I actually researched the market for B12-patches, but couldn’t find a reliable product. I will look again. I’m very grateful that you so kindly offer your advice, and I’m struggling to keep my post as short as possible. My mom’s (85 yrs. old) situation first (I’ll take better care of myself later). 1. Major event: In her 40-s she had a stomach (duodenum) ulcer operation, 2/3-s of her stomach was removed, resulting in Dumping syndrome. Meals are small, frequent, very selective (cannot tolerate fried, spicy, sour, milk, etc.) Food absorption (even in healthy people!) is questionable, but I hope her system has adjusted as best as possible during all those years since. 2. Hepatitis C from blood transfusions in the hospital after the operation (in the early 1970’s blood wasn’t being checked yet). Resulting Liver Cirrhosis, which we’re checking twice/year and the Gastro-specialist keeps describing her liver as “stable, but not very happy”. 3. She was still in Europe during Chernobil (early 1980’s), and like many others, her Thyroid was affected. On Synthroid/Eltroxin since 1994. Did Radioactive Iodine treatment (2002). Only recently did I read some very important books on the topic and am now aware of the huge controversy of Synthroid vs desiccated thyroid. Family Doctor is going by the TSH result (even Free T4 and Free T3 are not measured standard anymore), and I now know that that’s an unreliable test. The Doctor (I guess they have their Regulatory bodies to consider) refuses to even discuss switching the synthetic drug to the natural desiccated thyroid supplement. Hired a Naturopath who is able to provide the supplement, but it’s a very complicated issue (adrenal fatigue has to be ruled out, etc.) and having to do tests repeatedly is a challenge (my mom is frail). So the thyroid is “Work In Progress”. 4. Osteoporosis: Was on the drug Actonel for 11 years and stopped it last year when side effect was experienced first-hand (diminished lower jaw bone mass, which is now a big problem as the lower denture is loose and it greatly affects my mom’s chewing/eating ability). 5. Diabetes: On Metformin for 3 yrs. now. Fairly good control, last month’s Glucose Serum Fasting is 7.1 and Hemoglobin A1C is 0.069.
        In general during the last decade my mom has been bothered by dry skin, itchiness (during the night, or early morning), waking up with slight headaches, brittle nails, thin hair, mediocre energy level, balance problems, gradual weight loss, swollen ankles and/or tummy, constipation and haemorrhoids – all could be from the thyroid and/or from the liver. Ten years ago the Dermatologist diagnosed “Lichen sclerosus et atrophicus” (pearl-white spots on the skin, like a rash, Doctor said cause is unknown and young people get it, too). Another important point is that my mom’s cholesterol according to the guidelines is fine, meaning low – and only recently did I come across in my readings on the topic that it is actually dangerous, especially for elderly ladies, to have low cholesterol!
        Anyway, for the sake of brevity – to point out my main worry today from the most recent blood tests:
        Liver AST (Reference Range 7-31 U/L) was 49 High (May/’13) and 45 High (Dec./’13).
        Liver GGT (RR 12-43) was 136 High (May/’13) and 111 High (Dec./’13) – suspected Bile Duct Inflammation/disorder (???)
        The following were tested at 2 different labs which utilize slightly different Reference Ranges (common occurrence):
        Hemoglobin 121 (RR 115-155) (Nov./’13) and 115 Low (RR 120-160) (Dec./’13)
        Hematocrit 0.37 (RR 0.33-0.45) (Nov./’13) and 0.34 Low (RR 0.35-0.45) (Dec./’13)
        WBC (White Blood Cell Count) 4.6 (RR 4-11) (Nov./’13) and 3.9 Low (RR the same 4-11) Leukopenia Neutropenia (Dec./’13)
        RBC (Red Blood Cell Count) 3.69 (RR 3.6-5.01) (Nov./’13) and 3.58 Low (RR 4-5.1) (Dec./’13)
        MCH 33 High (RR 27-32) (Nov./’13) and 32.1 (RR 27.5-33) (Dec./’13)
        RDW 15.7 High (RR 11.5-15.5) (Nov./’13) and 15.3 High (RR 11.5-14.5) (Dec./’13) This test has been elevated for some time: 14.6 High (May/’13) and 14.8 High (June/’13)
        Neutrophils 1.75 Low (RR 1.8-7) (Nov./’13) and 1.6 Low (RR 2-7.5) (Dec./’13)
        Platelets 93 Low (RR 145-400) (Nov./’13) and 98 Low (RR 150-400) Decreased Moderately (Dec./’13). When I looked back, Platelets have been too low for quite a while (108 in June/’11).
        I recently read that Platelets below 100 is dangerous (internal bleeding is mentioned). The Doctor, however, never mentioned anything about low platelets – is it not indicative of something malfunctioning or something developing, or some deficiency? Could it be that unimportant? But then why bother measuring it?! I guess these days patients have to actively participate in healing themselves.
        Following your advice, my mom (like Vlado) started taking Prescript-Assist a month ago. She’s also on Synthroid and Metformin, Vit.B-Complex Liquid, additional B12 sublingual, Omega-3 alternating daily with Cod Liver Oil, Vit.D3+Vit.K2. The Naturopath prescribed “Thorne S.A.T.” (Liver support) and “Os Matrice” (Osteoporosis) but my mom stopped taking both, as she became overwhelmed by the number of pills to take. I’m worried about the drop of the white blood cells and her thus diminished immune system. I’m sorry about the way-too-long post, it’s like a detective story – given some clues it’s a real challenge to figure out what the main problem could be.
        Thanks a million, Guillaume, take care,


      • Dear Toni: thanks for your trust. Let’s start with the five most important things to do:

        First, from the textbook example symptoms and blood test results, your mother is definitely iron deficient as well as zinc deficient. This is easy to take care of because it just involves take these as supplements. I recommend Mercola’s Zinc complex and Thorne’s Bisglycinate, every night after the evening meal. B12 patches you can order from Dr David’s Patches. Take the original 1 mg with extra vitamins, stick one on every day for 1 week, and then 1 per week.

        Second, the liver is an extremely important organ and we must focus on this to get it in good shape fast. The very best thing for healing the liver is green juice fasting. Start with one complete day per week (24 hours). The next week do two complete days, and repeat this every week thereafter. My wife and I do this every week, and there is hardly anything better for super boosting health. You can make her 3 juices per day following the recipe I sent to Vlado (or something similar), definitely with the coconut milk so that we are never hungry, really.

        Third, water and salt are the most important elements for life. Read this and this. Every day, prepare 2 bottles of 1 litre each with 1/2 to 1 teaspoon of unrefined atlantic sea salt dissolved in each litre. She must drink this every day. All other drinks, including green juices and teas are on top of this. Also, give her cucumbers with salt every day. The total of liquids (and cukes) must be 3-4 litres each day. This is necessary to flush out accumulated acid and toxins and heal the kidneys.

        Fourth, you must eliminate all insulin-stimulating (simple and starchy) carbohydrates from the diet for ever. Read this and this, but I would recommend you read through the entire archive of the articles I have written. It is only then that you will understand the extent to which carbohydrates are terrible. Anyway, this will fix her diabetes, water retention in the ankles, and every other metabolic problem that stems from long term consumption of carbs.

        Fifth, replenishing magnesium is extremely important for everything, and it super easy. Read this and this. Make your mom take a hot bath (not too hot: 41C) with 1 cup of dissolved nigari flakes three times per week.

        Get going on these 5 things as soon as possible. The sooner the better. Be very strict and I guarantee that the positive change will be amazing, and this, within weeks. I would also recommend stopping the meds gradually: decrease dose, then frequency, then phase out. Drugs are always poisonous. And keep me updated about the progress in 2-3 weeks.


      • Dear Guillaume,
        Just a quick line to say “THANK YOU!!!” so much for your post, I appreciate it greatly! I need time to get organized, order supplements and plan/prepare/start implementing a few new things, but I’ll report back to you in due course. Best Regards, Toni


      • Dear Toni, how are things going with you and your mom? I haven’t gotten word from you or your bro in a while. Have you implemented any of the suggestions I made? Have you seen changes and improvements? If this is the case, could you please take the time to recount the process of how you went about it and what happened on the page devoted to testimonials?


      • Dear Guillaume,
        My apologies for taking so long to report back… it’s all due to a complex household workload made more difficult by the harsh winter, plus some computer/operating systems headaches, but I’ll email an update asap.
        Best for now,


  2. Hello Guillaume
    Thank you so much for writing these articles — very informative!
    I do have a question, if you don’t mind. I have my mother’s test results for B12 and thought I would take a look at where she is on the scale and if there is room for improvement but the measurement seems to different ie: you quote values in pg/ml whereas the lab results for my mother are quoted as pmol/L where 220=sufficiency. Is there a conversion formula?
    Thanks so much for being available to answer questions; it’s very much appreciated!


    • Good morning: The conversion factor for B12 is 1.35 pg/ml = 1 pmol/l. The reference values that appear on your lab results are 148 and 220 pmol/l, which correspond to 200 and 300 pg/ml (rounding for ease of memory). These are the old standards and are totally off the mark: This is part of the reason why so many people suffer from undiagnosed B12 deficiency. Because neurological disturbances appear at levels of 450 pg/ml (~350 pmol/l), this is the strict minimum we should maintain. Much better is to maintain levels above 600 pg/ml (~450 pmol/l) where no disturbances can be detected, and better still between 800 and 1000 pg/ml (~600-750 pmol/l) which are optimal. Remember that it’s important to also measure Homocysteine, and have it as low as possible.


  3. Dear Guillaume,
    I’m pasting here a paragraph from your response (for which I thank you!) to my post (June 30/’14) under “Testimonials”:

    “About thyroid health, I have unfortunately not yet written about this, but by far the most important supplement that everyone should be taking to ensure proper thyroid but also generally healthy glandular and hormonal function, is iodine/iodide. More specifically, either Lugol’s solution or Iodoral, in the amount of 50-100 mg/day for at least 6 months, and then 12.5-25 mg for maintenance (see Iodine: why you need it, why you can’t live without it). So, start taking 100 mg of Iodoral or Lugol’s per day (morning and noon) and ween off the Synthroid over a month of so. It is also much better to take ATP cofactors to help with the absorption of iodine. Both supplements are made by Optimox and available on iHerb.”

    My mom’s Thyroid gland was irradiated (more than 10 years ago). My understanding is that, although Iodine supplementation is very important for a Thyroid gland which hasn’t been treated with radioactive Iodine, in her case it apparently wouldn’t help. Apparently Synthroid provides the synthetic hormone T4 from which the body produces another important hormone, T3. My concern is that any pharmaceutical, especially taken for many years, harms the organism more than it helps. Also, with age progressing, the body most likely becomes more unable to convert the T4 into T3 in the required quantities. Therefore a lot of patients and some medical practitioners recommend desiccated Thyroid hormone (from pigs?) which, being natural, already contains both T4 and T3. Now, there have been issues with reliability and lack of consistent supply (different batches being with differing potencies), but from the little that I know on the whole topic thus far this problem has improved lately. My only concern (and what is actually stopping us to drop the Synthroid in favour of desiccated Thyroid) is that close medical supervision is necessary (incl. blood tests, etc.), which in our situation is quite difficult.
    I’m anxiously awaiting your article on the Thyroid gland, when you get around to it. Great many thanks!


  4. Dear Guillaume,
    Sorry for posting so much, but here’s something closely related to the B12 topic, namely Folic acid. I get a monthly B12-Methylcobalamin injection with 400 mcg of Folic acid. I just read somewhere that Folic acid (apparently increases the risk of cancer) is to be avoided in favour of Folate (5-MTHF) or Folinic acid. Do you have any thoughts on the issue, please?
    Thanks as always,


    • Hi Toni: I haven’t read about folic acid specifically. However, if you eat lots of greens and seeds, then you will have naturally very high levels of it. So, this is what I recommend: forget the shots and get B12 patches (much cheaper and just as good), and eat lots of greens and seeds. Simple, natural and effective.


  5. I notice you recommend B12 patches here, but somewhere else I think you recommended Dr Mercola’s sublingual spray. Is Dr. M’s spray okay?


    • Hi Maria: Yes, M’s sublingual is good as far as oral B12 supplements go, but it is much faster and more effective to use patches because virtually all of it goes into the body instead of only a fraction of it. I used M’s spray for months without much change in my B12 levels. Then I did a little more reading about it, and found that patches are the next best thing to intramuscular shots, which are cumbersome and more expensive. Hence, I started using patches for us at home, and, naturally, recommending this method to my readers.


  6. I won’t get into the details just yet, but I have neurological symptoms and suspect I have a B-12 deficiency. I have a second appointment with a neurologist in two days and I am not sure how to go about insisting that he order the tests –this is a leading teaching hospital in Atlanta, so my hope is that my idea won’t be poo-poo’ed Any guidance on how to talk to the doc respectfully is appreciated — he is young, which I hope is to my advantage! Thank you!!!


    • Dear Catherine: Is it not possible for you to find a private blood analysis clinic where you can go and ask them to do whatever tests you want them to? This is what I do here in Spain. This way you don’t have to deal with physician-ego problems in not knowing why you would want to have certain tests done. It is true that, following the descriptions in Could it be B12?, doctors tend to conspicuously neglect testing for it, and getting defensive when the patient requests it. So, this is my recommendation, download my essential blood test reference sheet and print it to take with you (either the PDF or the Google spreadsheet). Get all these tests done at a private clinic and hence bypass the need for the Doctor’s recommendations. Of course, they might be open minded and agreeable to ordering the complete set of these tests, but this is more the exception than the rule. Nonetheless, a friend and follower of this blog does have a personal physician who is like that; she even started following this blog and recommending it to her patients. So, you might as well try, softly, to not give the impression of being forceful and a know-it-all, which is a sure way to get them aggravated. Let me know if there is anything else I can help with.


  7. Guillaume, thank for responding. I saw the neurologist today and he still can’t find anything “neurologically” wrong with me. The MRIs were good and I “passed” all the tests the doctors do– again. He ordered the B12, MMA, Copper and Zinc blood tests and referred my to an otolaryngologist, `which is a neurologist who specializes in balance. I have several other symptoms, including clumsiness, tremor in my hands/feet, arms/legs, trunk/neck, and voice. I have muscle weakness, loss of muscle in my legs, weight loss, low appetite, and nausea. In December, when I first saw my primary physician, I had tingling, spasms and electric-like sensations in my legs. I am seeing a gastroenterologist for a colonoscopy and was wondering if I should ask him about absorption. Any thoughts?


    • Hi Catherine: I would have liked to see the results of all the blood tests I recommend as essential to get a complete picture instead of poking around here and there. Additionally, I would have ordered a hair mineral analysis to check out levels of heavy metals like mercury, lead and arsenic, which can bring on such neurological symptoms. What you list are all textbook severe B12 deficiency and/or Parkinson’s disease symptoms, but those are also seen in heavy metal toxicity or severe magnesium deficiency.

      What I would do if I were in your situation is to order some methylcobalamin shots online, two trays of 1 mg ampoules and one tray of 5 mg ampoules, and learn how to give yourself B12 shots. (It’s important to rule our mercury toxicity before injecting the B12 because it can apparently accentuate the toxicity in case of toxic levels of Hg.) I would give myself a 1 mg shot every day for a week, then drop to every three days for 3 weeks more weeks, and then wait a week, and go to one 5 mg shot per week after that: It is necessary to correct the B12 deficiency and then maintain very high levels for a long time (months to years) in order for the nervous system to recover.

      I would also take high dose Lugol’s iodine solution drops 50 mg first thing in the morning and 50 mg 30 minutes before lunch (on an empty stomach), high dose liposomal C (4000 mg/day; that’s 4 x 2 caps) and high dose liposomal Magnesium (3 x 2 caps; both are available from Mercola or on iHerb) after meals. To help pull out and excrete the heavy metals that are around, chlorella and spirulina taken together 2-3 times per day, gradually increasing the amount as the body gets more accustomed to them, and magnesium chloride and sodium bicarbonate baths (1 cup of each) every couple of days, soaking for 45-60 minutes. Hope this helps. Keep me posted.


  8. Unfortunately Dr.David’s Patches (for B12 and also other supplements) don’t seem to be available anymore… I looked a few months ago, and still today the site is “unavailable”, no trace of “Dr.David’s”. Wonder what happened?…


  9. Hi Guillaume,

    Please can you help my brother. Diagnosed with M.S for 20 years but getting so poory he can hardly leave his bed. I have read a lot about Pernicious Anaemia and he has so many symptoms I’m sure he has that as well. Our father had Pernicious Anaemia too. I haveThyroid trouble and my daughter R.A all auto immune as you know. I have ordered Sally Pacholoc’s book to try to understand more. I’m sure he only had a serum B12 test which gave a false reading as he was spraying B12 under just tongue. Please can you help I feel desperate for him.

    Thank you so much,


      • Regarding b12 methylcobalamin, I did not understand how efficient it is if taken under the tongue, and if 1000 micro grams a day is enough for an elderly with several illnesses but stable thanks to a holistic approach to meals and daily routine, and if not, how much the minimum should be in your opinion !? Thank you very much. Merci.


  10. Additional clarifications to the above post of mine: the elderly with several illnesses – 65% heart blood vessels clogging, spine deformation and several disc herniations, diverticular disease -has had rectal bleeding in the past, кidney cysts, but stable thanks to a holistic approach to meals and daily routine. The only chemical medications she is taking are Nevibolol for the heart and perindopril arginine/ indapamide/ amlodipine in medium high dose half of what doctors precribe for the blood pressure. I am also taking bisoprolol fumarate and the same perindopril arginine/ indapamide/ amlodipine in medium high dose half of what doctors precribe for high blood pressure which I have had rise above 95 and 140 since teenage-hood but started taking medication only a few years ago after seeing supposedly the best heart specialist in Bulgaria, previous to which I used to have severe head aches, and at the doctor s it turned out my heart had enlarged by 1/3 and aortic valve had expanded. Would be nice if you could advice on that. Merci.



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