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B12 Deficiency: What Everyone (Especially Vegetarians) Should Know


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Eating seafood—like this platter of lobster, clams, and fish—is an easy way to avoid a vitamin B12 deficiency.
Eating seafood—like lobster, clams, oysters, and fish—is an easy way to avoid a vitamin B12 deficiency.

Are you a dedicated vegetarian or vegan? Perhaps you decided to follow a plant-based diet to improve your health but over time you’ve started to experience troubling symptoms such as brain fog, fatigue, poor memory, and even numbness or tingling in your hands and feet—issues you never had previously. If you can relate, then you may have a vitamin B12 deficiency.

Research indicates that vitamin B12 deficiency is far more prevalent than previously estimated, with at least 40 percent of Americans demonstrating suboptimal levels, and millions more going undiagnosed altogether. The consequences of B12 deficiency are serious and can cause irreversible damage if left untreated.

Read on to learn about the health implications of B12 deficiency and why it is significantly underdiagnosed, the best methods for testing your B12 status, and how to optimize your B12 intake with food and supplements.

What a B12 Deficiency Means for Your Health

Vitamin B12 works with folate to synthesize DNA and red blood cells and assists in the production of myelin, which protects your nerve cells (neurons) and regulates nerve impulse transmission. A deficiency of vitamin B12 can have significant health implications for multiple body systems.

Vitamin B12 deficiency is exceedingly common—especially if you’re following a vegan diet. Find out how to tell if you have a deficiency and learn how eating nutrient-dense foods can help you correct it. #nutrientdeficiency #vegetarian #vegan

The classic association of vitamin B12 deficiency with macrocytic anemia, a condition in which red blood cells are larger than normal due to impaired cell division, speaks to the importance of vitamin B12 for regulating DNA synthesis. However, anemia is but one symptom of B12 deficiency. There are many other B12 deficiency symptoms that occur long before anemia sets in, including:

  • Dementia
  • Cognitive decline
  • Memory loss
  • Brain fog
  • Depression
  • Cardiovascular problems
  • Peripheral neuropathy (numbness, tingling, burning in the hands, legs and feet)
  • Impaired immune function
  • Infertility
  • Developmental and learning disabilities

Unfortunately, many of these symptoms are often mistaken for other health conditions, including Alzheimer’s disease and multiple sclerosis. As a result, B12 deficiency is often missed by physicians in the clinical setting, with serious implications for patients’ long-term health.

If You Have an Undiagnosed Deficiency, You’re Not Alone

B12 deficiency is far more common than most healthcare practitioners and the general public realize. A study from Tufts University found that 40 percent of people between the ages of 26 and 83 have plasma B12 levels in the low normal range, a range at which neurological symptoms can occur. Nine percent had an obvious B12 deficiency, and 16 percent exhibited “near deficiency.” (1) Surprisingly, the researchers also discovered that low B12 levels were just as common in young people as in the elderly.

Given the prevalence of B12 deficiency, why aren’t more clinicians and health organizations drawing attention to this serious problem? The answer lies in the fact that B12 deficiency is significantly underdiagnosed. Here’s why it’s frequently missed:

  1. B12 status is not routinely tested by most physicians.
  2. Serum B12, the conventional marker of B12 status, only drops in the later stages of B12 deficiency. Relying on serum B12 testing misses many, if not most, people who have an insufficient B12 intake.
  3. The low end of the laboratory reference range for serum B12 is too low. This is why most studies underestimate the true levels of deficiency.
  4. The standard serum test for B12 measures the total amount of B12 in the blood but does not rule out functional B12 deficiency. (A “functional” deficiency means that B12 levels are too low for optimum health, but symptoms like anemia may not yet be apparent or diagnosable.) (2) The determination of functional B12 deficiency requires other measures that are infrequently used by physicians.
Together, these factors mean that the current standard for B12 testing, serum B12, only picks up a small fraction of people with B12 deficiency. This has serious implications for the neurological, cardiovascular, immune, and reproductive health of people of all ages.

New and Improved Testing Methods for B12

Fortunately, new, more sensitive tests for B12 deficiency are now available, including tests for methylmalonic acid (MMA) and holotranscobalamin II (holo-TC). Studies using these improved methods of B12 assessment reveal much higher levels of deficiency than studies using only serum B12 testing.


MMA is a compound in the body that helps with metabolism, via a vitamin B12-dependent enzyme; if MMA levels are high, it suggests that vitamin B12 is lacking. There are two ways to have MMA measured: in the blood serum and in the urine. (3) Some experts believe that urinary MMA is superior to serum MMA as a biomarker of B12 deficiency because MMA is more concentrated in urine than in the blood. However, elevations in urinary MMA can also be caused by kidney dysfunction. Serum MMA, on the other hand, can be elevated in the presence of small intestinal bacterial overgrowth.

If you decide to undergo MMA testing to determine your B12 level, your current health status matters. I recommend urine MMA if you have SIBO, whereas serum MMA is a better option if you have a history of kidney dysfunction.


B12 is transported around the body by two proteins: transcobalamin II (TCII) and haptocorrin. Eighty percent of B12 is bound to haptocorrin, while only 20 percent is bound to TCII. Holo-TC, the marker that measures TCII, falls almost immediately after B12 intake drops. Serum B12, by comparison, measures total cobalamins (a name for cobalt-containing compounds, like B12). But it measures mostly haptocorrin, and doesn’t decrease until B12 deficiency has been going on for some time.


Homocysteine is an amino acid in the blood. It’s a marker of B12 deficiency when elevated, though not exclusively. Elevated homocysteine can also be caused by folate and vitamin B6 deficiencies. Homocysteine is more sensitive than serum B12; however, if it is high, you will need additional testing to determine whether the cause is B12, folate, or B6 deficiency.

Holo-TC, MMA, and homocysteine are considered measures of functional B12 deficiency because they reflect whether B12 is being appropriately utilized in the body.

Your Best B12 Testing Option

So, which one of these markers is best?

  • Holo-TC is the earliest, most sensitive indicator of B12 deficiency.
  • Urinary MMA and homocysteine typically don’t become elevated until the mid to late stages of B12 deficiency.
  • Serum B12 is the least sensitive indicator and usually doesn’t fall until the final stage of B12 deficiency.

While holo-TC testing is often the best way to catch an early B12 deficiency, it isn’t widely available in the United States (though it is in Europe). Here, we generally rely on a combination of serum/urine MMA, homocysteine, and serum B12 testing.

If you choose to get a serum B12 measurement, you will need to refer to a different range than the one provided by the lab when interpreting your results. Although most labs define deficiency at <200 pg/mL, it is well documented that many people experience signs and symptoms of B12 deficiency at levels between 200 pg/mL and 350 pg/mL. (4) Also, be aware that a high serum B12 does not necessarily rule out a functional B12 deficiency, which is best detected with MMA or holo-TC.

The same is true for homocysteine. The lab range often goes up to 15 nmol/L, but research has shown that a homocysteine level of 10 to 15 nmol/L is a substantial risk factor for heart disease, and that relationship is linear—the higher the homocysteine, the higher the risk. (5)

The Earlier You Notice a Deficiency, the Better

There are four stages of B12 deficiency, and the earlier B12 deficiency is detected in the progression of these stages, the more likely it is that the symptoms can be prevented or reversed.

Stages I and II

During the first two stages of a deficiency, your plasma and cell stores of B12 become depleted, and the concentration of holo-TC is reduced. Holo-TC is the only available marker for assessing the first two stages of B12 depletion. It’s likely that you won’t experience any noticeable symptoms if you’re in stages I or II.

Stage III

This stage of functional B12 deficiency is characterized by elevated homocysteine and urinary MMA concentrations in the blood. Serum homocysteine and serum/urine MMA are the best markers for detecting Stage III deficiency. At this stage, some people will experience mild symptoms like fatigue or brain fog, but others may not notice any signs or symptoms.

Stage IV

If you’re in the fourth stage of a deficiency, you’ll experience clinical signs, such as anemia, fatigue, and brain fog. Serum B12 and other markers of Stage IV deficiency may not decrease until this point. For some Stage IV patients, the cognitive and neurological symptoms are so severe that many believe they have Alzheimer’s or Parkinson’s disease. (6)

As you can see, signs like macrocytic anemia and symptoms like peripheral neuropathy or brain fog do not appear until the final stage of B12 deficiency. Stages I and II of depletion can precede deficiency (Stages III and IV) by months or even years!

To complicate matters further, the physical manifestations of B12 depletion can take years to appear. In the case of neurological symptoms, it may be too late to reverse them by the time the late stage of deficiency has been reached. (This particularly serious for children and young adults whose brains are still developing, as well as any adult at risk for Alzheimer’s or dementia.)

That’s why an early diagnosis of B12 deficiency is crucial.

What Is a Normal B12 Level?

As I mentioned before, the cutoff for serum B12 of 200 to 230 pg/mL, used by most studies and labs, is too low. Other studies suggest that B12 levels greater than 400 pg/mL, double the accepted lower limit of normal, boost the beneficial metabolic effects of B12 and prevent neurological damage.

Importantly, research also indicates that at least one-third of B12 in serum is not cobalamin, the metabolically active form of B12 in humans, but corrinoids, which are not metabolically active. This profound finding means that some people with “normal” serum B12 may actually be deficient because the test is counting metabolically inactive corrinoids as B12.

As a rule of thumb, if your serum B12 level is between 200 and 350 pg/mL, B12 deficiency may be a problem. Just remember that a normal serum B12 does not rule out functional B12 deficiency, which can only be assessed with holo-TC, MMA, and homocysteine.

If You’re a Vegetarian or a Vegan, You Should Be Concerned about B12 Deficiency

Vitamin B12 is found almost exclusively in animal foods. For this reason, vegetarians and vegans are highly prone to B12 deficiency. While early studies showed that vegetarians and vegans had only slightly higher rates of deficiency than omnivores, these studies used relatively insensitive markers, such as serum B12, and less stringent cutoffs for holo-TC, MMA, and homocysteine.

The newer, more sensitive measures of B12 status indicate that the prevalence of B12 deficiency is much higher in vegetarians and vegans than previously believed.

For example, one study that used serum B12 (the less sensitive method) indicated that 7 percent of vegetarians and 52 percent of vegans were B12 deficient, whereas when holo-TC was used, deficiency was detected in 77 percent of the vegetarians and 92 percent of the vegans. (7, 8)

Essentially, conventional B12 testing is missing 70 percent of vegetarians and 40 percent of vegans that are B12 deficient! This is a massive oversight that may have devastating consequences for the long-term health of both vegetarians and vegans.

Interestingly, I have noticed in my clinic that other signs of B12 deficiency, such as elevated mean corpuscular volume (a marker known as MCV), can be obscured in vegetarians and vegans. This occurs because vegetarians and vegans often have iron deficiency and a high folate intake; these factors lower MCV and effectively “cancel out” any increase that B12 deficiency would cause. (9) Calcium deficiency, which is common in vegans, can also lead to B12 deficiency because free calcium is required for the absorption of B12. (10) The possibility of multiple nutritional deficits is just one reason to think twice about following a vegetarian or vegan diet.

Omnivores: You Need to Pay Attention to B12, Too

While rates of B12 deficiency are much higher in vegetarians and vegans than in omnivores, that doesn’t mean it’s rare in omnivores. Approximately one in 20 omnivores is B12 deficient. (11) B12 deficiency is also more common in people with risk factors like:

  • Gut problems that decrease intestinal absorption of B12
  • Past or present use of gastric acid-suppressing medications, metformin, or antibiotics
  • A history of miscarriage and infertility

Vegans: You May Need More Supplementation Than You Think

Proponents of vegan diets promote B12 supplementation as the solution to B12 deficiency. However, supplements do not always solve the problem. In fact, research indicates that even well-educated vegetarians and vegans are not supplementing adequately!

Presumably well-educated vegetarians and vegans at a summer camp in the Netherlands were found to have serum B12 levels less than 200 pmol/L, a level associated with reduced DNA synthesis and other harmful metabolic effects. In another study, vegans taking B12 supplements demonstrated a paltry average level of 192 pmol/L.

Furthermore, the rate of B12 deficiency in vegans who supplemented with B12 was higher than in vegans who didn’t supplement! It is not clear why vegans who supplemented had higher levels of deficiency, but it could be due to the interference of supplemental B12 with active B12 levels. (12) In both of these studies, the subjects were from vegetarian/vegan societies and thus likely to be better educated than the general population. However, this did not prevent them from having a B12 deficiency. (If you need help choosing proper supplements, see the last section of this article for more specifics.)

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Your Kids Need B12 throughout Childhood

Women who consume vegetarian and vegan diets during pregnancy and breastfeeding and families that feed their children vegetarian and vegan diets during infancy and childhood are playing with fire and increasing their children’s risk of serious developmental and health problems.

Vegetarian Moms: You Need to Get Enough B12 during Pregnancy

If you’re pregnant and you have a B12 deficiency, your child could have low B12 throughout infancy and childhood. The longer a mother has been a vegetarian, the higher the likelihood she’ll have low serum and breast milk B12 levels that correlate with a deficiency in her infant. (13, 14, 15)

High homocysteine resulting from low maternal B12 status may promote neural tube defects and congenital heart defects in utero. (16)

The Impact of a Deficiency for Your Child

The prevalence of B12 deficiency is 67 percent in American children, 50 percent in New Zealand children, and 85 percent in Norwegian infants who have followed vegetarian or vegan diets their entire lives. (17) This is extremely concerning, as B12 deficiency can have “extensive, severe, and irreversible” consequences for brain and body development in children. (18)

B12 deficiency impairs fluid intelligence, spatial ability, and short-term memory in children; in fact, vegan children score lower than their omnivorous peers in all of these areas. (19)

B12 deficiency in children leads to:

  • Poor school performance
  • Depression
  • Weakness
  • Fatigue
  • Nerve damage
  • Failure to thrive

Even if a vegan or vegetarian child switches back to a diet that includes animal products, they may not be able to reverse all of the problems that come with low B12. A study of kids raised on a vegan diet found that they were still B12 deficient years after they started eating animal products. (20)

That means compromised B12 status in childhood may have negative consequences that extend well into adulthood. (21, 22)

B12 deficiency also has serious health repercussions for adults. Notably, it raises homocysteine, a risk factor for cardiovascular disease, dementia, and Alzheimer’s disease. (23) Ironically, many vegetarians and vegans choose a plant-based diet to reduce their risk of cardiovascular disease, yet several studies have shown that homocysteine levels are higher in vegetarians than omnivores and higher in vegans than vegetarians. (24) Vegetarians and vegans with low vitamin B12 status are at risk of developing circulatory health problems regardless of their favorable profile of traditional heart disease risk factors. (25)

What to Do If You Think You Have a Deficiency

The first step I recommend is to get a holo-TC and/or urinary MMA test. If either of them is abnormal, you should immediately take steps to increase your B12 levels. There are two ways to do this:

  1. Eat B12-rich foods
  2. Supplement

How to Get More B12 in Your Diet

B12 contains a trace element (cobalt), which is why it’s also called cobalamin. Cobalamin is produced in the gut of animals and is found almost exclusively in animal foods. Some of the best sources of B12 are:

  • Liver
  • Clams
  • Oysters
  • Mussels
  • Fish eggs
  • Octopus
  • Fish
  • Crab and lobster
  • Beef
  • Lamb
  • Cheese
  • Eggs

A common myth among vegetarians and vegans is that it’s possible to get B12 from plant sources like:

  • Seaweed
  • Fermented soy
  • Spirulina
  • Brewer’s yeast
The truth is, there are almost no vegan sources of vitamin B12.

Nearly all seaweed tested has been revealed to contain vitamin B12 analogs (that is, chemically similar) called cobamides that block the intake of—and increase the need for—true B12. (26) The one exception is a combination of dried purple laver (nori) and wild mushrooms, which were shown in one study to reduce MMA.

Using a Supplement

Cyanocobalamin is the most frequently used form of B12 supplementation in the United States. But recent evidence suggests that hydroxocobalamin is superior to cyanocobalamin, and methylcobalamin may be superior to both—especially for neurological disease. This is because methylcobalamin bypasses several steps in the B12 absorption cycle and, unlike cyanocobalamin, readily crosses the blood-brain barrier. (27, 28) On top of that, methylcobalamin provides the body with methyl groups that play a role in various biological processes critical to overall health.

We now know that the dose of B12 in a supplement needs to be 100 times higher than the RDA of 2.4 micrograms/mL to be effective (this comes to approximately 250 micrograms/day). If you’re deficient, your dose should be even higher, at approximately 500 micrograms/day.

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Join the conversation

  1. Can nerve conduction study show nerve damage due to vitamin b12.
    I had severe vitamin b12 deficiency 76pgml.
    It was untreated and undetected for over an year.
    I have all the symptoms of nerve damage .
    My shoulder and back pain is constabt since 1 year.
    Can anyone please help which test can confirm nerve damage and on which body part should it be done.
    For eg: i have pain in my shoulder and back.so should it be done there.?.
    Please notify me at [email protected]

  2. Can nerve conduction study show nerve damage due to vitamin b12.
    I had severe vitamin b12 deficiency 76pgml.
    It was untreated and undetected for over an year.
    I have all the symptoms of nerve damage .
    My shoulder and back pain is constabt since 1 year.
    Can anyone please help which test can confirm nerve damage and on which body part should it be done.
    For eg: i have pain in my shoulder and back.so should it be done there.?

    • I was measured at 40pgml after being ill for about 2 years, i had all of the symptoms of nerve damage in my hands and feet and was in receipt of hydroxycobalmin injections for about 5 years which only brought my levels up to 330pgml. I was still severely symptomatic, nerve problems, pains, numbness and tingling and brain fog and fatigue.
      I started doing a B12 sublingual along with a Bcompelx that contains methlyfolate(metafolin) rather than folic acid among other things (fish oils, adB12, gamma E complex).
      within 3 months my levels were at 850 and almost all the symptoms were gone including the depression that had plagued me for years. i’m going to be taking these supplements for life but if i don’t feel the way i did before then its worth it!
      hope this helps and you get better

      • Hello Deborah. I’m sorry, I know you posted this two years ago. I hope you get this and are able to reply. I am 42 years old (female), . Army Veteran. Experiencing almost the exact symptoms as you for the same duration (over 2 years). Some of mine are: Upper back pain, constant pain in shoulders, cold hands and feet, peripheral neuropathy in feet. Muscle spasms in legs, weak legs, brain fog, insomnia (every single night), twitching thumb (occasional), eyelid use to twitch but not anymore, occasional numbness in arms and legs, chronic fatigue, depression, extreme constant pain inside both feet (in wheelchair most of the time because of this), pressure in chest occasionally. Doctors haven’t been much help. Numerous tests have come up normal so now they just want to prescribe anti depressants for fibromyalgia. So i am doing what I can to help myself. I was wondering if you can tell me the exact supplements you took and the mg/dosages. I have been doing so much research, and I am still reading up on Freddd’s recovery protocol. So I will be taking dibencozide b12, desiccated liver pills, methylb12, b complex (methylated), methylfolate, cod liver oil, activated charcoal, lecithin. And a multivitamin that also has b vitamins for methylation as well. I do still have silver amalgams in my teeth so I am suspecting mercury toxicity/poisoning. So I have to schedule with a biological dentist to get them removed. Since u almost had full recovery I was wondering if u could please please break down your protocol on what you used and what mg and dosages. I am trying to acquire all the help I can get. I really appreciate it if you can. Thank u.

        • Two things come to mind. . . tics and twitches can be a sign of magnesium deficiency. Also, activated charcoal will adsorb and attach itself to anything ingested at the same time, so take it at different times than your supplements or medication.

  3. I’m confused. What does it mean when you have high levels of Vitamin B12 with supplementation? Tested at 1665 pg/ml. That’s with 5,000 sublingual methyl supplementation. I read Chris’ comment about a high level ‘without’ supplementation so i wonder if a high level WITH supplementation is expected. How can we know for sure if the body is absorbing B12?

  4. Hi I’m going for an active B12 test next week as my GP has moved my jabs to 2 monthly in past year and when I was having them weekly by week 5 I was just starting to feel some change and by week 15 I was feeling quiet a bit better not perfect or as I used to be but at least 75% better. Then my bloods came in at just over 900 and GP basically thinks I’m cured so moved them to 2 monthly and I got to nearly the second week and all my symptoms was back but seemed worse than before (they probably wasn’t but as I had not had most of them for sometime I think they just seemed worse) and I spent several nights sobbing and wishing I had never ever had the jabs as I would not have felt what it was like to be somewhat normal. It’s taken me a year to get a different GP to agree to refer me for active test (of which I have had to pay for but a small price if it shows that a lot of my b12 is not active then I have something to argue with). I just want my life back as much as possible.

  5. Hello Again, I am referring to Nature’s Way potassium chelated which you have recommended. Thank you.

  6. Hi Chris, Can you recommend another potassuim chelated as I am grain free and this contains millet. thank you.

  7. Oh and my blood work also said I had low iron saturation (13 and should be 20-50) and my iron was very near the bottom of the range (42 in a range of 37-145) and my urine showed a small amount of leukocyte, elevated RBC, elevated WBC and elevated epithelial cells, although the doctor said none of this was enough to worry about…is it?


  8. Hi!
    I’m 57 and recently started feeling sickly; brain fog, no energy, no interest, no concentration, very winded after climbing stairs, problems sleeping, bowel urgency. Went to an RA and he tested me for autoimmune because I always get a + ANA (1:160) and my B12 was almost 1,200. I asked him why and he said not to worry about it (I don’t supplement). So he sent me on my merry way. I know through 23andme I’m also heterozygous for the C677T (as well as several other MTHFR genes that I know nothing about, but not the A1298C). I’m also heterozygous for several of the MTR genes (which I understand have something to do with B12). I also had 3 miscarriages due to high antiphospholipid antibodies (but I now test negative) and was diagnosed with a vascular disease (eyrthromelalgia) about 5 years ago. I was scheduled for surgery last week due to calcification on my shoulder that caused a full tear and separation in my supraspinatus rotary cuff tendon and I can’t raise my arm over my head anymore, but I postponed it because I do not want to go into any kind of surgery not feeling strong and healthy (plus I’d have to wear a sling for 6 weeks…yuck!). I’m going to see an integrative doctor next week and hope he can give me some answers. Just wondering…does anyone think that MTHFR could have anything to do with the calcification? Thanks!

    Also…loved and am sharing the video about low b12!

    • Hi carol…I have all same symptoms as yourself and more. I also could not raise my left arm above my head….it was very very painful, very very stiff and also hard to shave under my armpit. The specialist I saw just wanted to inject it with steroids which I refused as I know family and friends that have had similar (but in different joints) and steroid injections have not worked, or have taken a month to work then only last a month. I just every day slowly raised my arm as far as I could then bounced it gently (until I got a bit if pain and uncomfortableness) and now I can fold my arm behind my head and almost raise it to where I could in the past. Also I have in last 6months or so got severe pain in my left foot, just had X-ray to check no breaks but doc thinks plantar facilitus. Everything with me seems to be more isolated down my left side. Also at mo I have quiet a bad pain in my left lower back area (feels like a urine or bladder infection but I know it’s not…so don’t know wat that one is).

    • I had the same problem. I could only lift my left arm to the level of my shoulder. I had been to the GP, did the MRI, he suggested surgery and I passed, so sent me to PT, which did nothing. When reading about histamine intolerance, I came across Frozen Shoulder which is caused by a reaction to citrus. I eliminated ALL citrus from my diet and my armed went back to normal within 3 weeks (after not working for 4 years). That was a year ago and I can still use my arm. I doubt surgery would have given me the same results. I’d love to know if you consume a lot of citrus.

      • Hi Ann,

        I don’t eat a lot of citrus. That’s great that you figured out what was causing yours. I’m going to look into that a bit more and see if it is something I’m eating. I had no idea the calcification was forming until it was so large that it would catch on the bone when I tried to raise my arm and by that time it has already caused a full tear of the tendon.

  9. Hi Everybody,
    I am from India, male 35 , 110 Kg Weight , 5′ 11” got recently tested vitamin B12 with 160 pg/ml (Picograms per milileter) ?
    How much medication of Methycobalamine Injection or HydroxyIcobalamine Injection I should take per day till how many days for replenishment?? What happen if i took excess medication??
    You can advice me any other options if necessary…
    Looking forward for your reply.

  10. Are the co-factors necessary in the supplementation of B12? Or can just the methyl B12 be taken for good effect?

    • Hi Derek. I know you posted this 2 years ago. I just stumbled upon this page. Maybe you already found your answer. If so, you can disregard. You can Google: how I recovered Active b12 therapy and methylation faq. Or Google: Freddd’s Methylation protocol. These should help you with the co-factors.

  11. I have a rare genetic condition (Ehlers Danlos Syndrome) where I get severe joint pain – to the point where I can’t get out of bed some days. However since starting a mostly plant based diet (I eat meat maybe once or twice a week (hormone, antibiotic free from a local farmer)) and going vegan in other aspects and doing the whole organic local thing I seem to be getting somewhat better.
    I am concerned because my family has a history of B12 deficiencies. I take pills and I am looking at getting shots done soon (I take so many pills for my illness that I often forget to add in my vitamins.) after approval from my specialist.
    My question is what else can I do to help the B12 be absorbed – since this is a family problem. I can not eat anymore meat without potentially compromising my health.

  12. Hi, I am a lacto-ovo-vegetarian for 7 years, did my blood test, everything is fine except b12(holotranscobalamin is 20 pmol/l, where normal value stated is >=50). I started taking a total of 1000mcg/ day orally a month ago. Please tell me if this should work and how soon should I test the active b12 in my blood again. Please help me, my doctor barely knows anything about the subject.

    • After 2 month of taking oral cianocobalamin (1mg/day),I tested again, my levels were 128 (above 50). Now I just take 1mg/week so that it doesn’t go down again.I hope my experience with this helps others too.

      • My doctor didn’t know much about b12 in general, but after research on internet, I found a local lab that had the test on their list (I’m from Romania). It cost me around 20 euros and it came back in about 10 days because they sent it to a lab in Berlin, as it stated on the result sheet.

  13. 29 years ago my husband had 18 inches of colon removed and was told he would need B12 because his body would no longer manufacture it. Several years later a new doctor said he did NOT need the shots and no other doc has suggested them since. So Chris, do you have a perspective on that? I am primarily vegetarian, he is a meat eater.

  14. Does there always have to be a systemic cause for B-12 deficiency for non-vegetarians? I was just tested and have a very low 189 for B-12. I have had some “buzzing” and “tingling” like sensations but my energy, focus, etc. is fine. I was shocked it was this low. My doctor says it could be celiac or PA and ordered a bunch of tests. Does anyone else have unexplained B-12 deficiency after ruling out more sinister causes?

    • Hi.
      I had my level at 76pgml.
      I was shocked too and so were the doctors.
      I have always been a non vegetarian.
      I’m taking 1500 mcg methylcobalmin injections/day now.
      your levels aren’t very low though,still you should consult a good doctor.
      He’ll help your better.
      Peace and good health.

    • Hi Caroline, I have unresolved B12 deficiency which is neither PA or Celiac. It is frustrating not knowing the cause.

      I made my first post 18 & also 30 July so really new at this.

      How are you getting on now?
      Good luck,

  15. Hi, a good friend of mine has been having injections for some time now because He has b12 deficiency, He gets terrible, no energy and to be honest he looked terrible.

    I buy vitamins such as multi vitamins in spray form, I told him to this a try http://sprayavit.net/product/vitamin-b12/ as I find there products very good, since He has been using the spray He seems much better and doesn’t have so many injections.

    Possibility worth checking them out?

  16. Can you advise a specific sublingual or best supplement for vegetarian children? Thank you in advance!

  17. Does anyone have thoughts on the MegaFood brand of B12? I have been taking it because it’s a whole foods derived vitamin and I also like what I read about the company (non GMO, etc). My concern is that Chris mentioned that yeast derived B12 is not effective, and as I understand it this company feeds B12 to s.cerivisiae. Thanks.

  18. Most interesting info, ‘wrong.’ I look forward to learning more about B-12 in the human diet.

    I want to report preliminary results of my personal ‘test’ of the precise B-12 supplementation regimen Chris recommends. I ordered and received the four (4) supplements: B-12; Potassium; Folate; Trimethylglycine (TMG). I take one each daily after breakfast. It has only been a few days since I started, but I have a few observations: 1) I seem to have more energy; 2) I’m more alert and my concentration has improved noticeably, a big plus if in fact this is due to the added B-12 supplementation; my digestion perhaps has improved slightly; 3) improvement in mood stability, again not sure if this isn’t due to something other than the added B-12, in fact not sure of any of this very early results. It will be interesting to track longer term changes in mental and physical health. I’ve added the same measures to my daily chart.

    One result, having to do with tolerability taking the supplements. The first day I took the B-12 first and almost immediately felt queasy. This unpleasant feeling lasted a few minutes. I hesitated taking the remaining 3 supplements, and didn’t take them until a few minutes later, after which the queasy feeling in my stomach abated. The next day and since I take the other 3 supplements first, Potassium, Folate, and TMG, and wait 5 minutes before putting the B-12 lozenge under my tongue, where it remains until fully dissolved, a process which takes several minutes to complete.

    Finally, I have noticed only a slight change in the color of my urine, a faint yellow, after taking the supplements. I don’t know if this is due to the slower and presumably improved absorption of B-12 into my system, but I thought it worth noting since my prior experience with B-vitamins I have had a marked yellowing of urine.

  19. You are wrong, chris :


    “UK official recommendations have decreased in recent years, the body’s needs having been previously over-estimated. Indeed, the Department of Health recognises that some people have lower than average requirements of B12. A whole lifetime’s requirement of B12 add up to a 40 milligram speck of red crystals, about one-seventh the size of an average tablet of aspirin!

    Vitamin B12 is excreted in the bile and is effectively reabsorbed. This is known as enterohepatic circulation. The amount of B12 excreted in the bile can vary from 1 to 10ug (micrograms) a day. People on diets low in B12, including vegans and some vegetarians, may be obtaining more B12 from reabsorption than from dietary sources. Reabsorption is the reason it can take over 20 years for a deficiency disease to develop. In comparison, if B12 deficiency is due to a failure in absorption, it can take only three years for a deficiency disease to occur. Since vitamin B12 is recycled in a healthy body, in principle, internal B12 synthesis could fulfil our needs without any B12 being provided in the diet, but there are other factors to be taken into consideration such as whether there is sufficient cobalt, calcium and protein in our diet to ensure a stable vitamin B2 level and the condition of our intestines.”

  20. OK, I’ve ordered the full complement you recommend via your links. Up until now I’ve been taking Solgar B-complex “50” solo to supplement my 1Xday multivitamin. I’ll see what difference(s) there might be in the way I feel taking the poly-supplementation versus the mono-supplement B-12 complex.

    I’m retired and living on a restricted fixed income, hence I need to make careful choices with as low a price for the best quality supplements I can afford. Your 4-supplements cost me more than twice what my present 1 supplement costs. So I will be alert for positive and negative effects on how I feel overall.

    I take a Consumer Reports highly recommended Multivitamin Senior Formula 1 X day. My only other supplements are a C complex, D-3. Finally an Omega-3 fish oil supplement made by Nordic Naturals, or OmegaBrite, as adjunct to the prescription medicines I must take for severe Bi-Polar Depression. The Omega-3, by the way, has been a real life-saver for me, as its positive effects on mood are palpable and reliable. They get me through the more depressed periods I periodically encounter in my mood cycles.

    Thanks again for your marvelous website. It’s a g-d-send to know where to go first for good health advice and recommendations.