The People's Perspective on Medicine

Do You Know Your Vitamin B12 (Cobalamin) Levels?

Have you ever been tested for vitamin B12? Do you know the symptoms of a deficiency? This nutrient is essential for good health. Several drugs can lead to low levels. Are you taking one?
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Most people do not think much about Vitamin B12, also known as cobalamin. It does not get the attention of vitamin D, vitamin K or vitamin C. And yet this water-soluble nutrient is crucial for every cell in your body. Red blood cells require cobalamin. So do nerve cells. Without adequate levels of vitamin B12, people develop pernicious anemia. They may also experience neuropathy or nerve pain. The brain does not function well without adequate levels of B12. Sadly, though, many health professionals do not order vitamin B12 testing. That can lead to disastrous consequences, as this reader points out.

Nerve Problems from Vitamin B12 Deficiency:

Q. In 2016 I was admitted to the hospital with numbness in my groin, legs, arms and hands. A week of blood work and CT scans did not show a reason for the problem. After that week I was released with no treatment and no improvement.

I subsequently reviewed my blood tests and noticed that my vitamin B12 level was extremely low. I went to my primary care doctor who started giving me B12 shots.

The problem cleared up within a couple weeks. I continue the shots today and have had no further trouble with this.

Symptoms of Vitamin B12 Deficiency:

A. Inadequate vitamin B12 levels can trigger neurological problems such as numbness and tingling (BMC Research Reports, Sep. 18, 2015).  Vegans, who consume no animal products whatsoever, are at particular risk of this condition. Patients who have had gastric bypass surgery are also vulnerable to this vitamin deficiency and usually need supplements (GE Portuguese Journal of Gastroenterology, April 2018).

People taking powerful acid-suppressing drugs called proton pump inhibitors (PPIs) or the diabetes drug metformin may also be vulnerable to a cobalamin deficiency. We think people who take such medications should routinely get tested for B12 levels.

You might ask your doctor if you could switch to oral vitamin B12 supplements. Some research suggests that pills can be as effective as shots but less expensive (Cochrane Database of Systematic Reviews, March 15, 2018).

Other Symptoms of Low Levels of Cobalamin:

  • Anemia can manifest as pale skin and tiredness
  • Nerve damage (numbness or tingling in feet and hands)
  • Dizziness, fatigue, shortness of breath
  • Weakness, weight loss and depression
  • Irregular heart rhythms (arrhythmias)
  • Psychological side effects (mood changes, dementia)

How to Restore B12 Levels:

Lee points out some important caveats:

“Often there is a B12 deficiency due to lack of production of intrinsic factor in the parietal cells in the fundus of the stomach. I’ve observed doctors giving B12 shots when the root cause was stomach cancer, especially around the gastroesophageal junction.

“Taking proton pump inhibitors that suppress the production of stomach acid can also cause lead to low levels of B12. It is better to determine the cause of the deficiency rather than just supplement.”

Blood Tests Are Essential:

Ann in North Carolina encourages testing:

“I had problems after having been first on Prilosec and then Nexium for over 20 years. I was being treated for acid reflux. I literally crashed and burned because of pernicious anemia. My B12 level was very low. In addition to the numbness and tingling in my hands upon waking, I experienced shortness of breath and unbearable fatigue and weakness.

“My doctor finally tested for cobalamin. I had to get vitamin B 12 shots for a year. I also needed extra iron.

“I had been complaining for a decade that I was very tired all the time. I was told my thyroid was ‘normal’ which it wasn’t. Anything over 2 is too high for me and I was a 6! I went to an endocrinologist who tested my thyroid and discovered I had Hashimoto’s which was also wreaking havoc.

“I finally weaned myself off the Nexium due to the other problems associated with it. I continue to take Vit B12 liquid supplement, Vit D3 & CoQ10 since I’m on a low dose statin. Shame on these doctors who prescribe medications without following up with blood testing!”

Learn more about vitamins and testing in the book, Fortify Your Life by Tieraona Low Dog, MD. This is the best book on nutrients that we know of. You can listen to Dr. Low Dog and Dr. JoAnn Manson at this link.

They have differing perspectives on the value of vitamin supplements.

Share your story about vitamins in general and vitamin B12 in particular in the comment section below.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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The type of B-12 can matter as well as the lack of it. this applies to those with perncious anemia as well. There is a genetic Issue that some people, including myself, have an inability to process cyancobalamin as well as folic acid.

This variant is in 10-20% of the population from my research. It is called MTHFR. Cyancobalamin is synthetic. Metylcobalamin is the natural form. Folic acid is synthetic. Folate is natural. Finally, at an advanced age, due to my rising homocysteine, my integrative physician tested me for this genetic variant.

I have two genes of one form of it. This is linked to many many health conditions including autoimmune disease. You not only need to take the proper form of these two B vitamins, but avoid food products fortified with the wrong form. The US government started fortifying grains with folic acid in the late 1990’s due to birth defects caused by a lack of folate.

I have found coconut milk as well as some surprising foods fortified with folic acid or cyancobalamin. That addition could actually be causing health issues for some people. I finally feel great after years and years of health issues when I switched my multi vitamin to a MTHFR compatible multivitamin.

Anyone with pernicious anemia should consider using methycobalamin in sublingual form as well as methycobalamin injections instead of cyancobalamin.

I was under the impression ingested Vitamin B12 was inactivated by gastric acids, and we have always taken the sublingual version. Please discuss oral vs sublingual and the recommended dosage. (We take 1,000 mcg/day) Thanks.

Long story simplified, I complained for 8 years to my Dr about being exhausted, paleness, blue lips, joint pain, coldness, palpatations, heart murmur, he did all the heart tests and stress, test for legs to tell me I had raynaud’s disease, then I crashed hard, couldn’t stay awake, really blue lips, memory fog, everything felt like pressure and felt depressed but knew I wasn’t, called to make appt my Dr retired and who took his place did all the same tests but included b12 and D and low and behold, I was below 100 on my b12 and also D deficient!

All those years of suffering and I do not have raynauds! 4 years later and Still haven’t gotten to bottom of why but I take b daily I took enough to where my b was high so I stopped then crashed and burned again, so I must take it daily.

I’m only 52 now so it’s been a long journey and your never too young to get your b levels checked! Listen to instincts and don’t let Dr’s blow you off!

My name is Ruth. I’ve been having prediabetic symptoms. Tingling on my feet, numbness. I had this for five years now.

I have anemia once in a while. My red blood cells are low. My doctors r not doing nothing about it. But im readn. And I think I need B12.

How much is too much B12? How do you know if the amount you take is the right amount?

I started falling forward, not tripping, face forward. After 7 th time I went to dr, found nothing wrong. Like the others on here, never tested-b-12.

When I finally changed Drs and was tested i was at 69.should be around 900– I was given sublingual b-12 and plummeted to zero I now have to inject twice a week, I had stomach surgery and was told must keep b- 12 level at 1500+.

If not my stomach lining will thin out and bleed! I have severe nerve damage, peripheral neuropathy and am sick a lot. I was also on proton pump inhibitors which kill b-12. Sometimes the pain is horrid. I’m told the nerve damage from it getting so low is irreversible
PLEASE. Everyone at all ages should be checked.

D vitamin is and has been low too. Such a simple thing like a vitamin can ruin your life. Pain, numb,tripping and falling. Stomachache issues and more, All because they didn’t think of it !!! Sad

Doctors want Tell you this: while I was in hospital for 5 day, I had pneumonia, they gave me 2 different kinds of antibiotics.and when I was dismissed o was given another kind of antibiotics. 750 mg, I was told that my lungs was almost clear.

When I got home, my body was very tired. I was very nervous and had pain in my joints and bones. Shoulder were very painful hurting all the time I could not raise my arm to even comb my hair.

Long story short. Body stripped of vitamin B-12. Plus other things. Still trying too deal with other problems.

Also, if you already supplement with B12 or supplement right before your test for B12, your numbers will be high from the supplementation, not because it is truly high enough.

You should ask for a methyl malonic acid test which is the hallmark test for low B12. When your bodys is low in B12, it will try to create its own B12 and when it does so, your methyl malonic acid will be high. High MMA = low B12. I also suffered with low B12 but took a long time to find out because the MMA test wasn’t used.

Also, another time, my B6 was very high and when you have too much you will have the same neurological symptoms as low B12, but this vitamin can cause irreversible nerve damage. So if you have neurological symptoms have both of these levels checked.

Many years ago a doctor discovered from blood work that I had no vitamin B12 present in my body, blood and liver. She started me on monthly shots. I now take two B12 pills under my tongue daily. My B12 levels are good now. My daughter also has this problem of storing B12. We both have hypothyroid, and the lack of B12 goes along with it. So if you have a problem with the function of your thyroid it is wise to have your B12 level check.

I’ve been having severe weakness and numbness in my extremities going on for 3 years after having my gall bladder removed and many hospital stays, with some being in the ICU on life support. Just recently I was told by my hematologist that my B12 was low. I do and have been having problems with my blood platelet count being extremely low and they can’t find a diagnosis of the cause for this other than my bone marrow isn’t making enough. My question is this, can low B12 cause this to happen or can the low platelet count cause me to be low in B12? Or can both of these come from my surgery? I never had these problems before then.

I watched a docuseries on Alzheimer’s. A neurologist –Dr. Datis Kharrazzian [hope spelling correct] recommended a B 12 test measuring the amount within the cell. Saying the measurement in the blood does not always reflect that B 12 is being used.
Would be good to know more about that . Thank you

I read in a health magazine that METHYL cobolamin is the B12 recommended.

I read this article with great interest. I have Non-diabetic Peripheral Neuropathy and I was taking B12 for it. I took it for several years with no real relief. Then I read an article about the B12 vitamins that told of B12 Methylcobalamin instead of Cyanocobalamin. I am on 2000 mg daily. It has helped my nightly symptoms greatly. Recent blood work showed my B12 count as very high so we are hoping there will be no adverse reactions. I had to search various pharmacies and outlets and discovered it at Sam’s.

I too use the methylcobalamin which came in bottles of only 30 tablets from Vitamin World, meaning it was much more expensive than Sam’s bottles of 300 at $19.

However, being identical both are 5000 mcg. How do you get to 2000 mg? I think that would be 40 tablets a day. And if you meant to say 2000 mcg then that would equal 2/5 of a tablet per day. Can you give me some clarification please.

Why don’t we all read articles like this, and eat an appropriate diet of vegetables and fruit with little meat? Don’t depend on doctors to solve your problems. You need to care for yourself with the help of your doctor!

I am a nurse practitioner in an internal medicine office. If I could practice the way I wanted to I would order B12, vitamin D, and magnesium levels on every patient I see. Sadly, insurance will reject a majority of these tests. There are ICD-10 codes that are entered to show the reason why we are ordering a test. For example, vitamin D will get covered if there is a vitamin D deficiency, osteoporosis, or osteopenia. Vitamin B-12 is covered by B-12 deficiency, anemia or hair loss. Tingling (one of the main reasons we check B-12) will sometimes get covered. The obvious question is: how do we know if there is deficiency if we are unable to get a baseline test. The limitations are even more pronounced with Medicare patients. There are limits to how many times a year we can check these levels and that is if there is an ICD 10 code that justifies ordering the test. Nothing is worse than having a Medicare patient come in with a $600 bill from their laboratory because the test was not covered.

Many of the healthcare providers are just as frustrated as the patients are when it comes to having these tests conducted. I am a faithful listener of The People’s Pharmacy. I have weaned most of my patients off of PPIs. I have patients soaking raisins in gin, and we are talking about meditation instead of benzodiazepines.

Good job Amy; your patients are lucky to have you.

What do you do if you are allergic to all B vitamins?

I wonder if you really mean allergic to. I realized decades ago I could not tolerate a multi B vitamin because one or another of the Bs was a problem for me. So I have had to select which individual B I might need such as B 12.

I have been on a PPI drug for two years. I weaned off it and am now on Zantac. I am also on Prednisone for an auto immune illness. My doctors have not checked my B12 levels even though I have complained of extreme tiredness. I started taking a B12 caplet three weeks ago. I am beginning to get my energy back. I had numbness in my feet, and that has partially gone away. I am feeling more mentally alert and sleeping better.

I thought the same for many years. Then I discovered I have a MTHFR (gene variant) that prevents me from breaking down folic acid. Worse than that, it attaches to the receptors and blocks the body from using dietary B6 and 12 sources. Try taking a brand that has methylated forms of B6 and B12. More expensive, but worth it.

A little over 10 years ago, I’d been on Zyrtec every day for two years and began having balance problems. I discontinued the drug, and after about a week my balance began to improve very slowly. Around that same time, but seemingly unrelated, I had “buzzing” in my legs and a chronic burning sensation on my tongue. (I thought it was peri-menopausal.) After an EEG, MRI, and vestibular tests, my neurologist told me my B12 was 75, and she couldn’t believe I didn’t have nerve damage.

None of my doctors ever really believed me about the Zyrtec-balance correlation, but in years since I have that read drugs of that type can deplete B12 and that lack of B12 can cause balance problems. (I think Zyrtec can also be ototoxic.) Since I’m not much of a meat-eater, I began taking methyl B12 then, and still do. My levels stay around 800, and I have more energy at 60 than I had at 45. Oh, and no burning, buzzing or balance issues — in fact, I successfully paddle boarded on the first try this past weekend!

My husband (age 70) was just diagnosed with a B12 deficiency. Why is a B12 test not a part of regular blood work after a certain age? The symptoms mimic dementia, and myriad other illnesses, including depression, anxiety, and ambivalence. He’s gradually getting better, after a month on B12 supplements.

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