(Important note: STTM is an information-only site based on what many patients have reported in their treatment. Please work with your doctor. This is not meant to replace that relationship or guidance, and you agree to that by reading this website. See the Disclaimer.)

B12 is a vitamin which has a key role in red blood cell metabolism of your entire body, giving you energy, sharpness in your brain, and healthy nervous system functioning.

Why do I, as a thyroid patient, have a risk of low B12?

Unfortunately, a certain percentage of hypothyroid patients have low levels of this important vitamin. And that deficiency is largely due to years of low stomach acid levels due to our hypothyroidism, whether one is either undiagnosed due to the lousy TSH lab test or poorly ­treated on T4 meds. Celiac can also lead to low B12 due to the damage it causes. So can the use of the prescription medication Metformin for diabetes treatment.

Other reasons for low B12 include having the h. pylori bacteria, the autoimmune Pernicious anemia which attacks parietal cells and intrinsic factor, preventing the absorption of B12, and patients who are mis-prescribed Proton Pump inhibitors.

What are symptoms of low B12?

Symptoms can vary from person to person, and you can have some, but not all. Your symptoms can be different from someone else’s. Here are some reported by those with low B12:

• numbness/tingling/pins and needles in your hands, arms, legs or feet (Janie noticed it with her pinky fingers, or when she crossed her legs)

• leg pain

• difficulty walking with balance

• weakness in muscles

• tremors

• poor reflexes

• tongue soreness

• pale in complexion

• headaches

• feeling of dizziness

• vision problems (blurriness, spots in eyes, etc)

• breathlessness

• memory problems/forgetfulness (giving you a wrong diagnosis of dementia or Alzheimers!)

• irritability

• confusion or brain fog

• fatigue

• depression

• difficulty getting pregnant

What do I look for with B12 labwork?

Patient observation has repeatedly shown that just being “in range” is not key–we can still have a few key symptoms about inadequate B12. Instead, patients saw that putting their B12 lab result in the upper quarter of the range got rid of those few pesky, inadequate B12 symptoms they had.

How do I correct low levels of B12?

There are few important points to underscore here.  First, the vast majority with low levels have reported being able to raise their B12 levels with oral supplementation in pill, lozenge or liquid form. That amount is often reported as 5000 mcg. So if you are told that injections are the only way, not true. Or if your B12 results aren’t that bad (but need improvement), it’s also not true that you HAVE to have injections.

On the other hand. those who did choose injections (usually for those with pitifully low results) report quicker positive results. For those with the autoimmune-related pernicious anemia who have difficulty properly absorbing B12, injections are usually recommended in most countries, but again, oral has worked well if enough it used. Work with your doctor.

IMPORTANT: Do note that many of us NEED to have an acid in our drinks that we use to swallow an oral product, such as lemon juice or apple cider vinegar. An acidic environment is needed in our stomachs to break down and absorb. Also, sublingual B12 administration has outright given a positive experience with patients who have leaky gut.

Diet-wise, it’s recommended to increase your consumption of meat and dairy products, which can be rich in B12…if you tolerate them. It’s individual, tho.

I see different kinds of B12 in the store. Which one?

  1. The Methylcobalamin version is considered the most active and absorbable, thus the most recommended. It helps lower high homocysteine levels due to a genetic methyl blockage issue like MTHFR. But, some with the MTHFR mutation actively expressing itself may need the Hydroxy version just below.
  2. The Hydroxycobalamin version of B12 is not natural in your body, but it can convert well to a more useable form of B12 and can last longer in your body. It’s often used for injections. It helps if you’ve had cyanide poisoning from tobacco smoke exposure, as it will bind and remove it..i.e a good detoxer.  But note that certain experts state it’s better to use the methyl version.
  3. The Adenosylcobalamin version of B12 is a natural and active form and stated to be effective against cancer growth, plus being primarily used by the mitochondria. It occurs naturally in foods derived from animals (eggs, meat, dairy, etc). Those with MTHFR have also stated they like this one, as well.
  4. The Cyanocobalamin version of B12 is inactive and are the most common ones often seen on store vitamin shelves, but it’s the least absorbable, and still needs to be converted to a more usable version in your body (i.e. to the Methyl and Adeno versions above), which if you have a genetic methyl blockage like MTHFR, wouldn’t be your best B12 supplement.

How long do I need to be off B12 supplements before testing again?

It’s honestly all over the map. There are some lab test pages or doctors that say you don’t have to stop before doing labs, or at least be off 12 hours minimum Other places, you might see 2-3 weeks, and up to 4 weeks. Perhaps the bottom line is take heed if someone tells you to be off for several months–not good.

What’s the connection between B12 and B9 (Folate)?

Both B12 and B9 (folate) are needed for good red cell production, and deficiencies in either can cause similar symptoms. So it’s common to see lab testing combine the two. When pregnant, the old school of recommendation was to supplement with “folic acid” to reduce the risk of miscarriages. But folate is the natural version of folic acid and is more desirable, especially if you have the MTHFR gene mutation. 

What prescription meds or OTC supplements can inadvertently lower B12?

Stomach acid reducers like Prilosec, as well as lansoprazole, pantoprazole, omeprazole, esomeprazole and raberprazole and others, put you at a higher risk of lowering your B12 levels. In fact, too many of us have been put on those stomach acid reducers, when in reality, most of us make too LITTLE stomach acid and which causes acid reflux and the false appearance of too much.

Pernicious anemia–can you explain more about this B12 condition?

Pernicious Anemia (PA) is an autoimmune condition, meaning the body’s antibodies are attacking its own bodily tissue. In this case, one’s antibodies are attacking what’s called Intrinsic Factor — a glycoprotein produced by parietal cells in the stomach lining. This glycoprotein plays a role in extracting B12 from food. So if that protein is being attacked, B12 is not being absorbed.

Less common but still valid causes of PA include different stomach issues, such like stomach surgery, gastric ulcers or tumors, and even excess alcohol consumption1. One research study found that 50% of those with the autoimmune Hashimoto’s disease have Pernicious Anemia2.

How to treat Pernicious anemia? Some countries lean towards injections, but there are plenty of PA patients who found that oral B12 in high enough amounts worked fine for them. Do work with your doctor.

What if I have high B12?  

One cause can be liver stress due to your hypothyroid state, meaning it won’t be doing a good job clearing out your excess B12. Or any other stresses can do this!

Another very common cause can be the genetic defect in your MTHFR gene. If you have a family history of heart disease, heart attacks, cancers, breast cancers, or strokes, etc, or if hair testing has revealed high heavy metals, time to look very closely at your MTHFR gene, especially 1298 and 677. See link above. Note that some patients report that if their high B12 is due to the MTHFR gene mutation, they have symptoms of low B12, meaning that B12 is not being broken down for use, i.e. a “functional deficit in B12”, even with a high blood level.


The following stories reveal that low B12 can have some fairly powerful symptoms–some which can mimic low thyroid or an adrenal problem!

Marilyn’s Story: I had a B12 level of 189 five years ago. In the beginning, I tried the mega-doses of B12, but they did nothing for me, and I had to take the monthly shots. My thyroid specialist recommended B12 Dots (found in health food stores or organic sections of stores). Put under your tongue, they are absorbed into the blood stream directly. One a day and I am back to normal. No more shots and no more big pills to take. I use the 500 mcg dot, but I know they also make a 5000 mcg dot.

Jennifer’s Story:  When I figured out I was low on B-12 (not by having it tested—it was at normal levels) and started B-12 injections via my doctor’s recommendation,  I was stunned to discover how many of my symptoms  that I thought were due to wrong levels of thyroid meds or HC,  were due to B-12. Of course the B-12 deficiency came about due to hypothyroidism causing slowed digestive system, low stomach acid, poor absorption of B-12…so I guess you could say it was a thyroid set of symptoms,  yet I “fixed” them, for now, with B-12.

The B-12 relieved free-floating anxiety, quite a bit of the brain fog–the part where my brain just kept “slipping” and going off-line, some of the lack of energy, and some of the difficulty sleeping. ALL of the free-floating anxiety though, which I did not expect at all–I was sure that must be from the adrenals or thyroid stuff. I’ll probably never know if the tingling/numbness in my hands, feet and face were caused by this. Apparently it’s common and it can be permanent. There are so many possible causes of that particular symptom that I just don’t know.

What I learned from reading the book with the annoying title: “Could it Be B-12?” is that neurological symptoms show first and before there’s any indication in the blood work. The title’s annoying because when you see it lying around all the time you start talking to yourself and answering the question and posing the question to yourself and everyone else around you. If you get this book be sure to cover it or turn it face down when you leave it or you’re going to hear people asking the question.

At first I did ten days in a row of injections and was ready to be the B-12 poster girl. Then I tried to go to every other day and my brain started slipping immediately and little fingers of anxiety started poking at me again. I went back to every day for awhile, switched from cyanocobalamin to methylcobalamin (supposed to be more easily absorbed and stay in the system longer) and now I’m down to 2X/week without losing gains.

Interesting, eh? The B-12 test I had was the one they use to catch early and mild cases. Nothing.

Meleese’s story: My levels were consistently in the 200-240 range and I had 2 doctors emphatically refuse me injections. I got to the stage where I could barely function, so I saw a “good doc” (listed in the NTH files) when she opened her books to new patients (she only opens them a couple of times a year).  She was horrified and taught me to self inject. We can buy hydroxo OTC here in Australia, so at the moment I am injecting about every 3 days. Improvements already are….better sleep, muscle pain has lessened (it was horrendous I could barely use my arms) I can feel my feet again, especially my toes. My balance is improving (although I still use a walking stick). My energy levels/ brain fog are slowly improving. I still can’t read (one of my great loves) but am getting there.

Have you a story to tell of low B12 and successful treatment that could help others? Use the Contact Me for sending your story, and I’ll put it right here. Please keep it short.

More reading:

Vitamin B12: All Cobalamins are not Equal

Four Forms of B12 -Which One is Best?

** Where can I read more about this?  I highly recommend the book Could It Be B12? An Epidemic of Misdiagnoses by Sally Pacholok, R.N. and Jeffrey Stuart, D.O.

** HAVE YOU LIKED THE STTM FACEBOOK PAGE?? Daily information or inspiration!

** HAVE YOU GOTTEN THE TWO STTM BOOKS?? GREAT INFORMATION FOR REFERENCE and to take right into your doctor’s office. 

  1. https://en.wikipedia.org/wiki/Intrinsic_factor
  2. https://www.ncbi.nlm.nih.gov/pubmed/24424200