You’ve been getting numbness and tingling into your hands, legs, or feet. You’ve been to physiotherapists, chiropractors, massage therapists, neurologists, and acupuncturists. Nothing is helping. Could the cause of your numbness and tingling be a vitamin B12 deficiency even though you have been told by your MD your lab results are normal?
Vitamin B12 and your nerves
Your brain and nerves send electrical signals to all of your body parts so they work properly. For those signals to work properly, your nerves need to be protected or insulated by what is called a myelin sheath. Myelin would be similar to the sheath or plastic on the electrical wires in your house.
Vitamin B12 is a vital component in the formation and maintenance of your myelin sheath. Being deficient in Vitamin B12 can cause damage to your myelin sheath which will disrupt nerve signals to and from your brain. One of the common symptoms because of myelin damage related to vitamin B12 deficiency is numbness and tingling in the hands and feet.
One of the common symptoms because of myelin damage related to vitamin B12 deficiency is numbness and tingling in the hands and feet.
Other symptoms of vitamin B12 deficiency
Beside numbness and tingling in your hands or feet you may experience the following (1):
- “brain fog” or difficulty with thinking and memory loss
- fatigue
- weakness
- problems with walking, coordination, or balance
- swollen, inflamed tongue
- yellow skin (jaundice)
- paranoia or hallucinations
How do you know if you are deficient in vitamin B12?
Unfortunately, at the time of this writing, vitamin B12 isn’t checked routinely by your medical doctor. If it is checked, it will be done by measuring your levels in the blood. However, the lab ranges conventional medicine uses to measure vitamin B12 are low. Because of these two issues, vitamin B12 deficiency is often under-diagnosed.
A quick note about lab ranges: conventional lab ranges are designed to detect clinical disease, whereas functional lab ranges are designed to promote optimal health or catch a health problem before it is too late to fix. So you want your lab markers to be in the functional range.
If vitamin B12 is found to be low in the blood that is considered to be the final stage of B12 deficiency. By the time the last stage rolls around, signs and symptoms of vitamin B12 deficiency become more obvious. Numbness and tingling (peripheral neuropathy) or brain fog do not appear until the final stage. This is very important because by the time symptoms like this appear it may be too late to reverse them.
Numbness and tingling (peripheral neuropathy) or brain fog do not appear until the final stage of vitamin B12 deficiency. This is very important because by the time symptoms like this appear it may be too late to reverse them.
It’s important to make sure your vitamins B12 levels are in a higher range and that the following markers are checked if they are available where you are living:
Stage 1 and 2 deficiency
A lab marker called HoloTC (holotranscobalamin-2) will be reduced. Even though this marker is considered to be the most sensitive marker for B12 deficiency, at the time of this writing, it is not readily available.
Stage 3 deficiency
A lab marker in the blood called homocysteine will be high. Homocysteine can also be high with folate deficiency so folate should also be measured to rule that out. These are widely available markers.
Homocysteine
Conventional range: 0–15 µmol/L
Functional range: < 7 µmol/L
Folate
Conventional range: >10 nmol/L (> 3 μg/L)
Functional range: >18.1 nmol/L (> 8 μg/L)
A lab marker in the blood or urine called MMA (methylmalonic acid) will be high. Measurements in urine would be more sensitive if you do not have kidney problems. This marker isn’t readily available where I am from, but is available through a private lab.
MMA (methylmalonic acid)
BLOOD/SERUM
Conventional range: 0–378 nmol/L
Functional range: < 300 nmol/L
URINE
<2.2 ug/mg
Stage 4 deficiency
Where I am from (Edmonton, Alberta, Canada) the conventional lab range is 120-150 pmol/L (163-203 pg/mL). People can experience the effects of vitamin B12 deficiency in a range of 156-258 pmol/L (211-350 pg/mL). (2) As mentioned, the conventional lab ranges are designed to detect disease rather than detecting a problem before it turns into a disease. There is the possibility you have been told your B12 is normal. Yet, you’re not feeling well and have signs and symptoms of vitamin B12 deficiency.
Again, you want to make your B12 levels in your blood (serum) are in a higher range. The functional range you want to be in for serum B12 is 332-1476 pmol/L (450-2000 pg/mL).
You want to make your B12 levels in your blood (serum) are in a higher range. The functional range you want to be in for serum B12 is 332-1476 pmol/L (450-2000 pg/mL)
As well, once you get to stage 4 deficiency you can get macrocytic anemia. So you will see other markers such as a low red blood cell count, low hemoglobin, low hematocrit, and elevated MCV, MCHC, MCH, and RDW.
Reference for stages of Vitamin B12 deficiency (3)
Summary
Numbness and tingling in the hands, legs, or feet is a common symptom. Vitamin B12 deficiency is one of the main causes of numbness and tingling. Vitamin B12 is vital for your brain and nerves to function properly. Make sure you get your B12 blood levels checked and other markers if possible. The earlier you detect if you have vitamin B12 deficiency the easier it is to fix.
In future articles, I will discuss other important functions of vitamin B12, causes of vitamin B12 deficiency, and treatments to get your levels optimized. (causes and treatments)
I had borderline vitamin B12 levels on last bloods. I have had persistent pins and needles in both arms for over a year. I’ve been taking B12 supplements as well as Amitrypyilline 10mg and naproxen for pain. Symptoms have improved a little but I now have scalp tingling and pins and needles in the left side of my head.
Hi I also am on that medication and have had tingling and pins and needles for over a gear.
My iron levels fluctuate but generally low.
I eat very little meat due to my husband’s obsession with vegetarianism.
Hi! I had similar issue, but my cheeks and both hands would get pins and needles and I would feel short of breath. Even though I was on b12 vitamins. This is because I was vegeterarian. I was suffering so much I just started eating meat again and it went away. Now I only get pins and needles when I’m about to get diarrhea since the body doesn’t absorb vitamins well when you have diarrhea. But yeah never going back to being vegetarian, my body can’t handle it
I was extremely low
,at 120, for b12 and iron. Was taking supplements now they are saying bloodwork is normal but i still feel slight buzzing sensation sometimes in legs and am experiencing vertigo like symptoms. Any insights?
Hi Liliana,
Sorry without a proper history and exam it’s hard to say. A lot of numbness and tingling can be caused by a structural problem in the spine pinching the nerves. Vertigo can also be caused by structural problems in the neck area of the spine. You might want to visit a chiropractor to get a thorough health history and assessment done to see if that’s what’s causing your residual problems.
Dr. Collins
I have tingling in my right hand due to a pinched nerve in my neck from a car accident years ago. I have been seeing a chiropractor for this but now I have tingling in my legs, back and torso. Can B12 deficiency cause numbness in the back and torso as well as the legs, hands and feet?
Hi Vienna,
Tingling because of vitamin B deficiency would most commonly occur in the hand, legs, and feet. I have seen torso tingling and numbness (more rarely) due to “pinched” nerves in the back as well as shingles. However, proper lab work would determine if B12 deficiency is an issue for you.
Dr. Collins
I started treating my b12 deficiency two months ago. I was experiencing amazing results within the first month. After a month my doctor ordered a blood test to check my levels. They were back to normal. However, immediately after I stopped taking injections my symptoms were back. Should I continue to get injections?
Hi Claudia,
B12 injections are beyond my scope of practice and area of expertise. As well, without me being one your primary care providers and knowing your complete history and exam results, I would not be able to give you an answer to your question. In your situation, it sounds like you might want to get your b12 levels checked again to verify if you are deficient again.
Dr. Collins
I have had a numb hand for a year, and now a numb foot, the brain fog is AWFUL -and that’s been there for a year. Please please can someone tell me what specialist I can see about this? My GP just says my levels are normal. They don’t understand that you can have a normal reading and be seriously deficient. Please can someone help me with this. I’m in England.
Hi Rowan, search for either a functional medicine practitioner or a naturopath in your area to see if they can help you.
I’ve had numbness and tingling in the ball of feet and toes for over 5 years now. I’ve just recently been formally diagnosed with Vitamin B12 deficiency and put in 1000 iu of b12 sublingual. My level was at 102 last time checked on Feb 29 by BC Health. Upon going back over my previous blood work I see it was checked on December at 118 and last May at 201. Why was this deficiency not caught!? I told drs about tingling in toes but wasn’t until I presented with other symptoms such as brain fog, high LDL and rapid weight loss that the doctors decided my B12 levels were low.
Sorry to hear about this Cheryl. Unfortunately, our current healthcare system is more reactive versus proactive. Hopefully you can turn your levels around and start to feel better.