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7 Warning Signs of Vitamin B12 Deficiency

By dsorbello at Jan. 18, 2019, midnight, 60406 hits

By Ethan Andrews
September 29, 2014 at 10:57am EDT

The importance of B12 in the human body is hard to overestimate.

And while you hear things like how it’s important for your nerves, DNA and red blood cells among many other things, what does a lack of it actually do in more “every day” language?

To answer that, let’s take a look at a case study of what can happen when your levels get too low.

A real life example of what happens from low B12

The New England Journal of Medicine reported on the case of 62 year old man who, during the course of several weeks, starting having varied symptoms.

He experienced numbness, difficulty walking and intense joint pain. He had “stinging” sensations in his hands almost like pins poking him. His skin took on a yellowish color and shortness of breath would often occur.

He was checked out at Massachusetts General Hospital and they pinpointed the cause as a severe lack of B12 in his blood.

I highly encourage you to get a blood test for B12 and to know what your own levels are.

If you can’t do that anytime soon, here are 7 common warning signs that are linked to low levels of this vitamin.

Signs that you may be B12 deficient

Memory loss, impaired thinking and general cognitive difficulties.

If you have difficulty walking, tend to stagger, or have balance problems.

Various and “odd” sensations throughout your body, numbness, or tingling that occurs in your hands, legs or feet

Yellowish or jaundiced skin.


A swollen tongue or if it’s inflamed.

General weakness and fatigue

If B12 levels drop to into the severely deficient range, it can lead to much worse conditions.

Deep states of depression, hallucinations and paranoia are all associated with extremely low levels. Losing the ability to taste and smell has even been linked to low B12.

And since it’s such an important part of brain health, it can lead to greatly diminished brain functioning, beyond what is mentioned above.

So what leads to low B12?

Here are some things to look out for, that can lead to or cause lower B12 levels.

A vegetarian or vegan diet (since plants don’t make B12, and you would need to supplement with B12 to keep your levels up).

Certain medications like PPI’s

Gut issues such as “leaky gut” or an inflamed gut.

Pernicious anemia

Low stomach acid or taking drugs to suppress acid production in the stomach.

Other things can include Metformin, a drug used for diabetes, people aged 60 and over and women who have had infertility issues in the past.

What to do?

Eat a lot eggs, dairy, poultry and animal sources of protein, which are all good sources of this vitamin.

(Quick note: you may hear things like fermented soy or spirulina and other sources have B12, but many of these plant-based foods have B12 analogs. These are called cobamides and they can block your intake of “real” B12 that your body needs).

If eating any of the above isn’t an option for you for any reason, you’ll want to supplement with B12.

And a form of B12 called methylcobalamin is your best bet, since it is better absorbed within your body.

OK, so what are optimal B12 levels to shoot for?

In the United States, you’ll see lab reference ranges as low as 250 or 300 pg/mL (picograms per milliliter) listed as “normal” when they are anything but.

As an example, Japan uses a lower limit of around 500 pg/mL and recommends treatment for anything below that number since B12 deficiency symptoms can start showing up at levels lower than 500.

Personally, I’d like to see B12 levels in the 800 to 1200 pg/mL range for optimal health.

Please do get your levels tested though as soon as you can.

And if you happen to find yourself with any of the warning signs described above or with levels of 400 or lower, you may want to boost your B12 and see what this powerful vitamin can do for you.

Posts [ 3 ] | Last post Jan. 18, 2019, midnight
#1 - Oct. 13, 2014, 11:06 p.m.
Daniel Peng

Thank you for sharing this. It's really helpful.

#2 - Oct. 14, 2014, 4:30 p.m.


Thank you for sharing this. It's really helpful.

i thank you also

#3 - Feb. 27, 2015, 1:44 a.m.

You can usually get all your vitamins from the foods you eat. Your body can also make vitamins D and K. lack of vitamin B12 we leads to many complixation from digestion to blood circulation and cells growth. As vitamin B12 paridoxic and folic acid place important role in RBC formation and cell progression or new cell formation. You can purchase or buy vitamin B12 from trusted pharmacy.