6 Signs You Might Have a B12 Deficiency

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via Observer

A deficiency of vitamin B12 can sneak up more easily than we think. With more than three million people developing it in the United States, it’s considered a common nutritional deficiency.

The human body requires vitamin B12 for many important functions. It’s needed to make red blood cells, nerves, DNA, and to convert our food into fuel. Additionally, vitamin B12 protects our blood cells in order to prevent megaloblastic anemia, a condition that reduces the amount of oxygen that red blood cells can carry throughout the body.

The recommended dietary allowance for B12 is 2.4 micrograms each day. Generally, most people are able to meet this requirement from their dietary choices.

There are numerous reasons why a person may develop a vitamin B12 deficiency. However, unless you know what the signs of what a deficiency of this vitamin looks like, you could be left in the dark, risking serious issues to your health. Here are six signs that you might have a vitamin B12 deficiency:

Feeling exhausted

Are you experiencing excessive tiredness, weakness or shortness of breath? It could be traced back to a B12 deficiency. Megaloblastic anemia can develop if insufficient B12 is available. Without it the body will produce large, immature red blood cells that are unable to transport oxygen throughout the body. When cells don’t receive the oxygen they need, you will feel more tired than usual.

Medications for heartburn

People experiencing the uncomfortable burning feeling from heartburn will often medicate themselves with a prescription medication to reduce stomach acid brining relief. The problem, though, is that vitamin B12 requires stomach acid to be absorbed. Here’s why: In our food, vitamin B12 is attached to a protein that must be removed in the stomach by gastric acid and an enzyme called pepsin. Once it is, a binding protein attaches to it, protecting it until it reaches the small intestine. In the small intestine, a substance called intrinsic factor takes B12 from the binding protein where it is absorbed into the bloodstream.

Tingling and numbness in hands and feet

Vitamin B12 makes myelin, the protective covering for nerves. If our nerves aren’t covered, they are exposed to possible damage, including shrinkage of the nerves. This shrinkage can cause a pins and needles sensation in addition to numbness. If you are experiencing this, see your doctor for a correct diagnosis.

Pale or yellowish skin

Having a vitamin deficiency can reveal itself in how your skin color appears. This is because red blood cells are unable to carry necessary oxygen, bringing a pale pallor to the skin.

A yellow hue can be due to jaundice, which can be a symptom of a severe lack of vitamin B12. However, don’t assume that’s the cause; other conditions, such as liver cancer, can bring about this color as well. Always go to a doctor to investigate the cause.


Vitamin B12 improves neurotransmitter production, such as serotonin, that keep our brain functioning properly. If serotonin has become deficient, depression can ensue. Insufficient B12 can result in reduced communication between nerves.


Memory loss and even symptoms of dementia can be brought about by a B12 deficiency. This can particularly affect the elderly, since vitamin B12 works with metabolic processes in the brain. As we age, we make less intrinsic factor, the compound needed to absorb vitamin B12.

If an elderly person is showing signs of memory loss and forgetfulness, have their vitamin B12 status checked to rule out a deficiency that could be causing this problem.

People at risk of developing a deficiency:


Vitamin B12 is only found in foods of animal origin—no plant-based foods contain it. Food sources of B12 include meat, eggs, poultry, fish, eggs and milk products. Therefore, strict vegans place themselves at risk of a B12 deficiency.

Vegans need to make sure they are taking a B12 supplement and consuming foods fortified with B12, such as some breakfast cereals, soymilk and nutritional yeasts. Check the nutrition facts label to investigate if food contains vitamin B12.

People over the age of 50

With increased age, less stomach acid is produced by the body. Since stomach acid is necessary for vitamin B12 absorption, people over 50 are more at risk of becoming B12 deficient. If you are over 50, you should discuss with your doctor if you should take a supplement.


A 2016 study showed that out of 283 type 2 diabetics prescribed a high dose of the diabetic medication Metformin, 33 percent had a vitamin B12 deficiency. Another study found that those with type 1 diabetes are also at risk; out of 90 individuals with type 1 diabetes, 45 percent had deficiencies of vitamin B12.

Dr. Samadi is a board-certified urologic oncologist trained in open and traditional and laparoscopic surgery and is an expert in robotic prostate surgery. He is chairman of urology, chief of robotic surgery at Lenox Hill Hospital. He is a medical correspondent for the Fox News Channel’s Medical A-Team. Follow Dr. Samadi on Twitter, Instagram, Pintrest, SamadiMD.com and Facebook.

6 Signs You Might Have a B12 Deficiency
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Dr. David Samadi, MD.

Dr. David Samadi is a Urologic Oncology Expert and Robotic Surgeon who was included in the prestigious Castle Connoly's America’s Top Doctors and New York Magazine’s Best Doctor’s List.

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Dr. David Samadi, MD.

Dr. David Samadi is a Urologic Oncology Expert and Robotic Surgeon who was included in the prestigious Castle Connoly's America’s Top Doctors and New York Magazine’s Best Doctor’s List.