8 Signs and Symptoms of Vitamin B12 Deficiency

Vitamin B12, also known as cobalamin, is one of the most important water-soluble vitamins. Apart from producing red blood cells and DNA, it also plays an important role in the proper functioning of your nervous system. Vitamin B12 is found naturally in animal foods, including meat, fish, poultry, eggs, and dairy products. However, it can also be found in B12-fortified products, such as some types of bread and plant-based milk.

Unfortunately, B12 deficiency becomes more common, especially as we age. If you’re not getting enough from your diet or absorbing enough from the foods you eat, you’re at risk for a deficiency.

People at risk for B12 deficiency include:

The elderly
Those who’ve had surgery that removes the part of the bowel that absorbs B12
People on the drug metformin for diabetes
People following a strict vegan diet
Those taking long-term antacid drugs for heartburn

Unfortunately, symptoms of a vitamin B12 deficiency can take years to appear and diagnosing it can be complicated. B12 deficiency can sometimes be confused with folate deficiency. Low B12 levels cause your folate levels to drop as well. If you have a B12 deficiency, trying to raise low folate levels may be the wrong treatment, while it won’t solve the underlying problem.

8 signs and symptoms of vitamin B12 deficiency:

1. Pale or Jaundiced Skin

People with B12 deficiency often appear pale or have a slight yellow tint to the skin and whites of the eyes, also known as jaundice. This happens when a B12 deficiency causes problems with your body’s red blood cell production. Vitamin B12 plays an important role in the production of the DNA needed to make red blood cells. Without B12, the instructions for creating cells are incomplete and cells cannot divide. This condition causes a type of anemia called megaloblastic anemia, in which the red blood cells produced in your bone marrow are large and fragile.

These red blood cells are too large to pass from your bone marrow into the circulation. Because of this, you don’t have many red blood cells circulating in your body and your skin may look pale. The fragility of these cells means that many of them break down, causing excess bilirubin. Bilirubin is a slightly red or brown colored substance produced by the liver when it breaks down old blood cells. Large amounts of bilirubin are what give your skin and eyes a yellow color.

2. Weakness and Fatigue

Weakness and fatigue are common symptoms of vitamin B12 deficiency. They occur because your body doesn’t have enough vitamin B12 to make red blood cells that carry oxygen throughout your body. It cannot efficiently transport oxygen to your body’s cells, causing you to feel tired and weak.

In the elderly, this type of anemia is often caused by an autoimmune condition known as pernicious anemia. People with pernicious anemia do not produce enough of an important protein called intrinsic factor. Intrinsic factor is needed to prevent B12 deficiency because it binds to vitamin B12 in your gut so you can absorb it.

3. Needle and Needle Feelings

One of the more serious side effects of long-term B12 deficiency is nerve damage. This can occur over time, as vitamin B12 is a major contributor to the metabolic pathway that produces the fatty substance myelin. Myelin surrounds your nerves as a form of protection and insulation. Without B12, myelin is produced differently and your nervous system cannot function properly. A common sign of this is paresthesia, or a pins and needle-like sensation in your hands and feet.

Interestingly, the neurological symptoms associated with B12 deficiency often co-occur with anemia. However, one study found that about 28% of people have neurological symptoms of B12 deficiency without any signs of anemia.

4. Mobility Changes

If left untreated, damage to your nervous system caused by B12 deficiency can cause changes in the way you walk and move. It can affect your balance and coordination, making you more prone to falls. This symptom is usually seen with undiagnosed B12 deficiency in the elderly because people over 60 are more prone to B12 deficiency. However, preventing or treating deficiencies in this group may improve mobility. Also, this symptom may be present in young people who have a severe, untreated deficiency.

5. Glossitis and Mouth Ulcers

Glossitis is the term used for inflammation of the tongue. If glossitis is present, the tongue changes color and shape and becomes painful, red, and swollen. Inflammation can also cause the tongue to appear smooth, as all the small bumps on the tongue that contain the taste buds grow and disappear. In addition to being painful, glossitis can also change the way you eat and talk.

Studies have shown that a swollen and inflamed tongue with long flat lesions on it can be an early sign of vitamin B12 deficiency. In addition, some people with B12 deficiency may experience other oral symptoms such as mouth ulcers, a pins-and-needles sensation in the tongue, or a burning and itching sensation in the mouth.

6. Shortness of Breath and Dizziness

If you become anemic due to a B12 deficiency, you may feel short of breath and a little dizzy, especially with exertion. This is because your body lacks the red blood cells that your body needs to get enough oxygen to its cells.

7. Impaired Vision

A symptom of vitamin B12 deficiency is blurred or impaired vision. This can happen when an untreated B12 deficiency causes nervous system damage to the optic nerve that goes to your eyes. The damage can impair your vision by disrupting the nerve signal from your eye to your brain. This condition is known as optic neuropathy. Although worrisome, it is usually reversible with B12 supplementation.

8. Changes in Mood

People with B12 deficiency often experience sudden changes in mood. In fact, low B12 levels are linked to mood and brain disorders such as depression and dementia.

The “homocysteine hypothesis of depression” has been suggested as a potential explanation for this link. This theory suggests that high homocysteine levels caused by low B12 levels can damage brain tissue and interfere with signals to and from your brain, leading to mood changes. Some research suggests that vitamin supplementation may reverse symptoms in some people with B12 deficiency.

It’s important to remember that mood swings and conditions like dementia and depression can have a variety of causes. Therefore, the effects of supplementation in these conditions remain unclear.