Vitamin and Nutrition Deficiency


Peripheral neuropathy may occur as a result of malnutrition, for which there are many causes including poor nutrition caused by an unbalanced diet and/or alcoholism. Additionally, a clear link has been established between a lack of vitamin B12 and peripheral neuropathy.

Vitamin B12 Deficiency Neuropathy

Vitamin B12 is an essential dietary nutrient—a B12 deficiency can lead to a number of serious conditions including peripheral neuropathy.

Vitamin B12 deficiency is common in the United States, especially among the elderly. It is estimated that between 10% and 25% of the people over 80 years of age may have a B12 deficiency. There are several causes of vitamin B12 deficiency. A strict vegetarian diet may promote a B12 deficiency because animal-based foods such as red meat, dairy products, fish, poultry and eggs are the only recognized source of dietary B12. A lack of B12, or the inability of stomach acids to aid in the absorption, also causes this deficiency. Consequently, drugs that reduce stomach acid should not be taken with B12 supplements. A number of other conditions, procedures, and drugs are associated with a reduced the ability to absorb B12. These include autoimmune diseases, pernicious or unexplained anemia, pancreatic diseases, ileal resection, Crohn’s disease, HIV infection, gastritis, gastric or small intestine surgeries, malabsorption syndromes, multiple sclerosis, and use of histamine2 receptor antagonists or proton pump inhibitors.

More recently, the chronic use of nitrous oxygen, also known as laughing gas, has been related to severe cases of B12 deficiency.

Symptoms of lack of vitamin B12 can cause serious anemia, nerve damage and degeneration of the spinal cord. It is common for anemia to develop first, but this is not always the case, especially if a person is taking a folate supplement. A lack of B12 damages the myelin sheath that surrounds and protect nerves. Without this protection, nerves cease to function properly and conditions such as peripheral neuropathy occur. Even B12 deficiency that is relatively mild may affect the nervous system and the proper functioning of the brain. Several types of neurological manifestations are described: progressive degeneration of spinal cord, optic nerve neuropathy, cognitive disorders and polyneuropathy. The nerve damage caused by a lack of B12 may become permanently debilitating, if the underlying condition is not treated.

Symptoms & Signs

(Not all symptoms and signs may be present.) Side effects of the lack of vitamin b12 may include:

  • Lack of coordination
  • Pain, numbness, and tingling in hands or feet
  • Imbalance
  • Sensory loss
  • Weakness

Evaluation & Tests for B12 Deficiency

(Not all evaluations and tests for B12 deficiency may be necessary.)

There are diagnostic tests to screen for vitamin B12 deficiency, to uncover the cause of B12 deficiency and to monitor the effectiveness of treatment.

Test to assess nerve damage include:

Treatment & Therapy

(Not all treatments and therapies may be indicated.)

  • Increase B12 in diet with:
    • Red meat
    • Poultry and eggs
    • Dairy products
    • Fish
    • Vitamin B12 supplements
  • Oral therapy of B12
  • Intramuscular injections of B12 are usually necessary
  • Take safety measures to compensate for loss of sensation
  • Early diagnosis and treatment may restore nerve damage

Did You Know?

Peripheral Neuropathy affects an estimated 30 million Americans and countless more worldwide.

The Foundation for Peripheral Neuropathy is a non-profit organization whose mission is to improve the lives of people living with peripheral neuropathy.