B-12 & Neuropathy

With peripheral neuropathy, you have damage to the nerves in your peripheral nervous system, which send information back and forth to your brain and spinal cord. Three types of nerves can become affected with peripheral neuropathy: the sensory nerves, the motor nerves and the autonomic nerves, which control your organs. Peripheral neuropathy can result from different medical conditions, such as an HIV infection or diabetes, but a deficit in vitamin B-12 can also cause the nerve damage.

Causes

Around one-third of neuropathy patients have the condition due to a vitamin B-12 deficiency, according to the University of Maryland Medical Center. The way a vitamin B-12 deficiency damages your nerves is not understood completely, though a deficit in the vitamin can damage the myelin sheath, which covers the nerves, notes the Linus Pauling Institute at Oregon State University. Several factors may cause a vitamin B-12 deficiency, which may lead to neuropathy. For example, if you do not have enough vitamin B-12 in your diet, which can happen with a vegan diet, you can develop a deficiency. Conditions that interfere in your body's absorption of the vitamin, such as celiac disease, may also cause a vitamin-B12 deficiency.

Symptoms

Neuropathy that results from a vitamin B-12 deficiency can affect your movement. For example, you may have problems with coordination and weakness. Muscle control problems and trouble moving may result in falling. If the neuropathy affects your sensory nerves, you may have tingling in your feet or hands, pain or numbness, notes the University of Chicago. Neuropathy that involves your autonomic nerves can result in problems with urination.

Diagnosis

Diagnosing neuropathy due to a vitamin B-12 deficiency involves two steps: testing for levels of vitamin B-12 and assessing the damage to your nerves. The University of Michigan Health System notes that a normal vitamin B-12 level in the blood ranges from 160 to 950 pg/mL. When preparing for the vitamin B-12 test, do not consume anything other than water for 10 to 12 hours before getting the test. Your doctor will draw a sample of blood and send it to a lab for testing. To gauge the level of nerve damage, your doctor will perform a physical examination and will look for any problems in your reflexes. She may also perform an electromyography, a test of your muscle's electrical activity, and a nerve conduction velocity test, which looks at how fast that electrical activity moves.

Treatment

The University of Maryland Medical Center notes that using vitamin B-12 to treat deficiency-related neuropathy is a successful treatment option. Your doctor may recommend oral supplements of vitamin B-12 or injections of the vitamin. Another option is getting vitamin B-12 in your diet. Foods that contain the vitamin include milk, eggs, shellfish and meat. If the neuropathy symptoms are severe, you may need to make lifestyle changes to prevent injury. For example, MedlinePlus recommends installing railings if you have movements problems or using protective shoes if you have sensation problems.

Prevention

Getting an adequate amount of vitamin B-12 in your diet may prevent neuropathy due to a vitamin deficiency. If you are age 14 or older, MedlinePlus recommends 2.4 mcg a day of vitamin B-12. If you are pregnant or breast feeding, talk to your doctor about how much vitamin B-12 you should have in your diet or if you need supplements.