Eating a well-balanced diet is important for your health. Having an imbalance in certain vitamins and minerals can cause problems with normal functioning. One part of the human body affected by nutrition is the nerves. Your nerves in the peripheral nervous system relay information between the brain and spinal cord and the rest of your body. For example, the sensory nerves carry sensations from the body, such as from the hand to the brain. The motor nerves carry information from the brain to the muscles, such as to move your hand away from a hot object. Another group of nerves in the peripheral nervous system is the autonomic nerves, which relays signals to the glands and organs. Damage to these nerves can result in a variety of symptoms. Damage to the sensory nerves can result in numbness, burning sensations, nerve pain and tingling. Motor nerve damage symptoms include problems swallowing, muscle cramping, lack of muscle control and muscle atrophy. Damage to the autonomic nerves can cause abdominal bloating, urinary incontinence, diarrhea and blurred vision. These nerves can become damaged due to abnormal vitamin levels: either too little or too much of a vitamin.
Vitamin B-12 occurs in several foods, such as fish, red meat and eggs. But not everyone gets enough vitamin B-12 in their diet, leading to a deficiency. The Linus Pauling Institute noted that strict vegetarians and vegans can suffer from a vitamin B-12 deficiency, since the vitamin occurs in animal products. A deficiency can occur as a result of a malabsorption syndrome or pernicious anemia. The University of Chicago added that a vitamin B-12 deficiency is common in the elderly, with an estimated 10 to 25 percent of people over the age of 80 having the deficiency. A vitamin B-12 deficiency damages the myelin sheath, which is the covering around the nerves, resulting in abnormal nerve functioning.
Having a deficiency in vitamin B-1, or thiamine, can also result in nerve damage. Too little vitamin B-1 in the body can lead to a condition called beriberi. Two main types of beriberi exist: dry beriberi and wet beriberi. Dry beriberi affects the nervous system, while wet beriberi affects the cardiovascular system. MedlinePlus noted that while beriberi is a rare condition in the United States, it can affect alcoholics. Alcoholism interferes in the body's ability to absorb vitamin B-1, leading to a deficiency. If left untreated, a vitamin B-1 deficiency can result in Wernicke-Korsakoff syndrome, a neurological condition that affects muscle coordination and vision, and later memories.
While abnormally low levels of certain vitamin can cause nerve damage, so can abnormally high levels of other vitamins. One such vitamin is vitamin B-6, which is found in fortified cereals, spinach, salmon and bananas. The danger of nerve damage from vitamin B-6 comes from taking too much of the vitamin supplement. The Linus Pauling Institute noted that cases of sensory nerve damage have occurred in people taking more than 1,000 mg of vitamin B-6 supplements a day; the site added that there have also been reported cases of sensory nerve damage in people who took less that 500 mg a day of vitamin B-6 over several months. The tolerable upper intake level of vitamin B-6 is 100 mg a day. Talk to your doctor before taking supplements over the tolerable upper intake level.