Your nervous system is involved in everything your body does, from regulating your breathing to controlling your muscles and sensing heat and cold.

There are three types of nerves, or neurons, in the body:

1)Autonomic nerves. These nerves control the involuntary or partially voluntary activities of your body, including heart rate, blood pressure, digestion, and temperature regulation.

2)Motor nerves. These nerves control your movements and actions by passing information from your brain and spinal cord to your muscles.

3)Sensory nerves. These nerves relay information from your skin and muscles back to your spinal cord and brain. The information is then processed to let you feel pain and other sensations.

Nerve pain and nerve damage can be mild. But, because nerves are essential to all you do, nerve pain and damage can seriously affect your quality of life.

With nerve damage there can be a wide array of symptoms. Which ones you may have depends on the location and type of nerves that are affected. Damage can occur to nerves in your brain and spinal cord. It can also occur in the peripheral nerves, which are located throughout the rest of your body. Autonomic nerve damage may produce the following symptoms:

1) Inability to sense chest pain, such as angina or heart attack
2) Too much sweating (known as hyperhidrosis) or too little sweating (known as anhidrosis)
3) Lightheadedness
4) Dry eyes and mouth
5) Constipation
6) Bladder dysfunction
7) Sexual dysfunction

Damage to motor nerves may produce the following symptoms:

1) Weakness
2) Muscle atrophy
3) Twitching, also known as fasciculation
4) Taralysis

Sensory nerve damage may produce the following symptoms:

1) Pain
2) Sensitivity
3) Numbness
4) Tingling or prickling
5) Problems with positional awareness

In some instances, people with nerve damage will have symptoms that indicate damage to two, or even three, different types of nerves. For instance, you might experience weakness and burning of your legs at the same time.

What Causes Nerve Pain and Nerve Damage?

There are more than 100 different types of nerve damage. The various types may have different symptoms and may require different types of treatment.

More than 20 million Americans are afflicted with peripheral nerve damage. This type of damage becomes increasingly more common with age. In one out of every three people with peripheral nerve damage, the damage comes from diabetes. In another third, the cause of the nerve damage remains unknown.

While not an exhaustive list, the following are some of the possible causes of nerve pain and nerve damage:

Autoimmune diseases . A variety of different types of autoimmune diseases can produce symptoms of nerve pain and nerve damage. These include: multiple sclerosis, Guillain-Barre syndrome (a rare condition in which the immune system attacks the peripheral nerves), myasthenia gravis, lupus, and inflammatory bowel disease.

Cancer . Cancer can cause nerve pain and nerve damage in multiple ways. In some instances, cancerous masses may push against or crush nerves. In other cases, certain types of cancer may result in nutritional deficiencies that affect nerve function. Additionally, chemotherapy and radiation may produce nerve pain and nerve damage in certain individuals.

Compression/trauma. Anything that results in trauma or compression of nerves can result in nerve pain and nerve damage. This includes pinched nerves in the neck, crush injuries, and carpal tunnel syndrome.

Diabetes. About 50% of people with diabetes suffer from nerve damage, which becomes more likely as the disease progresses. Diabetic neuropathy is a serious complication and may affect all three types of neurons. Sensory nerves are most often affected, causing burning or numbness. If you have diabetes and are experiencing symptoms of nerve pain or nerve damage, you should consult a medical professional as soon as possible.

Drug side effects and toxic substances. Various substances that are taken into the body intentionally or unintentionally have the ability to cause nerve pain and nerve damage. These include medications, such as chemotherapies for cancer and certain drugs used to treat HIV. Toxic substances that may be ingested accidentally, including lead, arsenic, and mercury, may also cause damage to your nerves.

Motor neuron diseases. The motor neurons are nerves in your brain and spinal column that communicate with the muscles throughout your body. Diseases that affect these nerves, including amyotrophic lateral sclerosis, also called ALS or Lou Gehrigs disease, can result in progressively worsening nerve damage.

Nutritional deficiencies. Deficiencies of certain nutrients, including vitamins B6 and B12, may produce symptoms of nerve pain and nerve damage, including weakness or burning sensations. Nutritional deficiencies that cause nerve damage may also result from excessive alcohol ingestion or develop after gastric surgery.

Infectious disease. Certain infectious diseases have the ability to affect the nerves in your body. These conditions include Lyme disease, the herpes viruses, HIV, and hepatitis C.

Adopted from webmd.com