Nerve Disease (Neuropathy)
About 15 million Americans suffer from neuropathy, a nerve problem that can damage the nervous system and cause unrelenting aches and pains. In particular, 60% of diabetics develop peripheral neuropathy when their blood glucose reaches and remains at dangerous levels for several years. When blood glucose levels rise too high and remain too high, the glucose molecule attaches itself to cells permanently and is eventually converted to a poison sugar called sorbitol that destroys nerve cells (nerve death). The signs of nerve damage include tingling, burning, and the loss of feeling (touch) in the feet, which lead to a high incidence of foot infections, foot ulcers, and amputations. If motor or autonomic nerves are damaged, this can lead to the loss of muscle control, bladder control, and bowel control. Eventually, after many years of poor blood glucose control and deterioration of the nervous system, the cells in the brain may also become damaged.

Peripheral Neuropathy
The peripheral nerves that go to the arms, hands, legs, and feet are responsible for relaying information from the central nervous system (brain and spinal cord) to muscles and other organs. Peripheral nerves also relay information back to the spinal cord and brain from the skin, joints, and other organs. High blood glucose levels create trace chemicals that damage the blood vessels that bring oxygen to some nerves and cause oxidative stress to nerve cells, and the degeneration of nerve fibers and the myelin sheath covering on the nerves. In addition, the high glucose and insulin levels can cause calcium and other minerals to leech from the synaptic junctions. Synaptic junctions can only retain a limited amount of glucose, insulin, and electrolytes; therefore, when glucose or excess insulin enters, something else must be released. Since there is usually a plentiful supply of calcium and potassium from food, as well as a plentiful supply of oxygen from the lungs, these elements are generally the first to be discharged. However, once the nerve cell becomes shorter, it remains in that condition until it is over stimulated.

The calcium ion pump is responsible for the propagation of the nerve impulse along the myelin sheath. As a result, each time the synaptic junctions and nerve cells lose calcium, they conduct fewer impulses. A similar process is facilitated by the electric fields of tiny electrical charges, which are keyed to potassium levels. Atrophy occurs when any body part is used with less and less frequency. Similarly, when the electrical signals are not propagating correctly and the body assumes that the nerve is no longer necessary and, to conserve energy, further reduces support for that nerve cell. In turn the nerve cell shrinks in order to function due to a reduced input of fuel and oxygen while still keeping itself viable until the nerve ceases to function.

Consequently untreated diabetes, hypoglycemia or poor glucose control could cause wide variations in the blood calcium, potassium, sugar, insulin, and oxygen levels thereby resulting in oxygen deprivation and loss of nerve integrity. Damaged nerves stop sending messages or send messages too slowly or at the wrong times. This leads to neuropathic symptoms such as tingling or numbness in the feet.

As a result, damage to these peripheral nerves can make the arms, hands, legs, or feet feel numb. Also, you might not be able to feel pain, heat, or cold when you should. You may feel shooting pains, burning or tingling like “pins and needles”. These feelings are often worse at night and make it difficult to sleep. Most of the time these feelings are on both sides of your body, like in both of your feet, but they can be on just one side. Some of the other symptoms of peripheral neuropathy include prickly or burning pains, tightness of the skin, hypersensitivity to touch, impaired coordination, balance problems, difficulty climbing stairs or difficulty getting up from a sitting position, urinary urgency, erectile dysfunction, acid reflux and lightheadedness. The numbness that typically accompanies neuropathy can be particularly problematic because minor injuries may go unnoticed, turning into health problems that are not minor at all.

Peripheral nerve damage can change the shape of your feet because foot muscles get weak and the tendons in the foot get shorter. In some cases, failure of nerves controlling blood vessels, intestinal function, and other organs results in abnormal blood pressure, digestion, and loss of other basic involuntary processes. Peripheral neuropathy may involve damage to a single nerve or nerve group (mononeuropathy) or may affect multiple nerves (polyneuropathy).

Damage to Autonomic Nervous System & Brain

• After a period of years, diabetes can damage the nerves of the autonomic nervous system, and eventually, even affect the nerve cells of the brain. Damage to the autonomic nervous system causes one or more of the following:
• Difficulty in feeling the symptoms of hypoglycemia (low blood sugar).
• Nausea, vomiting, constipation, or diarrhea due to damage to the autonomic nerves that go to the stomach, intestines, and other parts of the digestive system, making food pass through the digestive system too slowly or too quickly.
• Erectile dysfunction or impotence due to the damage to the autonomic nerves going to the man’s penis nerves.
• Prevention of a woman’s vagina from getting wet when she wants to have sex or having less feeling around her vagina.
• A faster beating of the heart or the heart beating at different speeds.
• Difficulty in knowing when to go to the bathroom due to damage to the autonomic nerves that go to the bladder. The damage can also make it hard to feel when your bladder is empty. Both problems can cause you to hold urine for too long, which can lead to bladder infections.
• Slow movement of your blood to keep your blood pressure steady when you change position due to damage to the autonomic nerves going to the blood vessels that keep your blood pressure steady. When you go from lying down to standing up or when you exercise a lot, the sudden changes in blood pressure can make you dizzy.
• Double vision due to damage to the autonomic nerves going to the cranial nerves that control the eye muscles. Damage to these nerves usually happens in one eye. This problem happens all of a sudden and usually lasts for a short time.
• A side of the face hangs lower or sags due to damage to the autonomic nerves going to the cranial nerves that control the sides of the face. Damage to these nerves usually happens on only one side of the face. This nerve damage causes that side of the face to hang lower or sag. Usually the lower eyelid and lips sag. This problem, which is called Bell’s palsy, happens all of a sudden and tends to correct itself most of the time.

Diagnosis & Tests
The diagnosis of diabetic neuropathy is made on the basis of symptoms and a physical exam. During the exam, the doctor may check blood pressure and heart rate, muscle strength, reflexes, and sensitivity to position, vibration, temperature, or a light touch.

The doctor may also perform other tests to help determine the type and extent of nerve damage including a foot exam, nerve conduction test, electromyography test, sensory testing, heart rate variability check, ultrasound, and a nerve or skin biopsy.

A comprehensive foot exam assesses skin, circulation, and sensation. The test can be done during a routine office visit. To assess protective sensation or feeling in the foot, a nylon monofilament (similar to a bristle on a hairbrush) attached to a wand is used to touch the foot. Those who cannot sense pressure from the monofilament have lost protective sensation and are at risk for developing foot sores that may not heal properly. Other tests include checking reflexes and assessing vibration perception, which is more sensitive than touch pressure.

A nerve conduction test checks the transmission of electrical current through a nerve. With this test, an image of the nerve conducting an electrical signal is projected onto a screen. Nerve impulses that seem slower or weaker than usual indicate possible damage. This test allows the doctor to assess the condition of all the nerves in the arms and legs.

An electromyography (EMG) test shows how well muscles respond to electrical signals transmitted by nearby nerves. The electrical activity of the muscle is displayed on a screen. A response that is slower or weaker than usual suggests damage to the nerve or muscle. This test is often done at the same time as nerve conduction tests.

An ultrasound test uses sound waves to produce an image of internal organs. An ultrasound of the bladder and other parts of the urinary tract, for example, can show how these organs preserve a normal structure and whether the bladder empties completely after urination.

Brain Damage
Current research indicates a connection between diabetes and Alzheimer’s disease. Since diabetes damages the nerves of the peripheral and autonomic nervous systems, it would follow that, eventually, it would affect the nerve cells of the brain itself.

The average human brain, which weighs about 3 pounds, is comprised of billions of neurons (brain cells), water, and phospholipids, namely arachidonic acid and docosahexaenoic acid. The brain produces electrical signals, which, together with chemical reactions, lets the parts of the body communicate. Although the brain is only 2% of the body’s weight, it uses 20% of the oxygen supply, more than 50% of the glucose, and gets 20% of the blood flow. Blood vessels (arteries, capillaries, veins) supply the brain with oxygen and nourishment, and take away waste. More subtly, the blood-brain barrier protects the brain from chemical intrusion from the rest of the body. Blood flowing into the brain is filtered so that many harmful chemicals cannot enter the brain.

When a part of the brain (e.g. brain cells, blood vessels, neuro-transmitters) becomes damaged due to a combination of consistently high blood glucose levels and other factors, after a period of years, a diabetic may develop Alzheimer’s or some other brain-related ailment. These other factors may include exposure to aluminum (e.g. sodas, aluminum utensils) and other chemicals and toxins that have gradually built up in the body, and some accumulating in the brain. This can lead to a formation of a sticky plaque that inhibits the transmission of brain signals. This decrease in signal transmission causes atrophy and death of the brain cells, which leads to further decreased signal transmission, and decreased neural transmission, which leads to further deterioration of the brain’s function. This decrease in brain function may be exhibited in many ways, including a significant increase in memory loss, e.g. confusion, forgetfulness, or a major change in behavioral and personality such as unprovoked anger or loss of social skills.

Note: Neurotransmitters are small molecules whose function is to transmit nerve signals (impulses) from one nerve cell to another. Neurotransmitters are chemical messengers that neurons use to tell other neurons that they have received an impulse. There are many different neurotransmitters - some trigger the receiving neuron to send an impulse and some stop it from doing so. Neurotransmitters include: acetylcholine, serotonin, histamine, glutamate, gamma aminobutyric acid glycine, aspartate, histamine, norepinephrine, epinephrine (adrenalin), endorphins, dopamine, adenosine triphosphate (ATP), and nitric oxide.

Because of the amount of time that it may take for the brain to begin deterioration, the diabetic will experience problems with one or more of the other organs long before a disease like Alzheimer’s settles in. Consequently, there is time to nourish, protect, and exercise the brain to prevent these types of complications.