Causes of type 1 diabetes
The exact cause of type 1 diabetes is unknown. What is known is that your immune system — which normally fights harmful bacteria or viruses — attacks and destroys your insulin-producing cells in the pancreas. This leaves you with little or no insulin. Instead of being transported into your cells, sugar builds up in your bloodstream.
Type 1 is thought to be caused by a combination of genetic susceptibility and environmental factors, though exactly what many of those factors are is still unclear.
Causes of prediabetes and type 2 diabetes
In pre-diabetes — which can lead to type 2 diabetes — and in type 2 diabetes, your cells become resistant to the action of insulin, and your pancreas is unable to make enough insulin to overcome this resistance. Instead of moving into your cells where it’s needed for energy, sugar builds up in your bloodstream.
Exactly why this happens is uncertain, although it’s believed that genetic and environmental factors play a role in the development of type 2 diabetes. Being overweight is strongly linked to the development of type 2 diabetes, but not everyone with type 2 is overweight.
Causes of gestational diabetes
During pregnancy, the placenta produces hormones to sustain your pregnancy. These hormones make your cells more resistant to insulin.
Normally, your pancreas responds by producing enough extra insulin to overcome this resistance. But sometimes your pancreas can’t keep up. When this happens, too little glucose gets into your cells and too much stays in your blood, resulting in gestational diabetes.
Other factors that may contribute to diabetic neuropathy include:
- Inflammation in the nerves caused by an autoimmune response. This occurs when your immune system mistakenly attacks part of your body as if it were a foreign organism.
- Genetic factors unrelated to diabetes that make some people more susceptible to nerve damage.
- Smoking and alcohol abuse, which damage both nerves and blood vessels and significantly increase the risk of infections.
Anyone who has diabetes can develop neuropathy, but these factors make you more susceptible to nerve damage:
- Poor blood sugar control. This is the greatest risk factor for every complication of diabetes, including nerve damage. Keeping blood sugar consistently within your target range is the best way to protect the health of your nerves and blood vessels.
- Length of time you have diabetes. Your risk of diabetic neuropathy increases the longer you have diabetes, especially if your blood sugar isn’t well-controlled.
- Kidney disease. Diabetes can cause damage to the kidneys, which may increase the toxins in the blood and contribute to nerve damage.
- Being overweight. Having a body mass index greater than 24 may increase your risk of developing diabetic neuropathy.
- Smoking. Smoking narrows and hardens your arteries, reducing blood flow to your legs and feet. This makes it more difficult for wounds to heal and damages the integrity of the peripheral nerves.